diff --git a/AGENTS.md b/AGENTS.md
index 3989271f4..98e9640e3 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -204,14 +204,14 @@ oh-my-opencode/
 
 | Agent | Model | Purpose |
 |-------|-------|---------|
-| Sisyphus | anthropic/claude-opus-4-5 | Primary orchestrator (fallback: kimi-k2.5 → glm-4.7 → gpt-5.2-codex → gemini-3-pro) |
-| Hephaestus | openai/gpt-5.2-codex | Autonomous deep worker, "The Legitimate Craftsman" (requires gpt-5.2-codex, no fallback) |
+| Sisyphus | anthropic/claude-opus-4-6 | Primary orchestrator (fallback: kimi-k2.5 → glm-4.7 → gpt-5.3-codex → gemini-3-pro) |
+| Hephaestus | openai/gpt-5.3-codex | Autonomous deep worker, "The Legitimate Craftsman" (requires gpt-5.3-codex, no fallback) |
 | Atlas | anthropic/claude-sonnet-4-5 | Master orchestrator (fallback: kimi-k2.5 → gpt-5.2) |
 | oracle | openai/gpt-5.2 | Consultation, debugging |
 | librarian | zai-coding-plan/glm-4.7 | Docs, GitHub search (fallback: glm-4.7-free) |
 | explore | xai/grok-code-fast-1 | Fast codebase grep (fallback: claude-haiku-4-5 → gpt-5-mini → gpt-5-nano) |
 | multimodal-looker | google/gemini-3-flash | PDF/image analysis |
-| Prometheus | anthropic/claude-opus-4-5 | Strategic planning (fallback: kimi-k2.5 → gpt-5.2) |
+| Prometheus | anthropic/claude-opus-4-6 | Strategic planning (fallback: kimi-k2.5 → gpt-5.2) |
 
 ## COMMANDS
 
diff --git a/docs/category-skill-guide.md b/docs/category-skill-guide.md
index 217b05b1e..b3de37a3d 100644
--- a/docs/category-skill-guide.md
+++ b/docs/category-skill-guide.md
@@ -22,12 +22,12 @@ A Category is an agent configuration preset optimized for specific domains.
 | Category | Default Model | Use Cases |
 |----------|---------------|-----------|
 | `visual-engineering` | `google/gemini-3-pro` | Frontend, UI/UX, design, styling, animation |
-| `ultrabrain` | `openai/gpt-5.2-codex` (xhigh) | Deep logical reasoning, complex architecture decisions requiring extensive analysis |
-| `deep` | `openai/gpt-5.2-codex` (medium) | Goal-oriented autonomous problem-solving. Thorough research before action. For hairy problems requiring deep understanding. |
+| `ultrabrain` | `openai/gpt-5.3-codex` (xhigh) | Deep logical reasoning, complex architecture decisions requiring extensive analysis |
+| `deep` | `openai/gpt-5.3-codex` (medium) | Goal-oriented autonomous problem-solving. Thorough research before action. For hairy problems requiring deep understanding. |
 | `artistry` | `google/gemini-3-pro` (max) | Highly creative/artistic tasks, novel ideas |
 | `quick` | `anthropic/claude-haiku-4-5` | Trivial tasks - single file changes, typo fixes, simple modifications |
 | `unspecified-low` | `anthropic/claude-sonnet-4-5` | Tasks that don't fit other categories, low effort required |
-| `unspecified-high` | `anthropic/claude-opus-4-5` (max) | Tasks that don't fit other categories, high effort required |
+| `unspecified-high` | `anthropic/claude-opus-4-6` (max) | Tasks that don't fit other categories, high effort required |
 | `writing` | `google/gemini-3-flash` | Documentation, prose, technical writing |
 
 ### Usage
@@ -159,7 +159,7 @@ You can fine-tune categories in `oh-my-opencode.json`.
 | Field | Type | Description |
 |-------|------|-------------|
 | `description` | string | Human-readable description of the category's purpose. Shown in delegate_task prompt. |
-| `model` | string | AI model ID to use (e.g., `anthropic/claude-opus-4-5`) |
+| `model` | string | AI model ID to use (e.g., `anthropic/claude-opus-4-6`) |
 | `variant` | string | Model variant (e.g., `max`, `xhigh`) |
 | `temperature` | number | Creativity level (0.0 ~ 2.0). Lower is more deterministic. |
 | `top_p` | number | Nucleus sampling parameter (0.0 ~ 1.0) |
@@ -191,7 +191,7 @@ You can fine-tune categories in `oh-my-opencode.json`.
 
     // 3. Configure thinking model and restrict tools
     "deep-reasoning": {
-      "model": "anthropic/claude-opus-4-5",
+      "model": "anthropic/claude-opus-4-6",
       "thinking": {
         "type": "enabled",
         "budgetTokens": 32000
diff --git a/docs/configurations.md b/docs/configurations.md
index 7111f5c8b..648ee75ac 100644
--- a/docs/configurations.md
+++ b/docs/configurations.md
@@ -693,7 +693,7 @@ Configure concurrency limits for background agent tasks. This controls how many
       "google": 10
     },
     "modelConcurrency": {
-      "anthropic/claude-opus-4-5": 2,
+      "anthropic/claude-opus-4-6": 2,
       "google/gemini-3-flash": 10
     }
   }
@@ -705,7 +705,7 @@ Configure concurrency limits for background agent tasks. This controls how many
 | `defaultConcurrency`  | -       | Default maximum concurrent background tasks for all providers/models                                                    |
 | `staleTimeoutMs`      | `180000` | Stale timeout in milliseconds - interrupt tasks with no activity for this duration (minimum: 60000 = 1 minute)             |
 | `providerConcurrency` | -       | Per-provider concurrency limits. Keys are provider names (e.g., `anthropic`, `openai`, `google`)                        |
-| `modelConcurrency`    | -       | Per-model concurrency limits. Keys are full model names (e.g., `anthropic/claude-opus-4-5`). Overrides provider limits. |
+| `modelConcurrency`    | -       | Per-model concurrency limits. Keys are full model names (e.g., `anthropic/claude-opus-4-6`). Overrides provider limits. |
 
 **Priority Order**: `modelConcurrency` > `providerConcurrency` > `defaultConcurrency`
 
@@ -725,11 +725,11 @@ All 7 categories come with optimal model defaults, but **you must configure them
 | Category             | Built-in Default Model             | Description                                                          |
 | -------------------- | ---------------------------------- | -------------------------------------------------------------------- |
 | `visual-engineering` | `google/gemini-3-pro-preview`      | Frontend, UI/UX, design, styling, animation                          |
-| `ultrabrain`         | `openai/gpt-5.2-codex` (xhigh)     | Deep logical reasoning, complex architecture decisions               |
+| `ultrabrain`         | `openai/gpt-5.3-codex` (xhigh)     | Deep logical reasoning, complex architecture decisions               |
 | `artistry`           | `google/gemini-3-pro-preview` (max)| Highly creative/artistic tasks, novel ideas                          |
 | `quick`              | `anthropic/claude-haiku-4-5`       | Trivial tasks - single file changes, typo fixes, simple modifications|
 | `unspecified-low`    | `anthropic/claude-sonnet-4-5`      | Tasks that don't fit other categories, low effort required           |
-| `unspecified-high`   | `anthropic/claude-opus-4-5` (max)  | Tasks that don't fit other categories, high effort required          |
+| `unspecified-high`   | `anthropic/claude-opus-4-6` (max)  | Tasks that don't fit other categories, high effort required          |
 | `writing`            | `google/gemini-3-flash-preview`    | Documentation, prose, technical writing                              |
 
 ### ⚠️ Critical: Model Resolution Priority
@@ -768,7 +768,7 @@ All 7 categories come with optimal model defaults, but **you must configure them
       "model": "google/gemini-3-pro-preview"
     },
     "ultrabrain": { 
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh"
     },
     "artistry": { 
@@ -782,7 +782,7 @@ All 7 categories come with optimal model defaults, but **you must configure them
       "model": "anthropic/claude-sonnet-4-5"
     },
     "unspecified-high": { 
-      "model": "anthropic/claude-opus-4-5",
+      "model": "anthropic/claude-opus-4-6",
       "variant": "max"
     },
     "writing": { 
@@ -870,9 +870,9 @@ At runtime, Oh My OpenCode uses a 3-step resolution process to determine which m
 │   │ anthropic → github-copilot → opencode → antigravity     │   │
 │   │     │            │              │            │          │   │
 │   │     ▼            ▼              ▼            ▼          │   │
-│   │ Try: anthropic/claude-opus-4-5                          │   │
-│   │ Try: github-copilot/claude-opus-4-5                     │   │
-│   │ Try: opencode/claude-opus-4-5                           │   │
+│   │ Try: anthropic/claude-opus-4-6                          │   │
+│   │ Try: github-copilot/claude-opus-4-6                     │   │
+│   │ Try: opencode/claude-opus-4-6                           │   │
 │   │ ...                                                     │   │
 │   │                                                         │   │
 │   │ Found in available models? → Return matched model       │   │
@@ -894,13 +894,13 @@ Each agent has a defined provider priority chain. The system tries providers in
 
 | Agent | Model (no prefix) | Provider Priority Chain |
 |-------|-------------------|-------------------------|
-| **Sisyphus** | `claude-opus-4-5` | anthropic → kimi-for-coding → zai-coding-plan → openai → google |
+| **Sisyphus** | `claude-opus-4-6` | anthropic → kimi-for-coding → zai-coding-plan → openai → google |
 | **oracle** | `gpt-5.2` | openai → google → anthropic |
 | **librarian** | `glm-4.7` | zai-coding-plan → opencode → anthropic |
 | **explore** | `claude-haiku-4-5` | anthropic → github-copilot → opencode |
 | **multimodal-looker** | `gemini-3-flash` | google → openai → zai-coding-plan → kimi-for-coding → anthropic → opencode |
-| **Prometheus (Planner)** | `claude-opus-4-5` | anthropic → kimi-for-coding → openai → google |
-| **Metis (Plan Consultant)** | `claude-opus-4-5` | anthropic → kimi-for-coding → openai → google |
+| **Prometheus (Planner)** | `claude-opus-4-6` | anthropic → kimi-for-coding → openai → google |
+| **Metis (Plan Consultant)** | `claude-opus-4-6` | anthropic → kimi-for-coding → openai → google |
 | **Momus (Plan Reviewer)** | `gpt-5.2` | openai → anthropic → google |
 | **Atlas** | `claude-sonnet-4-5` | anthropic → kimi-for-coding → openai → google |
 
@@ -911,12 +911,12 @@ Categories follow the same resolution logic:
 | Category | Model (no prefix) | Provider Priority Chain |
 |----------|-------------------|-------------------------|
 | **visual-engineering** | `gemini-3-pro` | google → anthropic → zai-coding-plan |
-| **ultrabrain** | `gpt-5.2-codex` | openai → google → anthropic |
-| **deep** | `gpt-5.2-codex` | openai → anthropic → google |
+| **ultrabrain** | `gpt-5.3-codex` | openai → google → anthropic |
+| **deep** | `gpt-5.3-codex` | openai → anthropic → google |
 | **artistry** | `gemini-3-pro` | google → anthropic → openai |
 | **quick** | `claude-haiku-4-5` | anthropic → google → opencode |
 | **unspecified-low** | `claude-sonnet-4-5` | anthropic → openai → google |
-| **unspecified-high** | `claude-opus-4-5` | anthropic → openai → google |
+| **unspecified-high** | `claude-opus-4-6` | anthropic → openai → google |
 | **writing** | `gemini-3-flash` | google → anthropic → zai-coding-plan → openai |
 
 ### Checking Your Configuration
@@ -949,7 +949,7 @@ Override any agent or category model in `oh-my-opencode.json`:
   },
   "categories": {
     "visual-engineering": {
-      "model": "anthropic/claude-opus-4-5"
+      "model": "anthropic/claude-opus-4-6"
     }
   }
 }
diff --git a/docs/features.md b/docs/features.md
index 25284af5b..b750ce7d6 100644
--- a/docs/features.md
+++ b/docs/features.md
@@ -10,8 +10,8 @@ Oh-My-OpenCode provides 11 specialized AI agents. Each has distinct expertise, o
 
 | Agent | Model | Purpose |
 |-------|-------|---------|
-| **Sisyphus** | `anthropic/claude-opus-4-5` | **The default orchestrator.** Plans, delegates, and executes complex tasks using specialized subagents with aggressive parallel execution. Todo-driven workflow with extended thinking (32k budget). Fallback: kimi-k2.5 → glm-4.7 → gpt-5.2-codex → gemini-3-pro. |
-| **Hephaestus** | `openai/gpt-5.2-codex` | **The Legitimate Craftsman.** Autonomous deep worker inspired by AmpCode's deep mode. Goal-oriented execution with thorough research before action. Explores codebase patterns, completes tasks end-to-end without premature stopping. Named after the Greek god of forge and craftsmanship. Requires gpt-5.2-codex (no fallback - only activates when this model is available). |
+| **Sisyphus** | `anthropic/claude-opus-4-6` | **The default orchestrator.** Plans, delegates, and executes complex tasks using specialized subagents with aggressive parallel execution. Todo-driven workflow with extended thinking (32k budget). Fallback: kimi-k2.5 → glm-4.7 → gpt-5.3-codex → gemini-3-pro. |
+| **Hephaestus** | `openai/gpt-5.3-codex` | **The Legitimate Craftsman.** Autonomous deep worker inspired by AmpCode's deep mode. Goal-oriented execution with thorough research before action. Explores codebase patterns, completes tasks end-to-end without premature stopping. Named after the Greek god of forge and craftsmanship. Requires gpt-5.3-codex (no fallback - only activates when this model is available). |
 | **oracle** | `openai/gpt-5.2` | Architecture decisions, code review, debugging. Read-only consultation - stellar logical reasoning and deep analysis. Inspired by AmpCode. |
 | **librarian** | `zai-coding-plan/glm-4.7` | Multi-repo analysis, documentation lookup, OSS implementation examples. Deep codebase understanding with evidence-based answers. Fallback: glm-4.7-free → claude-sonnet-4-5. |
 | **explore** | `anthropic/claude-haiku-4-5` | Fast codebase exploration and contextual grep. Fallback: gpt-5-mini → gpt-5-nano. |
@@ -21,9 +21,9 @@ Oh-My-OpenCode provides 11 specialized AI agents. Each has distinct expertise, o
 
 | Agent | Model | Purpose |
 |-------|-------|---------|
-| **Prometheus** | `anthropic/claude-opus-4-5` | Strategic planner with interview mode. Creates detailed work plans through iterative questioning. Fallback: kimi-k2.5 → gpt-5.2 → gemini-3-pro. |
-| **Metis** | `anthropic/claude-opus-4-5` | Plan consultant - pre-planning analysis. Identifies hidden intentions, ambiguities, and AI failure points. Fallback: kimi-k2.5 → gpt-5.2 → gemini-3-pro. |
-| **Momus** | `openai/gpt-5.2` | Plan reviewer - validates plans against clarity, verifiability, and completeness standards. Fallback: gpt-5.2 → claude-opus-4-5 → gemini-3-pro. |
+| **Prometheus** | `anthropic/claude-opus-4-6` | Strategic planner with interview mode. Creates detailed work plans through iterative questioning. Fallback: kimi-k2.5 → gpt-5.2 → gemini-3-pro. |
+| **Metis** | `anthropic/claude-opus-4-6` | Plan consultant - pre-planning analysis. Identifies hidden intentions, ambiguities, and AI failure points. Fallback: kimi-k2.5 → gpt-5.2 → gemini-3-pro. |
+| **Momus** | `openai/gpt-5.2` | Plan reviewer - validates plans against clarity, verifiability, and completeness standards. Fallback: gpt-5.2 → claude-opus-4-6 → gemini-3-pro. |
 
 ### Invoking Agents
 
diff --git a/docs/guide/installation.md b/docs/guide/installation.md
index 0f6dff32d..bac440348 100644
--- a/docs/guide/installation.md
+++ b/docs/guide/installation.md
@@ -196,7 +196,7 @@ When GitHub Copilot is the best available provider, oh-my-opencode uses these mo
 
 | Agent         | Model                            |
 | ------------- | -------------------------------- |
-| **Sisyphus**  | `github-copilot/claude-opus-4.5` |
+| **Sisyphus**  | `github-copilot/claude-opus-4.6` |
 | **Oracle**    | `github-copilot/gpt-5.2`         |
 | **Explore**   | `opencode/gpt-5-nano`              |
 | **Librarian** | `zai-coding-plan/glm-4.7` (if Z.ai available) or fallback |
@@ -218,13 +218,13 @@ If Z.ai is the only provider available, all agents will use GLM models:
 
 #### OpenCode Zen
 
-OpenCode Zen provides access to `opencode/` prefixed models including `opencode/claude-opus-4-5`, `opencode/gpt-5.2`, `opencode/gpt-5-nano`, and `opencode/glm-4.7-free`.
+OpenCode Zen provides access to `opencode/` prefixed models including `opencode/claude-opus-4-6`, `opencode/gpt-5.2`, `opencode/gpt-5-nano`, and `opencode/glm-4.7-free`.
 
 When OpenCode Zen is the best available provider (no native or Copilot), these models are used:
 
 | Agent         | Model                            |
 | ------------- | -------------------------------- |
-| **Sisyphus**  | `opencode/claude-opus-4-5`       |
+| **Sisyphus**  | `opencode/claude-opus-4-6`       |
 | **Oracle**    | `opencode/gpt-5.2`               |
 | **Explore**   | `opencode/gpt-5-nano`             |
 | **Librarian** | `opencode/glm-4.7-free`          |
diff --git a/docs/guide/understanding-orchestration-system.md b/docs/guide/understanding-orchestration-system.md
index 8af82b444..148de716f 100644
--- a/docs/guide/understanding-orchestration-system.md
+++ b/docs/guide/understanding-orchestration-system.md
@@ -277,7 +277,7 @@ This "boulder pushing" mechanism is why the system is named after Sisyphus.
 ```typescript
 // OLD: Model name creates distributional bias
 delegate_task(agent="gpt-5.2", prompt="...")  // Model knows its limitations
-delegate_task(agent="claude-opus-4.5", prompt="...")  // Different self-perception
+delegate_task(agent="claude-opus-4.6", prompt="...")  // Different self-perception
 ```
 
 **The Solution: Semantic Categories:**
diff --git a/docs/orchestration-guide.md b/docs/orchestration-guide.md
index 08a113ae2..0eac77567 100644
--- a/docs/orchestration-guide.md
+++ b/docs/orchestration-guide.md
@@ -275,7 +275,7 @@ flowchart TD
 
 ### 🔮 Prometheus (The Planner)
 
-- **Model**: `anthropic/claude-opus-4-5`
+- **Model**: `anthropic/claude-opus-4-6`
 - **Role**: Strategic planning, requirements interviews, work plan creation
 - **Constraint**: **READ-ONLY**. Can only create/modify markdown files within `.sisyphus/` directory.
 - **Characteristic**: Never writes code directly, focuses solely on "how to do it".
diff --git a/sisyphus-prompt.md b/sisyphus-prompt.md
index 263e9c040..177a97c8f 100644
--- a/sisyphus-prompt.md
+++ b/sisyphus-prompt.md
@@ -7,7 +7,7 @@
 
 | Field | Value |
 |-------|-------|
-| Model | `anthropic/claude-opus-4-5` |
+| Model | `anthropic/claude-opus-4-6` |
 | Max Tokens | `64000` |
 | Mode | `primary` |
 | Thinking | Budget: 32000 |
diff --git a/src/agents/AGENTS.md b/src/agents/AGENTS.md
index b1c05c4cc..79366d796 100644
--- a/src/agents/AGENTS.md
+++ b/src/agents/AGENTS.md
@@ -33,16 +33,16 @@ agents/
 ## AGENT MODELS
 | Agent | Model | Temp | Purpose |
 |-------|-------|------|---------|
-| Sisyphus | anthropic/claude-opus-4-5 | 0.1 | Primary orchestrator (fallback: kimi-k2.5 → glm-4.7 → gpt-5.2-codex → gemini-3-pro) |
-| Hephaestus | openai/gpt-5.2-codex | 0.1 | Autonomous deep worker, "The Legitimate Craftsman" (requires gpt-5.2-codex, no fallback) |
+| Sisyphus | anthropic/claude-opus-4-6 | 0.1 | Primary orchestrator (fallback: kimi-k2.5 → glm-4.7 → gpt-5.3-codex → gemini-3-pro) |
+| Hephaestus | openai/gpt-5.3-codex | 0.1 | Autonomous deep worker, "The Legitimate Craftsman" (requires gpt-5.3-codex, no fallback) |
 | Atlas | anthropic/claude-sonnet-4-5 | 0.1 | Master orchestrator (fallback: kimi-k2.5 → gpt-5.2) |
 | oracle | openai/gpt-5.2 | 0.1 | Consultation, debugging |
 | librarian | zai-coding-plan/glm-4.7 | 0.1 | Docs, GitHub search (fallback: glm-4.7-free) |
 | explore | xai/grok-code-fast-1 | 0.1 | Fast contextual grep (fallback: claude-haiku-4-5 → gpt-5-mini → gpt-5-nano) |
 | multimodal-looker | google/gemini-3-flash | 0.1 | PDF/image analysis |
-| Prometheus | anthropic/claude-opus-4-5 | 0.1 | Strategic planning (fallback: kimi-k2.5 → gpt-5.2) |
-| Metis | anthropic/claude-opus-4-5 | 0.3 | Pre-planning analysis (fallback: kimi-k2.5 → gpt-5.2) |
-| Momus | openai/gpt-5.2 | 0.1 | Plan validation (fallback: claude-opus-4-5) |
+| Prometheus | anthropic/claude-opus-4-6 | 0.1 | Strategic planning (fallback: kimi-k2.5 → gpt-5.2) |
+| Metis | anthropic/claude-opus-4-6 | 0.3 | Pre-planning analysis (fallback: kimi-k2.5 → gpt-5.2) |
+| Momus | openai/gpt-5.2 | 0.1 | Plan validation (fallback: claude-opus-4-6) |
 | Sisyphus-Junior | anthropic/claude-sonnet-4-5 | 0.1 | Category-spawned executor |
 
 ## HOW TO ADD
diff --git a/src/agents/utils.test.ts b/src/agents/utils.test.ts
index 1da865cf7..8c0bda46e 100644
--- a/src/agents/utils.test.ts
+++ b/src/agents/utils.test.ts
@@ -6,14 +6,14 @@ import * as connectedProvidersCache from "../shared/connected-providers-cache"
 import * as modelAvailability from "../shared/model-availability"
 import * as shared from "../shared"
 
-const TEST_DEFAULT_MODEL = "anthropic/claude-opus-4-5"
+const TEST_DEFAULT_MODEL = "anthropic/claude-opus-4-6"
 
 describe("createBuiltinAgents with model overrides", () => {
   test("Sisyphus with default model has thinking config when all models available", async () => {
     // #given
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
       new Set([
-        "anthropic/claude-opus-4-5",
+        "anthropic/claude-opus-4-6",
         "kimi-for-coding/k2p5",
         "opencode/kimi-k2.5-free",
         "zai-coding-plan/glm-4.7",
@@ -26,7 +26,7 @@ describe("createBuiltinAgents with model overrides", () => {
       const agents = await createBuiltinAgents([], {}, undefined, TEST_DEFAULT_MODEL, undefined, undefined, [], {})
 
       // #then
-      expect(agents.sisyphus.model).toBe("anthropic/claude-opus-4-5")
+      expect(agents.sisyphus.model).toBe("anthropic/claude-opus-4-6")
       expect(agents.sisyphus.thinking).toEqual({ type: "enabled", budgetTokens: 32000 })
       expect(agents.sisyphus.reasoningEffort).toBeUndefined()
     } finally {
@@ -81,7 +81,7 @@ describe("createBuiltinAgents with model overrides", () => {
 
   test("Sisyphus is created on first run when no availableModels or cache exist", async () => {
     // #given
-    const systemDefaultModel = "anthropic/claude-opus-4-5"
+    const systemDefaultModel = "anthropic/claude-opus-4-6"
     const cacheSpy = spyOn(connectedProvidersCache, "readConnectedProvidersCache").mockReturnValue(null)
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(new Set())
 
@@ -218,7 +218,7 @@ describe("createBuiltinAgents without systemDefaultModel", () => {
     ])
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
       new Set([
-        "anthropic/claude-opus-4-5",
+        "anthropic/claude-opus-4-6",
         "kimi-for-coding/k2p5",
         "opencode/kimi-k2.5-free",
         "zai-coding-plan/glm-4.7",
@@ -232,7 +232,7 @@ describe("createBuiltinAgents without systemDefaultModel", () => {
 
       // #then
       expect(agents.sisyphus).toBeDefined()
-      expect(agents.sisyphus.model).toBe("anthropic/claude-opus-4-5")
+      expect(agents.sisyphus.model).toBe("anthropic/claude-opus-4-6")
     } finally {
       cacheSpy.mockRestore()
       fetchSpy.mockRestore()
@@ -244,7 +244,7 @@ describe("createBuiltinAgents with requiresProvider gating (hephaestus)", () =>
   test("hephaestus is not created when no required provider is connected", async () => {
     // #given - only anthropic models available, not in hephaestus requiresProvider
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
-      new Set(["anthropic/claude-opus-4-5"])
+      new Set(["anthropic/claude-opus-4-6"])
     )
     const cacheSpy = spyOn(connectedProvidersCache, "readConnectedProvidersCache").mockReturnValue(["anthropic"])
 
@@ -263,7 +263,7 @@ describe("createBuiltinAgents with requiresProvider gating (hephaestus)", () =>
   test("hephaestus is created when openai provider is connected", async () => {
     // #given - openai provider has models available
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
-      new Set(["openai/gpt-5.2-codex"])
+      new Set(["openai/gpt-5.3-codex"])
     )
 
     try {
@@ -280,7 +280,7 @@ describe("createBuiltinAgents with requiresProvider gating (hephaestus)", () =>
   test("hephaestus is created when github-copilot provider is connected", async () => {
     // #given - github-copilot provider has models available
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
-      new Set(["github-copilot/gpt-5.2-codex"])
+      new Set(["github-copilot/gpt-5.3-codex"])
     )
 
     try {
@@ -297,7 +297,7 @@ describe("createBuiltinAgents with requiresProvider gating (hephaestus)", () =>
   test("hephaestus is created when opencode provider is connected", async () => {
     // #given - opencode provider has models available
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
-      new Set(["opencode/gpt-5.2-codex"])
+      new Set(["opencode/gpt-5.3-codex"])
     )
 
     try {
@@ -322,7 +322,7 @@ describe("createBuiltinAgents with requiresProvider gating (hephaestus)", () =>
 
       // #then
       expect(agents.hephaestus).toBeDefined()
-      expect(agents.hephaestus.model).toBe("openai/gpt-5.2-codex")
+      expect(agents.hephaestus.model).toBe("openai/gpt-5.3-codex")
     } finally {
       cacheSpy.mockRestore()
       fetchSpy.mockRestore()
@@ -332,10 +332,10 @@ describe("createBuiltinAgents with requiresProvider gating (hephaestus)", () =>
   test("hephaestus is created when explicit config provided even if provider unavailable", async () => {
     // #given
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
-      new Set(["anthropic/claude-opus-4-5"])
+      new Set(["anthropic/claude-opus-4-6"])
     )
     const overrides = {
-      hephaestus: { model: "anthropic/claude-opus-4-5" },
+      hephaestus: { model: "anthropic/claude-opus-4-6" },
     }
 
     try {
@@ -354,7 +354,7 @@ describe("createBuiltinAgents with requiresAnyModel gating (sisyphus)", () => {
   test("sisyphus is created when at least one fallback model is available", async () => {
     // #given
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(
-      new Set(["anthropic/claude-opus-4-5"])
+      new Set(["anthropic/claude-opus-4-6"])
     )
 
     try {
@@ -390,7 +390,7 @@ describe("createBuiltinAgents with requiresAnyModel gating (sisyphus)", () => {
     // #given
     const fetchSpy = spyOn(shared, "fetchAvailableModels").mockResolvedValue(new Set())
     const overrides = {
-      sisyphus: { model: "anthropic/claude-opus-4-5" },
+      sisyphus: { model: "anthropic/claude-opus-4-6" },
     }
 
     try {
@@ -426,7 +426,7 @@ describe("createBuiltinAgents with requiresAnyModel gating (sisyphus)", () => {
 
 describe("buildAgent with category and skills", () => {
   const { buildAgent } = require("./utils")
-  const TEST_MODEL = "anthropic/claude-opus-4-5"
+  const TEST_MODEL = "anthropic/claude-opus-4-6"
 
   beforeEach(() => {
     clearSkillCache()
@@ -572,7 +572,7 @@ describe("buildAgent with category and skills", () => {
     const agent = buildAgent(source["test-agent"], TEST_MODEL)
 
     // #then - category's built-in model and skills are applied
-    expect(agent.model).toBe("openai/gpt-5.2-codex")
+    expect(agent.model).toBe("openai/gpt-5.3-codex")
     expect(agent.variant).toBe("xhigh")
     expect(agent.prompt).toContain("Role: Designer-Turned-Developer")
     expect(agent.prompt).toContain("Task description")
@@ -685,9 +685,9 @@ describe("override.category expansion in createBuiltinAgents", () => {
     // #when
     const agents = await createBuiltinAgents([], overrides, undefined, TEST_DEFAULT_MODEL)
 
-    // #then - ultrabrain category: model=openai/gpt-5.2-codex, variant=xhigh
+    // #then - ultrabrain category: model=openai/gpt-5.3-codex, variant=xhigh
     expect(agents.oracle).toBeDefined()
-    expect(agents.oracle.model).toBe("openai/gpt-5.2-codex")
+    expect(agents.oracle.model).toBe("openai/gpt-5.3-codex")
     expect(agents.oracle.variant).toBe("xhigh")
   })
 
@@ -754,9 +754,9 @@ describe("override.category expansion in createBuiltinAgents", () => {
     // #when
     const agents = await createBuiltinAgents([], overrides, undefined, TEST_DEFAULT_MODEL)
 
-    // #then - ultrabrain category: model=openai/gpt-5.2-codex, variant=xhigh
+    // #then - ultrabrain category: model=openai/gpt-5.3-codex, variant=xhigh
     expect(agents.sisyphus).toBeDefined()
-    expect(agents.sisyphus.model).toBe("openai/gpt-5.2-codex")
+    expect(agents.sisyphus.model).toBe("openai/gpt-5.3-codex")
     expect(agents.sisyphus.variant).toBe("xhigh")
   })
 
@@ -769,9 +769,9 @@ describe("override.category expansion in createBuiltinAgents", () => {
     // #when
     const agents = await createBuiltinAgents([], overrides, undefined, TEST_DEFAULT_MODEL)
 
-    // #then - ultrabrain category: model=openai/gpt-5.2-codex, variant=xhigh
+    // #then - ultrabrain category: model=openai/gpt-5.3-codex, variant=xhigh
     expect(agents.atlas).toBeDefined()
-    expect(agents.atlas.model).toBe("openai/gpt-5.2-codex")
+    expect(agents.atlas.model).toBe("openai/gpt-5.3-codex")
     expect(agents.atlas.variant).toBe("xhigh")
   })
 
diff --git a/src/cli/__snapshots__/model-fallback.test.ts.snap b/src/cli/__snapshots__/model-fallback.test.ts.snap
index 285f14f51..86193b65f 100644
--- a/src/cli/__snapshots__/model-fallback.test.ts.snap
+++ b/src/cli/__snapshots__/model-fallback.test.ts.snap
@@ -197,7 +197,7 @@ exports[`generateModelConfig single native provider uses OpenAI models when only
       "model": "opencode/gpt-5-nano",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -225,22 +225,22 @@ exports[`generateModelConfig single native provider uses OpenAI models when only
   },
   "categories": {
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "opencode/glm-4.7-free",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "unspecified-low": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "visual-engineering": {
@@ -264,7 +264,7 @@ exports[`generateModelConfig single native provider uses OpenAI models with isMa
       "model": "opencode/gpt-5-nano",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -292,14 +292,14 @@ exports[`generateModelConfig single native provider uses OpenAI models with isMa
   },
   "categories": {
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "opencode/glm-4.7-free",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -307,7 +307,7 @@ exports[`generateModelConfig single native provider uses OpenAI models with isMa
       "variant": "high",
     },
     "unspecified-low": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "visual-engineering": {
@@ -451,7 +451,7 @@ exports[`generateModelConfig all native providers uses preferred models from fal
       "model": "anthropic/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -487,14 +487,14 @@ exports[`generateModelConfig all native providers uses preferred models from fal
       "variant": "high",
     },
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "anthropic/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -524,7 +524,7 @@ exports[`generateModelConfig all native providers uses preferred models with isM
       "model": "anthropic/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -560,14 +560,14 @@ exports[`generateModelConfig all native providers uses preferred models with isM
       "variant": "high",
     },
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "anthropic/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -598,14 +598,14 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models when on
       "model": "opencode/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
       "model": "opencode/glm-4.7-free",
     },
     "metis": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
     "momus": {
@@ -620,11 +620,11 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models when on
       "variant": "high",
     },
     "prometheus": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
     "sisyphus": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
   },
@@ -634,14 +634,14 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models when on
       "variant": "high",
     },
     "deep": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "opencode/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -671,14 +671,14 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models with is
       "model": "opencode/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
       "model": "opencode/glm-4.7-free",
     },
     "metis": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
     "momus": {
@@ -693,11 +693,11 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models with is
       "variant": "high",
     },
     "prometheus": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
     "sisyphus": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
   },
@@ -707,18 +707,18 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models with is
       "variant": "high",
     },
     "deep": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "opencode/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
-      "model": "opencode/claude-opus-4-5",
+      "model": "opencode/claude-opus-4-6",
       "variant": "max",
     },
     "unspecified-low": {
@@ -745,14 +745,14 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models when
       "model": "github-copilot/gpt-5-mini",
     },
     "hephaestus": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
       "model": "github-copilot/claude-sonnet-4.5",
     },
     "metis": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "momus": {
@@ -767,11 +767,11 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models when
       "variant": "high",
     },
     "prometheus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "sisyphus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
   },
@@ -781,14 +781,14 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models when
       "variant": "high",
     },
     "deep": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "github-copilot/claude-haiku-4.5",
     },
     "ultrabrain": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -818,14 +818,14 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models with
       "model": "github-copilot/gpt-5-mini",
     },
     "hephaestus": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
       "model": "github-copilot/claude-sonnet-4.5",
     },
     "metis": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "momus": {
@@ -840,11 +840,11 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models with
       "variant": "high",
     },
     "prometheus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "sisyphus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
   },
@@ -854,18 +854,18 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models with
       "variant": "high",
     },
     "deep": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "github-copilot/claude-haiku-4.5",
     },
     "ultrabrain": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "unspecified-low": {
@@ -1002,7 +1002,7 @@ exports[`generateModelConfig mixed provider scenarios uses Claude + OpenCode Zen
       "model": "anthropic/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -1038,14 +1038,14 @@ exports[`generateModelConfig mixed provider scenarios uses Claude + OpenCode Zen
       "variant": "high",
     },
     "deep": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "anthropic/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "opencode/gpt-5.2-codex",
+      "model": "opencode/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -1075,14 +1075,14 @@ exports[`generateModelConfig mixed provider scenarios uses OpenAI + Copilot comb
       "model": "github-copilot/gpt-5-mini",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
       "model": "github-copilot/claude-sonnet-4.5",
     },
     "metis": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "momus": {
@@ -1097,11 +1097,11 @@ exports[`generateModelConfig mixed provider scenarios uses OpenAI + Copilot comb
       "variant": "high",
     },
     "prometheus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "sisyphus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
   },
@@ -1111,14 +1111,14 @@ exports[`generateModelConfig mixed provider scenarios uses OpenAI + Copilot comb
       "variant": "high",
     },
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "github-copilot/claude-haiku-4.5",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -1275,14 +1275,14 @@ exports[`generateModelConfig mixed provider scenarios uses all fallback provider
       "model": "opencode/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
       "model": "zai-coding-plan/glm-4.7",
     },
     "metis": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "momus": {
@@ -1297,11 +1297,11 @@ exports[`generateModelConfig mixed provider scenarios uses all fallback provider
       "variant": "high",
     },
     "prometheus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
     "sisyphus": {
-      "model": "github-copilot/claude-opus-4.5",
+      "model": "github-copilot/claude-opus-4.6",
       "variant": "max",
     },
   },
@@ -1311,14 +1311,14 @@ exports[`generateModelConfig mixed provider scenarios uses all fallback provider
       "variant": "high",
     },
     "deep": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "github-copilot/claude-haiku-4.5",
     },
     "ultrabrain": {
-      "model": "github-copilot/gpt-5.2-codex",
+      "model": "github-copilot/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -1348,7 +1348,7 @@ exports[`generateModelConfig mixed provider scenarios uses all providers togethe
       "model": "anthropic/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -1384,14 +1384,14 @@ exports[`generateModelConfig mixed provider scenarios uses all providers togethe
       "variant": "high",
     },
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "anthropic/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
@@ -1421,7 +1421,7 @@ exports[`generateModelConfig mixed provider scenarios uses all providers with is
       "model": "anthropic/claude-haiku-4-5",
     },
     "hephaestus": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "librarian": {
@@ -1457,14 +1457,14 @@ exports[`generateModelConfig mixed provider scenarios uses all providers with is
       "variant": "high",
     },
     "deep": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "medium",
     },
     "quick": {
       "model": "anthropic/claude-haiku-4-5",
     },
     "ultrabrain": {
-      "model": "openai/gpt-5.2-codex",
+      "model": "openai/gpt-5.3-codex",
       "variant": "xhigh",
     },
     "unspecified-high": {
diff --git a/src/cli/config-manager.test.ts b/src/cli/config-manager.test.ts
index 576206d30..3f98468ce 100644
--- a/src/cli/config-manager.test.ts
+++ b/src/cli/config-manager.test.ts
@@ -298,8 +298,8 @@ describe("generateOmoConfig - model fallback system", () => {
     // #when generating config
     const result = generateOmoConfig(config)
 
-    // #then Sisyphus uses Copilot (OR logic - copilot is in claude-opus-4-5 providers)
-    expect((result.agents as Record<string, { model: string }>).sisyphus.model).toBe("github-copilot/claude-opus-4.5")
+    // #then Sisyphus uses Copilot (OR logic - copilot is in claude-opus-4-6 providers)
+    expect((result.agents as Record<string, { model: string }>).sisyphus.model).toBe("github-copilot/claude-opus-4.6")
   })
 
   test("uses ultimate fallback when no providers configured", () => {
diff --git a/src/cli/doctor/checks/model-resolution.test.ts b/src/cli/doctor/checks/model-resolution.test.ts
index 372990f9e..781564d5e 100644
--- a/src/cli/doctor/checks/model-resolution.test.ts
+++ b/src/cli/doctor/checks/model-resolution.test.ts
@@ -42,7 +42,7 @@ describe("model-resolution check", () => {
       // given: User has override for oracle agent
       const mockConfig = {
         agents: {
-          oracle: { model: "anthropic/claude-opus-4-5" },
+          oracle: { model: "anthropic/claude-opus-4-6" },
         },
       }
 
@@ -51,8 +51,8 @@ describe("model-resolution check", () => {
       // then: Oracle should show the override
       const oracle = info.agents.find((a) => a.name === "oracle")
       expect(oracle).toBeDefined()
-      expect(oracle!.userOverride).toBe("anthropic/claude-opus-4-5")
-      expect(oracle!.effectiveResolution).toBe("User override: anthropic/claude-opus-4-5")
+      expect(oracle!.userOverride).toBe("anthropic/claude-opus-4-6")
+      expect(oracle!.effectiveResolution).toBe("User override: anthropic/claude-opus-4-6")
     })
 
     it("shows user override for category when configured", async () => {
diff --git a/src/cli/index.ts b/src/cli/index.ts
index 5a516fc59..a66a45fcb 100644
--- a/src/cli/index.ts
+++ b/src/cli/index.ts
@@ -43,7 +43,7 @@ Model Providers (Priority: Native > Copilot > OpenCode Zen > Z.ai > Kimi):
   OpenAI        Native openai/ models (GPT-5.2 for Oracle)
   Gemini        Native google/ models (Gemini 3 Pro, Flash)
   Copilot       github-copilot/ models (fallback)
-  OpenCode Zen  opencode/ models (opencode/claude-opus-4-5, etc.)
+  OpenCode Zen  opencode/ models (opencode/claude-opus-4-6, etc.)
   Z.ai          zai-coding-plan/glm-4.7 (Librarian priority)
   Kimi          kimi-for-coding/k2p5 (Sisyphus/Prometheus fallback)
 `)
diff --git a/src/cli/install.ts b/src/cli/install.ts
index c5c4a33be..a4143cd39 100644
--- a/src/cli/install.ts
+++ b/src/cli/install.ts
@@ -243,7 +243,7 @@ async function runTuiMode(detected: DetectedConfig): Promise<InstallConfig | nul
     message: "Do you have access to OpenCode Zen (opencode/ models)?",
     options: [
       { value: "no" as const, label: "No", hint: "Will use other configured providers" },
-      { value: "yes" as const, label: "Yes", hint: "opencode/claude-opus-4-5, opencode/gpt-5.2, etc." },
+      { value: "yes" as const, label: "Yes", hint: "opencode/claude-opus-4-6, opencode/gpt-5.2, etc." },
     ],
     initialValue: initial.opencodeZen,
   })
diff --git a/src/cli/model-fallback.test.ts b/src/cli/model-fallback.test.ts
index 5f266d169..4ac8c0189 100644
--- a/src/cli/model-fallback.test.ts
+++ b/src/cli/model-fallback.test.ts
@@ -417,7 +417,7 @@ describe("generateModelConfig", () => {
       const result = generateModelConfig(config)
 
       // #then
-      expect(result.agents?.hephaestus?.model).toBe("openai/gpt-5.2-codex")
+      expect(result.agents?.hephaestus?.model).toBe("openai/gpt-5.3-codex")
       expect(result.agents?.hephaestus?.variant).toBe("medium")
     })
 
@@ -429,7 +429,7 @@ describe("generateModelConfig", () => {
       const result = generateModelConfig(config)
 
       // #then
-      expect(result.agents?.hephaestus?.model).toBe("github-copilot/gpt-5.2-codex")
+      expect(result.agents?.hephaestus?.model).toBe("github-copilot/gpt-5.3-codex")
       expect(result.agents?.hephaestus?.variant).toBe("medium")
     })
 
@@ -441,7 +441,7 @@ describe("generateModelConfig", () => {
       const result = generateModelConfig(config)
 
       // #then
-      expect(result.agents?.hephaestus?.model).toBe("opencode/gpt-5.2-codex")
+      expect(result.agents?.hephaestus?.model).toBe("opencode/gpt-5.3-codex")
       expect(result.agents?.hephaestus?.variant).toBe("medium")
     })
 
diff --git a/src/cli/model-fallback.ts b/src/cli/model-fallback.ts
index 6d12b24ca..531b8ee40 100644
--- a/src/cli/model-fallback.ts
+++ b/src/cli/model-fallback.ts
@@ -71,7 +71,7 @@ function isProviderAvailable(provider: string, avail: ProviderAvailability): boo
 function transformModelForProvider(provider: string, model: string): string {
   if (provider === "github-copilot") {
     return model
-      .replace("claude-opus-4-5", "claude-opus-4.5")
+      .replace("claude-opus-4-6", "claude-opus-4.6")
       .replace("claude-sonnet-4-5", "claude-sonnet-4.5")
       .replace("claude-haiku-4-5", "claude-haiku-4.5")
       .replace("claude-sonnet-4", "claude-sonnet-4")
diff --git a/src/features/background-agent/concurrency.test.ts b/src/features/background-agent/concurrency.test.ts
index 9482ce8f3..2694e9a70 100644
--- a/src/features/background-agent/concurrency.test.ts
+++ b/src/features/background-agent/concurrency.test.ts
@@ -94,7 +94,7 @@ describe("ConcurrencyManager.getConcurrencyLimit", () => {
 
     // when
     const modelLimit = manager.getConcurrencyLimit("anthropic/claude-sonnet-4-5")
-    const providerLimit = manager.getConcurrencyLimit("anthropic/claude-opus-4-5")
+    const providerLimit = manager.getConcurrencyLimit("anthropic/claude-opus-4-6")
     const defaultLimit = manager.getConcurrencyLimit("google/gemini-3-pro")
 
     // then
diff --git a/src/features/background-agent/manager.test.ts b/src/features/background-agent/manager.test.ts
index cef1ef935..69dde4ddd 100644
--- a/src/features/background-agent/manager.test.ts
+++ b/src/features/background-agent/manager.test.ts
@@ -783,7 +783,7 @@ describe("BackgroundManager.notifyParentSession - dynamic message lookup", () =>
     }
     const currentMessage: CurrentMessage = {
       agent: "sisyphus",
-      model: { providerID: "anthropic", modelID: "claude-opus-4-5" },
+      model: { providerID: "anthropic", modelID: "claude-opus-4-6" },
     }
 
     // when
@@ -791,7 +791,7 @@ describe("BackgroundManager.notifyParentSession - dynamic message lookup", () =>
 
     // then - uses currentMessage values, not task.parentModel/parentAgent
     expect(promptBody.agent).toBe("sisyphus")
-    expect(promptBody.model).toEqual({ providerID: "anthropic", modelID: "claude-opus-4-5" })
+    expect(promptBody.model).toEqual({ providerID: "anthropic", modelID: "claude-opus-4-6" })
   })
 
   test("should fallback to parentAgent when currentMessage.agent is undefined", async () => {
@@ -997,7 +997,7 @@ describe("BackgroundManager.tryCompleteTask", () => {
 
   test("should release concurrency and clear key on completion", async () => {
     // given
-    const concurrencyKey = "anthropic/claude-opus-4-5"
+    const concurrencyKey = "anthropic/claude-opus-4-6"
     const concurrencyManager = getConcurrencyManager(manager)
     await concurrencyManager.acquire(concurrencyKey)
 
@@ -1026,7 +1026,7 @@ describe("BackgroundManager.tryCompleteTask", () => {
 
   test("should prevent double completion and double release", async () => {
     // given
-    const concurrencyKey = "anthropic/claude-opus-4-5"
+    const concurrencyKey = "anthropic/claude-opus-4-6"
     const concurrencyManager = getConcurrencyManager(manager)
     await concurrencyManager.acquire(concurrencyKey)
 
@@ -1657,7 +1657,7 @@ describe("BackgroundManager - Non-blocking Queue Integration", () => {
         description: "Task 1",
         prompt: "Do something",
         agent: "test-agent",
-        model: { providerID: "anthropic", modelID: "claude-opus-4-5" },
+        model: { providerID: "anthropic", modelID: "claude-opus-4-6" },
         parentSessionID: "parent-session",
         parentMessageID: "parent-message",
       }
diff --git a/src/features/task-toast-manager/manager.test.ts b/src/features/task-toast-manager/manager.test.ts
index 090ec8b62..f6a24111a 100644
--- a/src/features/task-toast-manager/manager.test.ts
+++ b/src/features/task-toast-manager/manager.test.ts
@@ -192,7 +192,7 @@ describe("TaskToastManager", () => {
         description: "Task with inherited model",
         agent: "sisyphus-junior",
         isBackground: false,
-        modelInfo: { model: "cliproxy/claude-opus-4-5", type: "inherited" as const },
+        modelInfo: { model: "cliproxy/claude-opus-4-6", type: "inherited" as const },
       }
 
       // when - addTask is called
@@ -202,7 +202,7 @@ describe("TaskToastManager", () => {
       expect(mockClient.tui.showToast).toHaveBeenCalled()
       const call = mockClient.tui.showToast.mock.calls[0][0]
       expect(call.body.message).toContain("[FALLBACK]")
-      expect(call.body.message).toContain("cliproxy/claude-opus-4-5")
+      expect(call.body.message).toContain("cliproxy/claude-opus-4-6")
       expect(call.body.message).toContain("(inherited from parent)")
     })
 
diff --git a/src/hooks/anthropic-context-window-limit-recovery/executor.test.ts b/src/hooks/anthropic-context-window-limit-recovery/executor.test.ts
index ed7e36e22..ca6d383c8 100644
--- a/src/hooks/anthropic-context-window-limit-recovery/executor.test.ts
+++ b/src/hooks/anthropic-context-window-limit-recovery/executor.test.ts
@@ -80,7 +80,7 @@ describe("executeCompact lock management", () => {
   let fakeTimeouts: FakeTimeouts
   const sessionID = "test-session-123"
   const directory = "/test/dir"
-  const msg = { providerID: "anthropic", modelID: "claude-opus-4-5" }
+  const msg = { providerID: "anthropic", modelID: "claude-opus-4-6" }
 
   beforeEach(() => {
     // given: Fresh state for each test
@@ -332,7 +332,7 @@ describe("executeCompact lock management", () => {
     expect(mockClient.session.summarize).toHaveBeenCalledWith(
       expect.objectContaining({
         path: { id: sessionID },
-        body: { providerID: "anthropic", modelID: "claude-opus-4-5", auto: true },
+        body: { providerID: "anthropic", modelID: "claude-opus-4-6", auto: true },
       }),
     )
 
diff --git a/src/hooks/atlas/index.test.ts b/src/hooks/atlas/index.test.ts
index a1b165e7c..b7d5e4207 100644
--- a/src/hooks/atlas/index.test.ts
+++ b/src/hooks/atlas/index.test.ts
@@ -47,7 +47,7 @@ describe("atlas hook", () => {
     }
     const messageData = {
       agent,
-      model: { providerID: "anthropic", modelID: "claude-opus-4-5" },
+      model: { providerID: "anthropic", modelID: "claude-opus-4-6" },
     }
     writeFileSync(join(messageDir, "msg_test001.json"), JSON.stringify(messageData))
   }
diff --git a/src/hooks/preemptive-compaction.test.ts b/src/hooks/preemptive-compaction.test.ts
index b48cccb69..cb027ac7f 100644
--- a/src/hooks/preemptive-compaction.test.ts
+++ b/src/hooks/preemptive-compaction.test.ts
@@ -34,7 +34,7 @@ describe("preemptive-compaction", () => {
             info: {
               role: "assistant",
               providerID: "anthropic",
-              modelID: "claude-opus-4-5",
+              modelID: "claude-opus-4-6",
               tokens: {
                 input: 180000,
                 output: 0,
@@ -69,7 +69,7 @@ describe("preemptive-compaction", () => {
             info: {
               role: "assistant",
               providerID: "anthropic",
-              modelID: "claude-opus-4-5",
+              modelID: "claude-opus-4-6",
               tokens: {
                 input: 100000,
                 output: 0,
diff --git a/src/hooks/think-mode/index.test.ts b/src/hooks/think-mode/index.test.ts
index b039ed31c..29e9a36a9 100644
--- a/src/hooks/think-mode/index.test.ts
+++ b/src/hooks/think-mode/index.test.ts
@@ -41,7 +41,7 @@ describe("createThinkModeHook integration", () => {
         const hook = createThinkModeHook()
         const input = createMockInput(
           "github-copilot",
-          "claude-opus-4-5",
+          "claude-opus-4-6",
           "Please think deeply about this problem"
         )
 
@@ -50,7 +50,7 @@ describe("createThinkModeHook integration", () => {
 
         // then should upgrade to high variant and inject thinking config
         const message = input.message as MessageWithInjectedProps
-        expect(input.message.model?.modelID).toBe("claude-opus-4-5-high")
+        expect(input.message.model?.modelID).toBe("claude-opus-4-6-high")
         expect(message.thinking).toBeDefined()
         expect((message.thinking as Record<string, unknown>)?.type).toBe(
           "enabled"
@@ -61,11 +61,11 @@ describe("createThinkModeHook integration", () => {
       })
 
       it("should handle github-copilot Claude with dots in version", async () => {
-        // given a github-copilot Claude model with dot format (claude-opus-4.5)
+        // given a github-copilot Claude model with dot format (claude-opus-4.6)
         const hook = createThinkModeHook()
         const input = createMockInput(
           "github-copilot",
-          "claude-opus-4.5",
+          "claude-opus-4.6",
           "ultrathink mode"
         )
 
@@ -74,7 +74,7 @@ describe("createThinkModeHook integration", () => {
 
         // then should upgrade to high variant (hyphen format)
         const message = input.message as MessageWithInjectedProps
-        expect(input.message.model?.modelID).toBe("claude-opus-4-5-high")
+        expect(input.message.model?.modelID).toBe("claude-opus-4-6-high")
         expect(message.thinking).toBeDefined()
       })
 
@@ -179,7 +179,7 @@ describe("createThinkModeHook integration", () => {
         const hook = createThinkModeHook()
         const input = createMockInput(
           "github-copilot",
-          "claude-opus-4-5",
+          "claude-opus-4-6",
           "Just do this task"
         )
         const originalModelID = input.message.model?.modelID
@@ -271,7 +271,7 @@ describe("createThinkModeHook integration", () => {
       const hook = createThinkModeHook()
       const input = createMockInput(
         "github-copilot",
-        "claude-opus-4-5-high",
+        "claude-opus-4-6-high",
         "think deeply"
       )
 
@@ -280,7 +280,7 @@ describe("createThinkModeHook integration", () => {
 
       // then should NOT modify the model (already high)
       const message = input.message as MessageWithInjectedProps
-      expect(input.message.model?.modelID).toBe("claude-opus-4-5-high")
+      expect(input.message.model?.modelID).toBe("claude-opus-4-6-high")
       // No additional thinking config should be injected
       expect(message.thinking).toBeUndefined()
     })
@@ -341,13 +341,13 @@ describe("createThinkModeHook integration", () => {
     it("should handle empty prompt gracefully", async () => {
       // given empty prompt
       const hook = createThinkModeHook()
-      const input = createMockInput("github-copilot", "claude-opus-4-5", "")
+      const input = createMockInput("github-copilot", "claude-opus-4-6", "")
 
       // when the chat.params hook is called
       await hook["chat.params"](input, sessionID)
 
       // then should not upgrade (no think keyword)
-      expect(input.message.model?.modelID).toBe("claude-opus-4-5")
+      expect(input.message.model?.modelID).toBe("claude-opus-4-6")
     })
   })
 
diff --git a/src/hooks/think-mode/switcher.test.ts b/src/hooks/think-mode/switcher.test.ts
index 3efa98de5..9451fcb13 100644
--- a/src/hooks/think-mode/switcher.test.ts
+++ b/src/hooks/think-mode/switcher.test.ts
@@ -12,7 +12,7 @@ describe("think-mode switcher", () => {
       it("should resolve github-copilot Claude Opus to anthropic config", () => {
         // given a github-copilot provider with Claude Opus model
         const providerID = "github-copilot"
-        const modelID = "claude-opus-4-5"
+        const modelID = "claude-opus-4-6"
 
         // when getting thinking config
         const config = getThinkingConfig(providerID, modelID)
@@ -38,8 +38,8 @@ describe("think-mode switcher", () => {
       })
 
       it("should handle Claude with dots in version number", () => {
-        // given a model ID with dots (claude-opus-4.5)
-        const config = getThinkingConfig("github-copilot", "claude-opus-4.5")
+        // given a model ID with dots (claude-opus-4.6)
+        const config = getThinkingConfig("github-copilot", "claude-opus-4.6")
 
         // then should still return anthropic thinking config
         expect(config).not.toBeNull()
@@ -127,18 +127,18 @@ describe("think-mode switcher", () => {
     describe("getHighVariant with dots vs hyphens", () => {
       it("should handle dots in Claude version numbers", () => {
         // given a Claude model ID with dot format
-        const variant = getHighVariant("claude-opus-4.5")
+        const variant = getHighVariant("claude-opus-4.6")
 
         // then should return high variant with hyphen format
-        expect(variant).toBe("claude-opus-4-5-high")
+        expect(variant).toBe("claude-opus-4-6-high")
       })
 
       it("should handle hyphens in Claude version numbers", () => {
         // given a Claude model ID with hyphen format
-        const variant = getHighVariant("claude-opus-4-5")
+        const variant = getHighVariant("claude-opus-4-6")
 
         // then should return high variant
-        expect(variant).toBe("claude-opus-4-5-high")
+        expect(variant).toBe("claude-opus-4-6-high")
       })
 
       it("should handle claude-opus-4-6 high variant", () => {
@@ -177,7 +177,7 @@ describe("think-mode switcher", () => {
 
       it("should return null for already-high variants", () => {
         // given model IDs that are already high variants
-        expect(getHighVariant("claude-opus-4-5-high")).toBeNull()
+        expect(getHighVariant("claude-opus-4-6-high")).toBeNull()
         expect(getHighVariant("gpt-5-2-high")).toBeNull()
         expect(getHighVariant("gemini-3-pro-high")).toBeNull()
       })
@@ -193,7 +193,7 @@ describe("think-mode switcher", () => {
   describe("isAlreadyHighVariant", () => {
     it("should detect -high suffix", () => {
       // given model IDs with -high suffix
-      expect(isAlreadyHighVariant("claude-opus-4-5-high")).toBe(true)
+      expect(isAlreadyHighVariant("claude-opus-4-6-high")).toBe(true)
       expect(isAlreadyHighVariant("gpt-5-2-high")).toBe(true)
       expect(isAlreadyHighVariant("gemini-3-pro-high")).toBe(true)
     })
@@ -205,8 +205,8 @@ describe("think-mode switcher", () => {
 
     it("should return false for base models", () => {
       // given base model IDs without -high suffix
-      expect(isAlreadyHighVariant("claude-opus-4-5")).toBe(false)
-      expect(isAlreadyHighVariant("claude-opus-4.5")).toBe(false)
+      expect(isAlreadyHighVariant("claude-opus-4-6")).toBe(false)
+      expect(isAlreadyHighVariant("claude-opus-4.6")).toBe(false)
       expect(isAlreadyHighVariant("gpt-5.2")).toBe(false)
       expect(isAlreadyHighVariant("gemini-3-pro")).toBe(false)
     })
@@ -222,7 +222,7 @@ describe("think-mode switcher", () => {
       it("should return null for already-high variants", () => {
         // given already-high model variants
         expect(
-          getThinkingConfig("anthropic", "claude-opus-4-5-high")
+          getThinkingConfig("anthropic", "claude-opus-4-6-high")
         ).toBeNull()
         expect(getThinkingConfig("openai", "gpt-5-2-high")).toBeNull()
         expect(getThinkingConfig("google", "gemini-3-pro-high")).toBeNull()
@@ -231,7 +231,7 @@ describe("think-mode switcher", () => {
       it("should return null for already-high variants via github-copilot", () => {
         // given already-high model variants via github-copilot
         expect(
-          getThinkingConfig("github-copilot", "claude-opus-4-5-high")
+          getThinkingConfig("github-copilot", "claude-opus-4-6-high")
         ).toBeNull()
         expect(getThinkingConfig("github-copilot", "gpt-5.2-high")).toBeNull()
       })
@@ -258,7 +258,7 @@ describe("think-mode switcher", () => {
   describe("Direct provider configs (backwards compatibility)", () => {
     it("should still work for direct anthropic provider", () => {
       // given direct anthropic provider
-      const config = getThinkingConfig("anthropic", "claude-opus-4-5")
+      const config = getThinkingConfig("anthropic", "claude-opus-4-6")
 
       // then should return anthropic thinking config
       expect(config).not.toBeNull()
@@ -351,10 +351,10 @@ describe("think-mode switcher", () => {
 
       it("should handle prefixes with dots in version numbers", () => {
         // given a model ID with prefix and dots
-        const variant = getHighVariant("vertex_ai/claude-opus-4.5")
+        const variant = getHighVariant("vertex_ai/claude-opus-4.6")
 
         // then should normalize dots and preserve prefix
-        expect(variant).toBe("vertex_ai/claude-opus-4-5-high")
+        expect(variant).toBe("vertex_ai/claude-opus-4-6-high")
       })
 
       it("should handle multiple different prefixes", () => {
@@ -372,7 +372,7 @@ describe("think-mode switcher", () => {
 
       it("should return null for already-high prefixed models", () => {
         // given prefixed model IDs that are already high
-        expect(getHighVariant("vertex_ai/claude-opus-4-5-high")).toBeNull()
+        expect(getHighVariant("vertex_ai/claude-opus-4-6-high")).toBeNull()
         expect(getHighVariant("openai/gpt-5-2-high")).toBeNull()
       })
     })
@@ -380,14 +380,14 @@ describe("think-mode switcher", () => {
     describe("isAlreadyHighVariant with prefixes", () => {
       it("should detect -high suffix in prefixed models", () => {
         // given prefixed model IDs with -high suffix
-        expect(isAlreadyHighVariant("vertex_ai/claude-opus-4-5-high")).toBe(true)
+        expect(isAlreadyHighVariant("vertex_ai/claude-opus-4-6-high")).toBe(true)
         expect(isAlreadyHighVariant("openai/gpt-5-2-high")).toBe(true)
         expect(isAlreadyHighVariant("custom/gemini-3-pro-high")).toBe(true)
       })
 
       it("should return false for prefixed base models", () => {
         // given prefixed base model IDs without -high suffix
-        expect(isAlreadyHighVariant("vertex_ai/claude-opus-4-5")).toBe(false)
+        expect(isAlreadyHighVariant("vertex_ai/claude-opus-4-6")).toBe(false)
         expect(isAlreadyHighVariant("openai/gpt-5-2")).toBe(false)
       })
 
@@ -410,7 +410,7 @@ describe("think-mode switcher", () => {
       it("should work with prefixed models on known providers", () => {
         // given known provider (anthropic) with prefixed model
         // This tests that the base model name is correctly extracted for capability check
-        const config = getThinkingConfig("anthropic", "custom-prefix/claude-opus-4-5")
+        const config = getThinkingConfig("anthropic", "custom-prefix/claude-opus-4-6")
 
         // then should return thinking config (base model is capable)
         expect(config).not.toBeNull()
@@ -419,7 +419,7 @@ describe("think-mode switcher", () => {
 
       it("should return null for prefixed models that are already high", () => {
         // given prefixed already-high model
-        const config = getThinkingConfig("anthropic", "vertex_ai/claude-opus-4-5-high")
+        const config = getThinkingConfig("anthropic", "vertex_ai/claude-opus-4-6-high")
 
         // then should return null
         expect(config).toBeNull()
@@ -452,11 +452,11 @@ describe("think-mode switcher", () => {
 
       it("should not break when switching to high variant in think mode", () => {
         // given think mode switching vertex_ai/claude model to high variant
-        const original = "vertex_ai/claude-opus-4-5"
+        const original = "vertex_ai/claude-opus-4-6"
         const high = getHighVariant(original)
 
         // then the high variant should be valid
-        expect(high).toBe("vertex_ai/claude-opus-4-5-high")
+        expect(high).toBe("vertex_ai/claude-opus-4-6-high")
 
         // #and should be recognized as already high
         expect(isAlreadyHighVariant(high!)).toBe(true)
diff --git a/src/hooks/think-mode/switcher.ts b/src/hooks/think-mode/switcher.ts
index b949c2c3a..677c28b35 100644
--- a/src/hooks/think-mode/switcher.ts
+++ b/src/hooks/think-mode/switcher.ts
@@ -38,14 +38,14 @@ function extractModelPrefix(modelID: string): { prefix: string; base: string } {
 
 /**
  * Normalizes model IDs to use consistent hyphen formatting.
- * GitHub Copilot may use dots (claude-opus-4.5) but our maps use hyphens (claude-opus-4-5).
+ * GitHub Copilot may use dots (claude-opus-4.6) but our maps use hyphens (claude-opus-4-6).
  * This ensures lookups work regardless of format.
  *
  * @example
- * normalizeModelID("claude-opus-4.5") // "claude-opus-4-5"
+ * normalizeModelID("claude-opus-4.6") // "claude-opus-4-6"
  * normalizeModelID("gemini-3.5-pro") // "gemini-3-5-pro"
  * normalizeModelID("gpt-5.2") // "gpt-5-2"
- * normalizeModelID("vertex_ai/claude-opus-4.5") // "vertex_ai/claude-opus-4-5"
+ * normalizeModelID("vertex_ai/claude-opus-4.6") // "vertex_ai/claude-opus-4-6"
  */
 function normalizeModelID(modelID: string): string {
   // Replace dots with hyphens when followed by a digit
@@ -59,10 +59,10 @@ function normalizeModelID(modelID: string): string {
  * model provider (Anthropic, Google, OpenAI).
  *
  * @example
- * resolveProvider("github-copilot", "claude-opus-4-5") // "anthropic"
+ * resolveProvider("github-copilot", "claude-opus-4-6") // "anthropic"
  * resolveProvider("github-copilot", "gemini-3-pro") // "google"
  * resolveProvider("github-copilot", "gpt-5.2") // "openai"
- * resolveProvider("anthropic", "claude-opus-4-5") // "anthropic" (unchanged)
+ * resolveProvider("anthropic", "claude-opus-4-6") // "anthropic" (unchanged)
  */
 function resolveProvider(providerID: string, modelID: string): string {
   // GitHub Copilot is a proxy - infer actual provider from model name
@@ -89,7 +89,6 @@ const HIGH_VARIANT_MAP: Record<string, string> = {
   // Claude
   "claude-sonnet-4-5": "claude-sonnet-4-5-high",
   "claude-opus-4-6": "claude-opus-4-6-high",
-  "claude-opus-4-5": "claude-opus-4-5-high",
    // Gemini
    "gemini-3-pro": "gemini-3-pro-high",
    "gemini-3-pro-low": "gemini-3-pro-high",
diff --git a/src/index.ts b/src/index.ts
index baf4f9590..c62c68b07 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -849,7 +849,7 @@ const OhMyOpenCodePlugin: Plugin = async (ctx) => {
       await compactionContextInjector({
         sessionID: input.sessionID,
         providerID: "anthropic",
-        modelID: "claude-opus-4-5",
+        modelID: "claude-opus-4-6",
         usageRatio: 0.8,
         directory: ctx.directory,
       });
diff --git a/src/plugin-handlers/config-handler.test.ts b/src/plugin-handlers/config-handler.test.ts
index 6f6fa3aed..2580fe5e3 100644
--- a/src/plugin-handlers/config-handler.test.ts
+++ b/src/plugin-handlers/config-handler.test.ts
@@ -63,7 +63,7 @@ beforeEach(() => {
   spyOn(mcpModule, "createBuiltinMcps" as any).mockReturnValue({})
 
   spyOn(shared, "log" as any).mockImplementation(() => {})
-  spyOn(shared, "fetchAvailableModels" as any).mockResolvedValue(new Set(["anthropic/claude-opus-4-5"]))
+  spyOn(shared, "fetchAvailableModels" as any).mockResolvedValue(new Set(["anthropic/claude-opus-4-6"]))
   spyOn(shared, "readConnectedProvidersCache" as any).mockReturnValue(null)
 
   spyOn(configDir, "getOpenCodeConfigPaths" as any).mockReturnValue({
@@ -73,7 +73,7 @@ beforeEach(() => {
 
   spyOn(permissionCompat, "migrateAgentConfig" as any).mockImplementation((config: Record<string, unknown>) => config)
 
-  spyOn(modelResolver, "resolveModelWithFallback" as any).mockReturnValue({ model: "anthropic/claude-opus-4-5" })
+  spyOn(modelResolver, "resolveModelWithFallback" as any).mockReturnValue({ model: "anthropic/claude-opus-4-6" })
 })
 
 afterEach(() => {
@@ -123,7 +123,7 @@ describe("Plan agent demote behavior", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -154,7 +154,7 @@ describe("Plan agent demote behavior", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {
         plan: {
           name: "plan",
@@ -191,7 +191,7 @@ describe("Plan agent demote behavior", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {
         plan: {
           name: "plan",
@@ -228,7 +228,7 @@ describe("Plan agent demote behavior", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -263,7 +263,7 @@ describe("Agent permission defaults", () => {
     })
     const pluginConfig: OhMyOpenCodeConfig = {}
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -295,7 +295,7 @@ describe("Prometheus category config resolution", () => {
 
     // then
     expect(config).toBeDefined()
-    expect(config?.model).toBe("openai/gpt-5.2-codex")
+    expect(config?.model).toBe("openai/gpt-5.3-codex")
     expect(config?.variant).toBe("xhigh")
   })
 
@@ -355,7 +355,7 @@ describe("Prometheus category config resolution", () => {
 
     // then - falls back to DEFAULT_CATEGORIES
     expect(config).toBeDefined()
-    expect(config?.model).toBe("openai/gpt-5.2-codex")
+    expect(config?.model).toBe("openai/gpt-5.3-codex")
     expect(config?.variant).toBe("xhigh")
   })
 
@@ -406,7 +406,7 @@ describe("Prometheus direct override priority over category", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -446,7 +446,7 @@ describe("Prometheus direct override priority over category", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -487,7 +487,7 @@ describe("Prometheus direct override priority over category", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -522,7 +522,7 @@ describe("Prometheus direct override priority over category", () => {
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const handler = createConfigHandler({
@@ -560,7 +560,7 @@ describe("Deadlock prevention - fetchAvailableModels must not receive client", (
       },
     }
     const config: Record<string, unknown> = {
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
       agent: {},
     }
     const mockClient = {
diff --git a/src/shared/agent-config-integration.test.ts b/src/shared/agent-config-integration.test.ts
index 160410475..e663da9fc 100644
--- a/src/shared/agent-config-integration.test.ts
+++ b/src/shared/agent-config-integration.test.ts
@@ -8,9 +8,9 @@ describe("Agent Config Integration", () => {
     test("migrates old format agent keys to lowercase", () => {
       // given - config with old format keys
       const oldConfig = {
-        Sisyphus: { model: "anthropic/claude-opus-4-5" },
-        Atlas: { model: "anthropic/claude-opus-4-5" },
-        "Prometheus (Planner)": { model: "anthropic/claude-opus-4-5" },
+        Sisyphus: { model: "anthropic/claude-opus-4-6" },
+        Atlas: { model: "anthropic/claude-opus-4-6" },
+        "Prometheus (Planner)": { model: "anthropic/claude-opus-4-6" },
         "Metis (Plan Consultant)": { model: "anthropic/claude-sonnet-4-5" },
         "Momus (Plan Reviewer)": { model: "anthropic/claude-sonnet-4-5" },
       }
@@ -33,9 +33,9 @@ describe("Agent Config Integration", () => {
       expect(result.migrated).not.toHaveProperty("Momus (Plan Reviewer)")
 
       // then - values are preserved
-      expect(result.migrated.sisyphus).toEqual({ model: "anthropic/claude-opus-4-5" })
-      expect(result.migrated.atlas).toEqual({ model: "anthropic/claude-opus-4-5" })
-      expect(result.migrated.prometheus).toEqual({ model: "anthropic/claude-opus-4-5" })
+      expect(result.migrated.sisyphus).toEqual({ model: "anthropic/claude-opus-4-6" })
+      expect(result.migrated.atlas).toEqual({ model: "anthropic/claude-opus-4-6" })
+      expect(result.migrated.prometheus).toEqual({ model: "anthropic/claude-opus-4-6" })
       
       // then - changed flag is true
       expect(result.changed).toBe(true)
@@ -44,7 +44,7 @@ describe("Agent Config Integration", () => {
     test("preserves already lowercase keys", () => {
       // given - config with lowercase keys
       const config = {
-        sisyphus: { model: "anthropic/claude-opus-4-5" },
+        sisyphus: { model: "anthropic/claude-opus-4-6" },
         oracle: { model: "openai/gpt-5.2" },
         librarian: { model: "opencode/glm-4.7-free" },
       }
@@ -62,9 +62,9 @@ describe("Agent Config Integration", () => {
     test("handles mixed case config", () => {
       // given - config with mixed old and new format
       const mixedConfig = {
-        Sisyphus: { model: "anthropic/claude-opus-4-5" },
+        Sisyphus: { model: "anthropic/claude-opus-4-6" },
         oracle: { model: "openai/gpt-5.2" },
-        "Prometheus (Planner)": { model: "anthropic/claude-opus-4-5" },
+        "Prometheus (Planner)": { model: "anthropic/claude-opus-4-6" },
         librarian: { model: "opencode/glm-4.7-free" },
       }
 
@@ -172,8 +172,8 @@ describe("Agent Config Integration", () => {
     test("old config migrates and displays correctly", () => {
       // given - old format config
       const oldConfig = {
-        Sisyphus: { model: "anthropic/claude-opus-4-5", temperature: 0.1 },
-        "Prometheus (Planner)": { model: "anthropic/claude-opus-4-5" },
+        Sisyphus: { model: "anthropic/claude-opus-4-6", temperature: 0.1 },
+        "Prometheus (Planner)": { model: "anthropic/claude-opus-4-6" },
       }
 
       // when - config is migrated
@@ -192,15 +192,15 @@ describe("Agent Config Integration", () => {
       expect(prometheusDisplay).toBe("Prometheus (Plan Builder)")
 
       // then - config values are preserved
-      expect(result.migrated.sisyphus).toEqual({ model: "anthropic/claude-opus-4-5", temperature: 0.1 })
-      expect(result.migrated.prometheus).toEqual({ model: "anthropic/claude-opus-4-5" })
+      expect(result.migrated.sisyphus).toEqual({ model: "anthropic/claude-opus-4-6", temperature: 0.1 })
+      expect(result.migrated.prometheus).toEqual({ model: "anthropic/claude-opus-4-6" })
     })
 
     test("new config works without migration", () => {
       // given - new format config (already lowercase)
       const newConfig = {
-        sisyphus: { model: "anthropic/claude-opus-4-5" },
-        atlas: { model: "anthropic/claude-opus-4-5" },
+        sisyphus: { model: "anthropic/claude-opus-4-6" },
+        atlas: { model: "anthropic/claude-opus-4-6" },
       }
 
       // when - migration is applied (should be no-op)
diff --git a/src/shared/agent-variant.test.ts b/src/shared/agent-variant.test.ts
index 16c46e913..b36bade3b 100644
--- a/src/shared/agent-variant.test.ts
+++ b/src/shared/agent-variant.test.ts
@@ -84,14 +84,14 @@ describe("applyAgentVariant", () => {
 
 describe("resolveVariantForModel", () => {
   test("returns agent override variant when configured", () => {
-    // given - use a model in sisyphus chain (claude-opus-4-5 has default variant "max")
+    // given - use a model in sisyphus chain (claude-opus-4-6 has default variant "max")
     // to verify override takes precedence over fallback chain
     const config = {
       agents: {
         sisyphus: { variant: "high" },
       },
     } as OhMyOpenCodeConfig
-    const model = { providerID: "anthropic", modelID: "claude-opus-4-5" }
+    const model = { providerID: "anthropic", modelID: "claude-opus-4-6" }
 
     // when
     const variant = resolveVariantForModel(config, "sisyphus", model)
@@ -103,7 +103,7 @@ describe("resolveVariantForModel", () => {
   test("returns correct variant for anthropic provider", () => {
     // given
     const config = {} as OhMyOpenCodeConfig
-    const model = { providerID: "anthropic", modelID: "claude-opus-4-5" }
+    const model = { providerID: "anthropic", modelID: "claude-opus-4-6" }
 
     // when
     const variant = resolveVariantForModel(config, "sisyphus", model)
@@ -113,9 +113,9 @@ describe("resolveVariantForModel", () => {
   })
 
   test("returns correct variant for openai provider (hephaestus agent)", () => {
-    // #given hephaestus has openai/gpt-5.2-codex with variant "medium" in its chain
+    // #given hephaestus has openai/gpt-5.3-codex with variant "medium" in its chain
     const config = {} as OhMyOpenCodeConfig
-    const model = { providerID: "openai", modelID: "gpt-5.2-codex" }
+    const model = { providerID: "openai", modelID: "gpt-5.3-codex" }
 
     // #when
     const variant = resolveVariantForModel(config, "hephaestus", model)
@@ -151,7 +151,7 @@ describe("resolveVariantForModel", () => {
   test("returns undefined for unknown agent", () => {
     // given
     const config = {} as OhMyOpenCodeConfig
-    const model = { providerID: "anthropic", modelID: "claude-opus-4-5" }
+    const model = { providerID: "anthropic", modelID: "claude-opus-4-6" }
 
     // when
     const variant = resolveVariantForModel(config, "nonexistent-agent", model)
@@ -179,7 +179,7 @@ describe("resolveVariantForModel", () => {
         "custom-agent": { category: "ultrabrain" },
       },
     } as OhMyOpenCodeConfig
-    const model = { providerID: "openai", modelID: "gpt-5.2-codex" }
+    const model = { providerID: "openai", modelID: "gpt-5.3-codex" }
 
     // when
     const variant = resolveVariantForModel(config, "custom-agent", model)
@@ -203,7 +203,7 @@ describe("resolveVariantForModel", () => {
   test("returns correct variant for oracle agent with anthropic", () => {
     // given
     const config = {} as OhMyOpenCodeConfig
-    const model = { providerID: "anthropic", modelID: "claude-opus-4-5" }
+    const model = { providerID: "anthropic", modelID: "claude-opus-4-6" }
 
     // when
     const variant = resolveVariantForModel(config, "oracle", model)
diff --git a/src/shared/migration.test.ts b/src/shared/migration.test.ts
index b2a9836a5..2ba28dc71 100644
--- a/src/shared/migration.test.ts
+++ b/src/shared/migration.test.ts
@@ -15,7 +15,7 @@ describe("migrateAgentNames", () => {
   test("migrates legacy OmO names to lowercase", () => {
     // given: Config with legacy OmO agent names
     const agents = {
-      omo: { model: "anthropic/claude-opus-4-5" },
+      omo: { model: "anthropic/claude-opus-4-6" },
       OmO: { temperature: 0.5 },
       "OmO-Plan": { prompt: "custom prompt" },
     }
@@ -84,7 +84,7 @@ describe("migrateAgentNames", () => {
   test("migrates orchestrator-sisyphus to atlas", () => {
     // given: Config with legacy orchestrator-sisyphus agent name
     const agents = {
-      "orchestrator-sisyphus": { model: "anthropic/claude-opus-4-5" },
+      "orchestrator-sisyphus": { model: "anthropic/claude-opus-4-6" },
     }
 
     // when: Migrate agent names
@@ -92,14 +92,14 @@ describe("migrateAgentNames", () => {
 
     // then: orchestrator-sisyphus should be migrated to atlas
     expect(changed).toBe(true)
-    expect(migrated["atlas"]).toEqual({ model: "anthropic/claude-opus-4-5" })
+    expect(migrated["atlas"]).toEqual({ model: "anthropic/claude-opus-4-6" })
     expect(migrated["orchestrator-sisyphus"]).toBeUndefined()
   })
 
   test("migrates lowercase atlas to atlas", () => {
     // given: Config with lowercase atlas agent name
     const agents = {
-      atlas: { model: "anthropic/claude-opus-4-5" },
+      atlas: { model: "anthropic/claude-opus-4-6" },
     }
 
     // when: Migrate agent names
@@ -107,7 +107,7 @@ describe("migrateAgentNames", () => {
 
     // then: lowercase atlas should remain atlas (no change needed)
     expect(changed).toBe(false)
-    expect(migrated["atlas"]).toEqual({ model: "anthropic/claude-opus-4-5" })
+    expect(migrated["atlas"]).toEqual({ model: "anthropic/claude-opus-4-6" })
   })
 
   test("migrates Sisyphus variants to lowercase", () => {
@@ -470,7 +470,7 @@ describe("migrateAgentConfigToCategory", () => {
       { model: "google/gemini-3-flash" },
       { model: "openai/gpt-5.2" },
       { model: "anthropic/claude-haiku-4-5" },
-      { model: "anthropic/claude-opus-4-5" },
+      { model: "anthropic/claude-opus-4-6" },
       { model: "anthropic/claude-sonnet-4-5" },
     ]
 
@@ -550,7 +550,7 @@ describe("shouldDeleteAgentConfig", () => {
     // given: Config with custom model override
     const config = {
       category: "visual-engineering",
-      model: "anthropic/claude-opus-4-5",
+      model: "anthropic/claude-opus-4-6",
     }
 
     // when: Check if config should be deleted
diff --git a/src/shared/migration.ts b/src/shared/migration.ts
index e50042469..096a24869 100644
--- a/src/shared/migration.ts
+++ b/src/shared/migration.ts
@@ -85,7 +85,7 @@ export const MODEL_TO_CATEGORY_MAP: Record<string, string> = {
   "google/gemini-3-flash": "writing",
   "openai/gpt-5.2": "ultrabrain",
   "anthropic/claude-haiku-4-5": "quick",
-  "anthropic/claude-opus-4-5": "unspecified-high",
+  "anthropic/claude-opus-4-6": "unspecified-high",
   "anthropic/claude-sonnet-4-5": "unspecified-low",
 }
 
diff --git a/src/shared/model-availability.test.ts b/src/shared/model-availability.test.ts
index d831ac279..80d637c74 100644
--- a/src/shared/model-availability.test.ts
+++ b/src/shared/model-availability.test.ts
@@ -33,7 +33,7 @@ describe("fetchAvailableModels", () => {
   it("#given cache file with models #when fetchAvailableModels called with connectedProviders #then returns Set of model IDs", async () => {
     writeModelsCache({
       openai: { id: "openai", models: { "gpt-5.2": { id: "gpt-5.2" } } },
-      anthropic: { id: "anthropic", models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+      anthropic: { id: "anthropic", models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
       google: { id: "google", models: { "gemini-3-pro": { id: "gemini-3-pro" } } },
     })
 
@@ -44,7 +44,7 @@ describe("fetchAvailableModels", () => {
     expect(result).toBeInstanceOf(Set)
     expect(result.size).toBe(3)
     expect(result.has("openai/gpt-5.2")).toBe(true)
-    expect(result.has("anthropic/claude-opus-4-5")).toBe(true)
+    expect(result.has("anthropic/claude-opus-4-6")).toBe(true)
     expect(result.has("google/gemini-3-pro")).toBe(true)
   })
 
@@ -67,7 +67,7 @@ describe("fetchAvailableModels", () => {
       model: {
         list: async () => ({
           data: [
-            { id: "gpt-5.2-codex", provider: "openai" },
+            { id: "gpt-5.3-codex", provider: "openai" },
             { id: "gemini-3-pro", provider: "google" },
           ],
         }),
@@ -77,7 +77,7 @@ describe("fetchAvailableModels", () => {
     const result = await fetchAvailableModels(client)
 
     expect(result).toBeInstanceOf(Set)
-    expect(result.has("openai/gpt-5.2-codex")).toBe(true)
+    expect(result.has("openai/gpt-5.3-codex")).toBe(true)
     expect(result.has("google/gemini-3-pro")).toBe(false)
   })
 
@@ -96,7 +96,7 @@ describe("fetchAvailableModels", () => {
       model: {
         list: async () => ({
           data: [
-            { id: "gpt-5.2-codex", provider: "openai" },
+            { id: "gpt-5.3-codex", provider: "openai" },
             { id: "gemini-3-pro", provider: "google" },
           ],
         }),
@@ -106,14 +106,14 @@ describe("fetchAvailableModels", () => {
     const result = await fetchAvailableModels(client, { connectedProviders: ["openai", "google"] })
 
     expect(result).toBeInstanceOf(Set)
-    expect(result.has("openai/gpt-5.2-codex")).toBe(true)
+    expect(result.has("openai/gpt-5.3-codex")).toBe(true)
     expect(result.has("google/gemini-3-pro")).toBe(true)
   })
 
   it("#given cache read twice #when second call made with same providers #then reads fresh each time", async () => {
     writeModelsCache({
       openai: { id: "openai", models: { "gpt-5.2": { id: "gpt-5.2" } } },
-      anthropic: { id: "anthropic", models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+      anthropic: { id: "anthropic", models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
     })
 
     const result1 = await fetchAvailableModels(undefined, { connectedProviders: ["openai"] })
@@ -134,7 +134,7 @@ describe("fetchAvailableModels", () => {
 
   it("#given cache file with various providers #when fetchAvailableModels called with all providers #then extracts all IDs correctly", async () => {
     writeModelsCache({
-      openai: { id: "openai", models: { "gpt-5.2-codex": { id: "gpt-5.2-codex" } } },
+      openai: { id: "openai", models: { "gpt-5.3-codex": { id: "gpt-5.3-codex" } } },
       anthropic: { id: "anthropic", models: { "claude-sonnet-4-5": { id: "claude-sonnet-4-5" } } },
       google: { id: "google", models: { "gemini-3-flash": { id: "gemini-3-flash" } } },
       opencode: { id: "opencode", models: { "gpt-5-nano": { id: "gpt-5-nano" } } },
@@ -145,7 +145,7 @@ describe("fetchAvailableModels", () => {
     })
 
     expect(result.size).toBe(4)
-    expect(result.has("openai/gpt-5.2-codex")).toBe(true)
+    expect(result.has("openai/gpt-5.3-codex")).toBe(true)
     expect(result.has("anthropic/claude-sonnet-4-5")).toBe(true)
     expect(result.has("google/gemini-3-flash")).toBe(true)
     expect(result.has("opencode/gpt-5-nano")).toBe(true)
@@ -159,8 +159,8 @@ describe("fuzzyMatchModel", () => {
 	it("should match substring in model name", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"openai/gpt-5.2-codex",
-			"anthropic/claude-opus-4-5",
+			"openai/gpt-5.3-codex",
+			"anthropic/claude-opus-4-6",
 		])
 		const result = fuzzyMatchModel("gpt-5.2", available)
 		expect(result).toBe("openai/gpt-5.2")
@@ -185,7 +185,7 @@ describe("fuzzyMatchModel", () => {
 	it("should prefer exact match over substring match", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"openai/gpt-5.2-codex",
+			"openai/gpt-5.3-codex",
 			"openai/gpt-5.2-ultra",
 		])
 		const result = fuzzyMatchModel("gpt-5.2", available)
@@ -207,13 +207,13 @@ describe("fuzzyMatchModel", () => {
 	// given available models with claude variants
 	// when searching for claude-opus
 	// then return matching claude-opus model
-	it("should match claude-opus to claude-opus-4-5", () => {
+	it("should match claude-opus to claude-opus-4-6", () => {
 		const available = new Set([
-			"anthropic/claude-opus-4-5",
+			"anthropic/claude-opus-4-6",
 			"anthropic/claude-sonnet-4-5",
 		])
 		const result = fuzzyMatchModel("claude-opus", available)
-		expect(result).toBe("anthropic/claude-opus-4-5")
+		expect(result).toBe("anthropic/claude-opus-4-6")
 	})
 
 	// given available models from multiple providers
@@ -222,7 +222,7 @@ describe("fuzzyMatchModel", () => {
 	it("should filter by provider when providers array is given", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"anthropic/claude-opus-4-5",
+			"anthropic/claude-opus-4-6",
 			"google/gemini-3",
 		])
 		const result = fuzzyMatchModel("gpt", available, ["openai"])
@@ -235,7 +235,7 @@ describe("fuzzyMatchModel", () => {
 	it("should return null when provider filter excludes all matches", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"anthropic/claude-opus-4-5",
+			"anthropic/claude-opus-4-6",
 		])
 		const result = fuzzyMatchModel("claude", available, ["openai"])
 		expect(result).toBeNull()
@@ -247,7 +247,7 @@ describe("fuzzyMatchModel", () => {
 	it("should return null when no match found", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"anthropic/claude-opus-4-5",
+			"anthropic/claude-opus-4-6",
 		])
 		const result = fuzzyMatchModel("gemini", available)
 		expect(result).toBeNull()
@@ -259,7 +259,7 @@ describe("fuzzyMatchModel", () => {
 	it("should match case-insensitively", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"anthropic/claude-opus-4-5",
+			"anthropic/claude-opus-4-6",
 		])
 		const result = fuzzyMatchModel("GPT-5.2", available)
 		expect(result).toBe("openai/gpt-5.2")
@@ -270,11 +270,11 @@ describe("fuzzyMatchModel", () => {
 	// then return exact match first
 	it("should prioritize exact match over longer variants", () => {
 		const available = new Set([
-			"anthropic/claude-opus-4-5",
-			"anthropic/claude-opus-4-5-extended",
+			"anthropic/claude-opus-4-6",
+			"anthropic/claude-opus-4-6-extended",
 		])
-		const result = fuzzyMatchModel("claude-opus-4-5", available)
-		expect(result).toBe("anthropic/claude-opus-4-5")
+		const result = fuzzyMatchModel("claude-opus-4-6", available)
+		expect(result).toBe("anthropic/claude-opus-4-6")
 	})
 
 	// given available models with similar model IDs (e.g., glm-4.7 and glm-4.7-free)
@@ -319,7 +319,7 @@ describe("fuzzyMatchModel", () => {
 	it("should search all specified providers", () => {
 		const available = new Set([
 			"openai/gpt-5.2",
-			"anthropic/claude-opus-4-5",
+			"anthropic/claude-opus-4-6",
 			"google/gemini-3",
 		])
 		const result = fuzzyMatchModel("gpt", available, ["openai", "google"])
@@ -464,7 +464,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 	it("should filter models by connected providers", async () => {
 		writeModelsCache({
 			openai: { models: { "gpt-5.2": { id: "gpt-5.2" } } },
-			anthropic: { models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+			anthropic: { models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
 			google: { models: { "gemini-3-pro": { id: "gemini-3-pro" } } },
 		})
 
@@ -473,7 +473,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 		})
 
 		expect(result.size).toBe(1)
-		expect(result.has("anthropic/claude-opus-4-5")).toBe(true)
+		expect(result.has("anthropic/claude-opus-4-6")).toBe(true)
 		expect(result.has("openai/gpt-5.2")).toBe(false)
 		expect(result.has("google/gemini-3-pro")).toBe(false)
 	})
@@ -484,7 +484,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 	it("should filter models by multiple connected providers", async () => {
 		writeModelsCache({
 			openai: { models: { "gpt-5.2": { id: "gpt-5.2" } } },
-			anthropic: { models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+			anthropic: { models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
 			google: { models: { "gemini-3-pro": { id: "gemini-3-pro" } } },
 		})
 
@@ -493,7 +493,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 		})
 
 		expect(result.size).toBe(2)
-		expect(result.has("anthropic/claude-opus-4-5")).toBe(true)
+		expect(result.has("anthropic/claude-opus-4-6")).toBe(true)
 		expect(result.has("google/gemini-3-pro")).toBe(true)
 		expect(result.has("openai/gpt-5.2")).toBe(false)
 	})
@@ -504,7 +504,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 	it("should return empty set when connectedProviders is empty", async () => {
 		writeModelsCache({
 			openai: { models: { "gpt-5.2": { id: "gpt-5.2" } } },
-			anthropic: { models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+			anthropic: { models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
 		})
 
 		const result = await fetchAvailableModels(undefined, {
@@ -520,7 +520,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 	it("should return empty set when connectedProviders not specified", async () => {
 		writeModelsCache({
 			openai: { models: { "gpt-5.2": { id: "gpt-5.2" } } },
-			anthropic: { models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+			anthropic: { models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
 		})
 
 		const result = await fetchAvailableModels()
@@ -549,7 +549,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 	it("should return models from providers that exist in both cache and connected list", async () => {
 		writeModelsCache({
 			openai: { models: { "gpt-5.2": { id: "gpt-5.2" } } },
-			anthropic: { models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+			anthropic: { models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
 		})
 
 		const result = await fetchAvailableModels(undefined, {
@@ -557,7 +557,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 		})
 
 		expect(result.size).toBe(1)
-		expect(result.has("anthropic/claude-opus-4-5")).toBe(true)
+		expect(result.has("anthropic/claude-opus-4-6")).toBe(true)
 	})
 
 	// given filtered fetch
@@ -566,7 +566,7 @@ describe("fetchAvailableModels with connected providers filtering", () => {
 	it("should not cache filtered results", async () => {
 		writeModelsCache({
 			openai: { models: { "gpt-5.2": { id: "gpt-5.2" } } },
-			anthropic: { models: { "claude-opus-4-5": { id: "claude-opus-4-5" } } },
+			anthropic: { models: { "claude-opus-4-6": { id: "claude-opus-4-6" } } },
 		})
 
 		// First call with anthropic
@@ -641,13 +641,13 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 		writeProviderModelsCache({
 			models: {
 				opencode: ["glm-4.7-free", "gpt-5-nano"],
-				anthropic: ["claude-opus-4-5"]
+				anthropic: ["claude-opus-4-6"]
 			},
 			connected: ["opencode", "anthropic"]
 		})
 		writeModelsCache({
 			opencode: { models: { "glm-4.7-free": {}, "gpt-5-nano": {}, "gpt-5.2": {} } },
-			anthropic: { models: { "claude-opus-4-5": {}, "claude-sonnet-4-5": {} } }
+			anthropic: { models: { "claude-opus-4-6": {}, "claude-sonnet-4-5": {} } }
 		})
 
 		const result = await fetchAvailableModels(undefined, {
@@ -657,7 +657,7 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 		expect(result.size).toBe(3)
 		expect(result.has("opencode/glm-4.7-free")).toBe(true)
 		expect(result.has("opencode/gpt-5-nano")).toBe(true)
-		expect(result.has("anthropic/claude-opus-4-5")).toBe(true)
+		expect(result.has("anthropic/claude-opus-4-6")).toBe(true)
 		expect(result.has("opencode/gpt-5.2")).toBe(false)
 		expect(result.has("anthropic/claude-sonnet-4-5")).toBe(false)
 	})
@@ -708,7 +708,7 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 		writeProviderModelsCache({
 			models: {
 				opencode: ["glm-4.7-free"],
-				anthropic: ["claude-opus-4-5"],
+				anthropic: ["claude-opus-4-6"],
 				google: ["gemini-3-pro"]
 			},
 			connected: ["opencode", "anthropic", "google"]
@@ -720,7 +720,7 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 
 		expect(result.size).toBe(1)
 		expect(result.has("opencode/glm-4.7-free")).toBe(true)
-		expect(result.has("anthropic/claude-opus-4-5")).toBe(false)
+		expect(result.has("anthropic/claude-opus-4-6")).toBe(false)
 		expect(result.has("google/gemini-3-pro")).toBe(false)
 	})
 
@@ -747,7 +747,7 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 	it("should handle mixed string[] and object[] formats across providers", async () => {
 		writeProviderModelsCache({
 			models: {
-				anthropic: ["claude-opus-4-5", "claude-sonnet-4-5"],
+				anthropic: ["claude-opus-4-6", "claude-sonnet-4-5"],
 				ollama: [
 					{ id: "ministral-3:14b-32k-agent", provider: "ollama" },
 					{ id: "qwen3-coder:32k-agent", provider: "ollama" }
@@ -761,7 +761,7 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 		})
 
 		expect(result.size).toBe(4)
-		expect(result.has("anthropic/claude-opus-4-5")).toBe(true)
+		expect(result.has("anthropic/claude-opus-4-6")).toBe(true)
 		expect(result.has("anthropic/claude-sonnet-4-5")).toBe(true)
 		expect(result.has("ollama/ministral-3:14b-32k-agent")).toBe(true)
 		expect(result.has("ollama/qwen3-coder:32k-agent")).toBe(true)
@@ -794,10 +794,10 @@ describe("fetchAvailableModels with provider-models cache (whitelist-filtered)",
 describe("isModelAvailable", () => {
 	it("returns true when model exists via fuzzy match", () => {
 		// given
-		const available = new Set(["openai/gpt-5.2-codex", "anthropic/claude-opus-4-5"])
+		const available = new Set(["openai/gpt-5.3-codex", "anthropic/claude-opus-4-6"])
 
 		// when
-		const result = isModelAvailable("gpt-5.2-codex", available)
+		const result = isModelAvailable("gpt-5.3-codex", available)
 
 		// then
 		expect(result).toBe(true)
@@ -805,10 +805,10 @@ describe("isModelAvailable", () => {
 
 	it("returns false when model not found", () => {
 		// given
-		const available = new Set(["anthropic/claude-opus-4-5"])
+		const available = new Set(["anthropic/claude-opus-4-6"])
 
 		// when
-		const result = isModelAvailable("gpt-5.2-codex", available)
+		const result = isModelAvailable("gpt-5.3-codex", available)
 
 		// then
 		expect(result).toBe(false)
@@ -819,7 +819,7 @@ describe("isModelAvailable", () => {
 		const available = new Set<string>()
 
 		// when
-		const result = isModelAvailable("gpt-5.2-codex", available)
+		const result = isModelAvailable("gpt-5.3-codex", available)
 
 		// then
 		expect(result).toBe(false)
diff --git a/src/shared/model-availability.ts b/src/shared/model-availability.ts
index f895d892b..6fa2fb173 100644
--- a/src/shared/model-availability.ts
+++ b/src/shared/model-availability.ts
@@ -20,7 +20,7 @@ import { readProviderModelsCache, hasProviderModelsCache, readConnectedProviders
  * If providers array is given, only models starting with "provider/" are considered.
  * 
  * @example
- * const available = new Set(["openai/gpt-5.2", "openai/gpt-5.2-codex", "anthropic/claude-opus-4-5"])
+ * const available = new Set(["openai/gpt-5.2", "openai/gpt-5.3-codex", "anthropic/claude-opus-4-6"])
  * fuzzyMatchModel("gpt-5.2", available) // → "openai/gpt-5.2"
  * fuzzyMatchModel("claude", available, ["openai"]) // → null (provider filter excludes anthropic)
  */
@@ -105,7 +105,7 @@ export function fuzzyMatchModel(
 /**
  * Check if a target model is available (fuzzy match by model name, no provider filtering)
  * 
- * @param targetModel - Model name to check (e.g., "gpt-5.2-codex")
+ * @param targetModel - Model name to check (e.g., "gpt-5.3-codex")
  * @param availableModels - Set of available models in "provider/model" format
  * @returns true if model is available, false otherwise
  */
diff --git a/src/shared/model-requirements.test.ts b/src/shared/model-requirements.test.ts
index c332e544a..5ee4743e7 100644
--- a/src/shared/model-requirements.test.ts
+++ b/src/shared/model-requirements.test.ts
@@ -23,12 +23,12 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
     expect(primary.variant).toBe("high")
   })
 
-  test("sisyphus has claude-opus-4-6 as primary before claude-opus-4-5 and requiresAnyModel", () => {
+  test("sisyphus has claude-opus-4-6 as primary before claude-opus-4-6 and requiresAnyModel", () => {
     // #given - sisyphus agent requirement
     const sisyphus = AGENT_MODEL_REQUIREMENTS["sisyphus"]
 
     // #when - accessing Sisyphus requirement
-    // #then - fallbackChain has claude-opus-4-6 first, claude-opus-4-5 second, glm-4.7-free last
+    // #then - fallbackChain has claude-opus-4-6 first, claude-opus-4-6 second, glm-4.7-free last
     expect(sisyphus).toBeDefined()
     expect(sisyphus.fallbackChain).toBeArray()
     expect(sisyphus.fallbackChain).toHaveLength(6)
@@ -41,7 +41,7 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
 
     const secondary = sisyphus.fallbackChain[1]
     expect(secondary.providers[0]).toBe("anthropic")
-    expect(secondary.model).toBe("claude-opus-4-5")
+    expect(secondary.model).toBe("claude-opus-4-6")
     expect(secondary.variant).toBe("max")
 
     const last = sisyphus.fallbackChain[5]
@@ -103,12 +103,12 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
     expect(primary.model).toBe("gemini-3-flash")
   })
 
-  test("prometheus has claude-opus-4-6 as primary before claude-opus-4-5", () => {
+  test("prometheus has claude-opus-4-6 as primary before claude-opus-4-6", () => {
     // #given - prometheus agent requirement
     const prometheus = AGENT_MODEL_REQUIREMENTS["prometheus"]
 
     // #when - accessing Prometheus requirement
-    // #then - claude-opus-4-6 is first, claude-opus-4-5 is second
+    // #then - claude-opus-4-6 is first, claude-opus-4-6 is second
     expect(prometheus).toBeDefined()
     expect(prometheus.fallbackChain).toBeArray()
     expect(prometheus.fallbackChain.length).toBeGreaterThan(1)
@@ -119,17 +119,17 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
     expect(primary.variant).toBe("max")
 
     const secondary = prometheus.fallbackChain[1]
-    expect(secondary.model).toBe("claude-opus-4-5")
+    expect(secondary.model).toBe("claude-opus-4-6")
     expect(secondary.providers[0]).toBe("anthropic")
     expect(secondary.variant).toBe("max")
   })
 
-  test("metis has claude-opus-4-6 as primary before claude-opus-4-5", () => {
+  test("metis has claude-opus-4-6 as primary before claude-opus-4-6", () => {
     // #given - metis agent requirement
     const metis = AGENT_MODEL_REQUIREMENTS["metis"]
 
     // #when - accessing Metis requirement
-    // #then - claude-opus-4-6 is first, claude-opus-4-5 is second
+    // #then - claude-opus-4-6 is first, claude-opus-4-6 is second
     expect(metis).toBeDefined()
     expect(metis.fallbackChain).toBeArray()
     expect(metis.fallbackChain.length).toBeGreaterThan(1)
@@ -140,7 +140,7 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
     expect(primary.variant).toBe("max")
 
     const secondary = metis.fallbackChain[1]
-    expect(secondary.model).toBe("claude-opus-4-5")
+    expect(secondary.model).toBe("claude-opus-4-6")
     expect(secondary.providers[0]).toBe("anthropic")
     expect(secondary.variant).toBe("max")
   })
@@ -224,35 +224,35 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
 })
 
 describe("CATEGORY_MODEL_REQUIREMENTS", () => {
-  test("ultrabrain has valid fallbackChain with gpt-5.2-codex as primary", () => {
+  test("ultrabrain has valid fallbackChain with gpt-5.3-codex as primary", () => {
     // given - ultrabrain category requirement
     const ultrabrain = CATEGORY_MODEL_REQUIREMENTS["ultrabrain"]
 
     // when - accessing ultrabrain requirement
-    // then - fallbackChain exists with gpt-5.2-codex as first entry
+    // then - fallbackChain exists with gpt-5.3-codex as first entry
     expect(ultrabrain).toBeDefined()
     expect(ultrabrain.fallbackChain).toBeArray()
     expect(ultrabrain.fallbackChain.length).toBeGreaterThan(0)
 
     const primary = ultrabrain.fallbackChain[0]
     expect(primary.variant).toBe("xhigh")
-    expect(primary.model).toBe("gpt-5.2-codex")
+    expect(primary.model).toBe("gpt-5.3-codex")
     expect(primary.providers[0]).toBe("openai")
   })
 
-  test("deep has valid fallbackChain with gpt-5.2-codex as primary", () => {
+  test("deep has valid fallbackChain with gpt-5.3-codex as primary", () => {
     // given - deep category requirement
     const deep = CATEGORY_MODEL_REQUIREMENTS["deep"]
 
     // when - accessing deep requirement
-    // then - fallbackChain exists with gpt-5.2-codex as first entry, medium variant
+    // then - fallbackChain exists with gpt-5.3-codex as first entry, medium variant
     expect(deep).toBeDefined()
     expect(deep.fallbackChain).toBeArray()
     expect(deep.fallbackChain.length).toBeGreaterThan(0)
 
     const primary = deep.fallbackChain[0]
     expect(primary.variant).toBe("medium")
-    expect(primary.model).toBe("gpt-5.2-codex")
+    expect(primary.model).toBe("gpt-5.3-codex")
     expect(primary.providers[0]).toBe("openai")
   })
 
@@ -301,12 +301,12 @@ describe("CATEGORY_MODEL_REQUIREMENTS", () => {
     expect(primary.providers[0]).toBe("anthropic")
   })
 
-  test("unspecified-high has claude-opus-4-6 as primary before claude-opus-4-5", () => {
+  test("unspecified-high has claude-opus-4-6 as primary before claude-opus-4-6", () => {
     // #given - unspecified-high category requirement
     const unspecifiedHigh = CATEGORY_MODEL_REQUIREMENTS["unspecified-high"]
 
     // #when - accessing unspecified-high requirement
-    // #then - claude-opus-4-6 is first, claude-opus-4-5 is second
+    // #then - claude-opus-4-6 is first, claude-opus-4-6 is second
     expect(unspecifiedHigh).toBeDefined()
     expect(unspecifiedHigh.fallbackChain).toBeArray()
     expect(unspecifiedHigh.fallbackChain.length).toBeGreaterThan(1)
@@ -317,7 +317,7 @@ describe("CATEGORY_MODEL_REQUIREMENTS", () => {
     expect(primary.providers).toEqual(["anthropic"])
 
     const secondary = unspecifiedHigh.fallbackChain[1]
-    expect(secondary.model).toBe("claude-opus-4-5")
+    expect(secondary.model).toBe("claude-opus-4-6")
     expect(secondary.variant).toBe("max")
     expect(secondary.providers[0]).toBe("anthropic")
   })
@@ -392,14 +392,14 @@ describe("FallbackEntry type", () => {
     // given - a valid FallbackEntry object
     const entry: FallbackEntry = {
       providers: ["anthropic", "github-copilot", "opencode"],
-      model: "claude-opus-4-5",
+      model: "claude-opus-4-6",
       variant: "high",
     }
 
     // when - accessing properties
     // then - all properties are accessible
     expect(entry.providers).toEqual(["anthropic", "github-copilot", "opencode"])
-    expect(entry.model).toBe("claude-opus-4-5")
+    expect(entry.model).toBe("claude-opus-4-6")
     expect(entry.variant).toBe("high")
   })
 
@@ -421,7 +421,7 @@ describe("ModelRequirement type", () => {
     // given - a valid ModelRequirement object
     const requirement: ModelRequirement = {
       fallbackChain: [
-        { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-5", variant: "max" },
+        { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-6", variant: "max" },
         { providers: ["openai", "github-copilot"], model: "gpt-5.2", variant: "high" },
       ],
     }
@@ -430,7 +430,7 @@ describe("ModelRequirement type", () => {
     // then - fallbackChain is accessible with correct structure
     expect(requirement.fallbackChain).toBeArray()
     expect(requirement.fallbackChain).toHaveLength(2)
-    expect(requirement.fallbackChain[0].model).toBe("claude-opus-4-5")
+    expect(requirement.fallbackChain[0].model).toBe("claude-opus-4-6")
     expect(requirement.fallbackChain[1].model).toBe("gpt-5.2")
   })
 
@@ -480,12 +480,12 @@ describe("ModelRequirement type", () => {
 })
 
 describe("requiresModel field in categories", () => {
-  test("deep category has requiresModel set to gpt-5.2-codex", () => {
+  test("deep category has requiresModel set to gpt-5.3-codex", () => {
     // given
     const deep = CATEGORY_MODEL_REQUIREMENTS["deep"]
 
     // when / #then
-    expect(deep.requiresModel).toBe("gpt-5.2-codex")
+    expect(deep.requiresModel).toBe("gpt-5.3-codex")
   })
 
   test("artistry category has requiresModel set to gemini-3-pro", () => {
diff --git a/src/shared/model-requirements.ts b/src/shared/model-requirements.ts
index 709bec794..82a7c9ecb 100644
--- a/src/shared/model-requirements.ts
+++ b/src/shared/model-requirements.ts
@@ -16,7 +16,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
   sisyphus: {
     fallbackChain: [
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["kimi-for-coding"], model: "k2p5" },
       { providers: ["opencode"], model: "kimi-k2.5-free" },
       { providers: ["zai-coding-plan"], model: "glm-4.7" },
@@ -26,7 +26,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
   },
   hephaestus: {
     fallbackChain: [
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2-codex", variant: "medium" },
+      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.3-codex", variant: "medium" },
     ],
     requiresProvider: ["openai", "github-copilot", "opencode"],
   },
@@ -35,7 +35,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "high" },
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
     ],
   },
    librarian: {
@@ -66,7 +66,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
   prometheus: {
     fallbackChain: [
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["kimi-for-coding"], model: "k2p5" },
       { providers: ["opencode"], model: "kimi-k2.5-free" },
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
@@ -76,7 +76,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
   metis: {
     fallbackChain: [
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["kimi-for-coding"], model: "k2p5" },
       { providers: ["opencode"], model: "kimi-k2.5-free" },
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
@@ -87,7 +87,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
     fallbackChain: [
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "medium" },
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "high" },
     ],
   },
@@ -107,32 +107,32 @@ export const CATEGORY_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
     fallbackChain: [
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro" },
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["zai-coding-plan"], model: "glm-4.7" },
     ],
   },
   ultrabrain: {
     fallbackChain: [
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2-codex", variant: "xhigh" },
+      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.3-codex", variant: "xhigh" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "high" },
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
     ],
   },
   deep: {
     fallbackChain: [
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2-codex", variant: "medium" },
+      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.3-codex", variant: "medium" },
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "high" },
     ],
-    requiresModel: "gpt-5.2-codex",
+    requiresModel: "gpt-5.3-codex",
   },
   artistry: {
     fallbackChain: [
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro", variant: "high" },
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2" },
     ],
     requiresModel: "gemini-3-pro",
@@ -147,14 +147,14 @@ export const CATEGORY_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
   "unspecified-low": {
     fallbackChain: [
       { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-sonnet-4-5" },
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2-codex", variant: "medium" },
+      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.3-codex", variant: "medium" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-flash" },
     ],
   },
   "unspecified-high": {
     fallbackChain: [
       { providers: ["anthropic"], model: "claude-opus-4-6", variant: "max" },
-      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+      { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
       { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
       { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro" },
     ],
diff --git a/src/shared/model-resolver.test.ts b/src/shared/model-resolver.test.ts
index c08a1e9ec..340f55081 100644
--- a/src/shared/model-resolver.test.ts
+++ b/src/shared/model-resolver.test.ts
@@ -8,7 +8,7 @@ describe("resolveModel", () => {
     test("returns userModel when all three are set", () => {
       // given
       const input: ModelResolutionInput = {
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         inheritedModel: "openai/gpt-5.2",
         systemDefault: "google/gemini-3-pro",
       }
@@ -17,7 +17,7 @@ describe("resolveModel", () => {
       const result = resolveModel(input)
 
       // then
-      expect(result).toBe("anthropic/claude-opus-4-5")
+      expect(result).toBe("anthropic/claude-opus-4-6")
     })
 
     test("returns inheritedModel when userModel is undefined", () => {
@@ -87,7 +87,7 @@ describe("resolveModel", () => {
     test("same input returns same output (referential transparency)", () => {
       // given
       const input: ModelResolutionInput = {
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         inheritedModel: "openai/gpt-5.2",
         systemDefault: "google/gemini-3-pro",
       }
@@ -118,11 +118,11 @@ describe("resolveModelWithFallback", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         uiSelectedModel: "opencode/glm-4.7-free",
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         fallbackChain: [
-          { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-5" },
+          { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5", "github-copilot/claude-opus-4-5-preview"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6", "github-copilot/claude-opus-4-6-preview"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -139,8 +139,8 @@ describe("resolveModelWithFallback", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         uiSelectedModel: "opencode/glm-4.7-free",
-        userModel: "anthropic/claude-opus-4-5",
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        userModel: "anthropic/claude-opus-4-6",
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -156,8 +156,8 @@ describe("resolveModelWithFallback", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         uiSelectedModel: "   ",
-        userModel: "anthropic/claude-opus-4-5",
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        userModel: "anthropic/claude-opus-4-6",
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -165,16 +165,16 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
-      expect(logSpy).toHaveBeenCalledWith("Model resolved via config override", { model: "anthropic/claude-opus-4-5" })
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
+      expect(logSpy).toHaveBeenCalledWith("Model resolved via config override", { model: "anthropic/claude-opus-4-6" })
     })
 
     test("empty string uiSelectedModel falls through to config override", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         uiSelectedModel: "",
-        userModel: "anthropic/claude-opus-4-5",
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        userModel: "anthropic/claude-opus-4-6",
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -182,7 +182,7 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
     })
   })
 
@@ -190,11 +190,11 @@ describe("resolveModelWithFallback", () => {
     test("returns userModel with override source when userModel is provided", () => {
       // given
       const input: ExtendedModelResolutionInput = {
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         fallbackChain: [
-          { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-5" },
+          { providers: ["anthropic", "github-copilot"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5", "github-copilot/claude-opus-4-5-preview"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6", "github-copilot/claude-opus-4-6-preview"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -202,9 +202,9 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("override")
-      expect(logSpy).toHaveBeenCalledWith("Model resolved via config override", { model: "anthropic/claude-opus-4-5" })
+      expect(logSpy).toHaveBeenCalledWith("Model resolved via config override", { model: "anthropic/claude-opus-4-6" })
     })
 
     test("override takes priority even if model not in availableModels", () => {
@@ -212,9 +212,9 @@ describe("resolveModelWithFallback", () => {
       const input: ExtendedModelResolutionInput = {
         userModel: "custom/my-model",
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -231,9 +231,9 @@ describe("resolveModelWithFallback", () => {
       const input: ExtendedModelResolutionInput = {
         userModel: "   ",
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -249,9 +249,9 @@ describe("resolveModelWithFallback", () => {
       const input: ExtendedModelResolutionInput = {
         userModel: "",
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -268,9 +268,9 @@ describe("resolveModelWithFallback", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         fallbackChain: [
-          { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5" },
+          { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["github-copilot/claude-opus-4-5-preview", "opencode/claude-opus-4-7"]),
+        availableModels: new Set(["github-copilot/claude-opus-4-6-preview", "opencode/claude-opus-4-7"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -278,12 +278,12 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then
-      expect(result!.model).toBe("github-copilot/claude-opus-4-5-preview")
+      expect(result!.model).toBe("github-copilot/claude-opus-4-6-preview")
       expect(result!.source).toBe("provider-fallback")
       expect(logSpy).toHaveBeenCalledWith("Model resolved via fallback chain (availability confirmed)", {
         provider: "github-copilot",
-        model: "claude-opus-4-5",
-        match: "github-copilot/claude-opus-4-5-preview",
+        model: "claude-opus-4-6",
+        match: "github-copilot/claude-opus-4-6-preview",
         variant: undefined,
       })
     })
@@ -294,7 +294,7 @@ describe("resolveModelWithFallback", () => {
         fallbackChain: [
           { providers: ["openai", "anthropic", "google"], model: "gpt-5.2" },
         ],
-        availableModels: new Set(["openai/gpt-5.2", "anthropic/claude-opus-4-5", "google/gemini-3-pro"]),
+        availableModels: new Set(["openai/gpt-5.2", "anthropic/claude-opus-4-6", "google/gemini-3-pro"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -330,7 +330,7 @@ describe("resolveModelWithFallback", () => {
         fallbackChain: [
           { providers: ["anthropic", "github-copilot"], model: "claude-opus" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5", "github-copilot/claude-opus-4-5-preview"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6", "github-copilot/claude-opus-4-6-preview"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -338,14 +338,14 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("provider-fallback")
     })
 
     test("skips fallback chain when not provided", () => {
       // given
       const input: ExtendedModelResolutionInput = {
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -360,7 +360,7 @@ describe("resolveModelWithFallback", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         fallbackChain: [],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -377,7 +377,7 @@ describe("resolveModelWithFallback", () => {
         fallbackChain: [
           { providers: ["anthropic"], model: "CLAUDE-OPUS" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -385,7 +385,7 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("provider-fallback")
     })
 
@@ -476,7 +476,7 @@ describe("resolveModelWithFallback", () => {
         fallbackChain: [
           { providers: ["anthropic"], model: "nonexistent-model" },
         ],
-        availableModels: new Set(["openai/gpt-5.2", "anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["openai/gpt-5.2", "anthropic/claude-opus-4-6"]),
         systemDefaultModel: "google/gemini-3-pro",
       }
 
@@ -494,7 +494,7 @@ describe("resolveModelWithFallback", () => {
       const cacheSpy = spyOn(connectedProvidersCache, "readConnectedProvidersCache").mockReturnValue(null)
       const input: ExtendedModelResolutionInput = {
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
         availableModels: new Set(),
         systemDefaultModel: undefined, // no system default configured
@@ -513,7 +513,7 @@ describe("resolveModelWithFallback", () => {
       const cacheSpy = spyOn(connectedProvidersCache, "readConnectedProvidersCache").mockReturnValue(["openai", "google"])
       const input: ExtendedModelResolutionInput = {
         fallbackChain: [
-          { providers: ["anthropic", "openai"], model: "claude-opus-4-5" },
+          { providers: ["anthropic", "openai"], model: "claude-opus-4-6" },
         ],
         availableModels: new Set(),
         systemDefaultModel: "google/gemini-3-pro",
@@ -523,7 +523,7 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then - should use connected provider (openai) from fallback chain
-      expect(result!.model).toBe("openai/claude-opus-4-5")
+      expect(result!.model).toBe("openai/claude-opus-4-6")
       expect(result!.source).toBe("provider-fallback")
       cacheSpy.mockRestore()
     })
@@ -556,14 +556,14 @@ describe("resolveModelWithFallback", () => {
           { providers: ["anthropic", "opencode"], model: "claude-haiku-4-5" },
         ],
         availableModels: new Set(),
-        systemDefaultModel: "quotio/claude-opus-4-5-20251101",
+        systemDefaultModel: "quotio/claude-opus-4-6-20251101",
       }
 
       // when
       const result = resolveModelWithFallback(input)
 
       // then - no provider in fallback is connected, fall through to system default
-      expect(result!.model).toBe("quotio/claude-opus-4-5-20251101")
+      expect(result!.model).toBe("quotio/claude-opus-4-6-20251101")
       expect(result!.source).toBe("system-default")
       cacheSpy.mockRestore()
     })
@@ -573,7 +573,7 @@ describe("resolveModelWithFallback", () => {
       const cacheSpy = spyOn(connectedProvidersCache, "readConnectedProvidersCache").mockReturnValue(null)
       const input: ExtendedModelResolutionInput = {
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
         availableModels: new Set(),
         systemDefaultModel: "google/gemini-3-pro",
@@ -607,20 +607,20 @@ describe("resolveModelWithFallback", () => {
   describe("Multi-entry fallbackChain", () => {
     test("resolves to claude-opus when OpenAI unavailable but Anthropic available (oracle scenario)", () => {
       // given
-      const availableModels = new Set(["anthropic/claude-opus-4-5"])
+      const availableModels = new Set(["anthropic/claude-opus-4-6"])
 
       // when
       const result = resolveModelWithFallback({
         fallbackChain: [
           { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
-          { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-5", variant: "max" },
+          { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-opus-4-6", variant: "max" },
         ],
         availableModels,
         systemDefaultModel: "system/default",
       })
 
       // then
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("provider-fallback")
     })
 
@@ -647,14 +647,14 @@ describe("resolveModelWithFallback", () => {
       // given
       const availableModels = new Set([
         "openai/gpt-5.2",
-        "anthropic/claude-opus-4-5",
+        "anthropic/claude-opus-4-6",
       ])
 
       // when
       const result = resolveModelWithFallback({
         fallbackChain: [
           { providers: ["openai"], model: "gpt-5.2" },
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
         availableModels,
         systemDefaultModel: "system/default",
@@ -673,7 +673,7 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback({
         fallbackChain: [
           { providers: ["openai"], model: "gpt-5.2" },
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
           { providers: ["google"], model: "gemini-3-pro" },
         ],
         availableModels,
@@ -690,7 +690,7 @@ describe("resolveModelWithFallback", () => {
     test("result has correct ModelResolutionResult shape", () => {
       // given
       const input: ExtendedModelResolutionInput = {
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         availableModels: new Set(),
         systemDefaultModel: "google/gemini-3-pro",
       }
@@ -713,7 +713,7 @@ describe("resolveModelWithFallback", () => {
         fallbackChain: [
           { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro" },
         ],
-        availableModels: new Set(["google/gemini-3-pro-preview", "anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["google/gemini-3-pro-preview", "anthropic/claude-opus-4-6"]),
         systemDefaultModel: "anthropic/claude-sonnet-4-5",
       }
 
@@ -749,9 +749,9 @@ describe("resolveModelWithFallback", () => {
       const input: ExtendedModelResolutionInput = {
         categoryDefaultModel: "google/gemini-3-pro",
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: "system/default",
       }
 
@@ -759,19 +759,19 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then - should fall through to fallbackChain
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("provider-fallback")
     })
 
     test("userModel takes priority over categoryDefaultModel", () => {
       // given - both userModel and categoryDefaultModel provided
       const input: ExtendedModelResolutionInput = {
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         categoryDefaultModel: "google/gemini-3-pro",
         fallbackChain: [
           { providers: ["google"], model: "gemini-3-pro" },
         ],
-        availableModels: new Set(["google/gemini-3-pro-preview", "anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["google/gemini-3-pro-preview", "anthropic/claude-opus-4-6"]),
         systemDefaultModel: "system/default",
       }
 
@@ -779,7 +779,7 @@ describe("resolveModelWithFallback", () => {
       const result = resolveModelWithFallback(input)
 
       // then - userModel wins
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("override")
     })
 
@@ -837,7 +837,7 @@ describe("resolveModelWithFallback", () => {
     test("still returns override when userModel provided even if systemDefaultModel undefined", () => {
       // given
       const input: ExtendedModelResolutionInput = {
-        userModel: "anthropic/claude-opus-4-5",
+        userModel: "anthropic/claude-opus-4-6",
         availableModels: new Set(),
         systemDefaultModel: undefined,
       }
@@ -847,7 +847,7 @@ describe("resolveModelWithFallback", () => {
 
       // then
       expect(result).toBeDefined()
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("override")
     })
 
@@ -855,9 +855,9 @@ describe("resolveModelWithFallback", () => {
       // given
       const input: ExtendedModelResolutionInput = {
         fallbackChain: [
-          { providers: ["anthropic"], model: "claude-opus-4-5" },
+          { providers: ["anthropic"], model: "claude-opus-4-6" },
         ],
-        availableModels: new Set(["anthropic/claude-opus-4-5"]),
+        availableModels: new Set(["anthropic/claude-opus-4-6"]),
         systemDefaultModel: undefined,
       }
 
@@ -866,7 +866,7 @@ describe("resolveModelWithFallback", () => {
 
       // then
       expect(result).toBeDefined()
-      expect(result!.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.model).toBe("anthropic/claude-opus-4-6")
       expect(result!.source).toBe("provider-fallback")
     })
   })
diff --git a/src/tools/delegate-task/constants.ts b/src/tools/delegate-task/constants.ts
index ce0645736..ea405faef 100644
--- a/src/tools/delegate-task/constants.ts
+++ b/src/tools/delegate-task/constants.ts
@@ -194,12 +194,12 @@ You are NOT an interactive assistant. You are an autonomous problem-solver.
 
 export const DEFAULT_CATEGORIES: Record<string, CategoryConfig> = {
   "visual-engineering": { model: "google/gemini-3-pro" },
-  ultrabrain: { model: "openai/gpt-5.2-codex", variant: "xhigh" },
-  deep: { model: "openai/gpt-5.2-codex", variant: "medium" },
+  ultrabrain: { model: "openai/gpt-5.3-codex", variant: "xhigh" },
+  deep: { model: "openai/gpt-5.3-codex", variant: "medium" },
   artistry: { model: "google/gemini-3-pro", variant: "high" },
   quick: { model: "anthropic/claude-haiku-4-5" },
   "unspecified-low": { model: "anthropic/claude-sonnet-4-5" },
-  "unspecified-high": { model: "anthropic/claude-opus-4-5", variant: "max" },
+  "unspecified-high": { model: "anthropic/claude-opus-4-6", variant: "max" },
   writing: { model: "google/gemini-3-flash" },
 }
 
@@ -343,11 +343,11 @@ FOR EVERY TASK, YOU MUST RECOMMEND:
 | Category | Best For | Model |
 |----------|----------|-------|
 | \`visual-engineering\` | Frontend, UI/UX, design, styling, animation | google/gemini-3-pro |
-| \`ultrabrain\` | Complex architecture, deep logical reasoning | openai/gpt-5.2-codex |
+| \`ultrabrain\` | Complex architecture, deep logical reasoning | openai/gpt-5.3-codex |
 | \`artistry\` | Highly creative/artistic tasks, novel ideas | google/gemini-3-pro |
 | \`quick\` | Trivial tasks - single file, typo fixes | anthropic/claude-haiku-4-5 |
 | \`unspecified-low\` | Moderate effort, doesn't fit other categories | anthropic/claude-sonnet-4-5 |
-| \`unspecified-high\` | High effort, doesn't fit other categories | anthropic/claude-opus-4-5 |
+| \`unspecified-high\` | High effort, doesn't fit other categories | anthropic/claude-opus-4-6 |
 | \`writing\` | Documentation, prose, technical writing | google/gemini-3-flash |
 
 ### AVAILABLE SKILLS (ALWAYS EVALUATE ALL)
diff --git a/src/tools/delegate-task/tools.test.ts b/src/tools/delegate-task/tools.test.ts
index 84ee612b5..effc0bf40 100644
--- a/src/tools/delegate-task/tools.test.ts
+++ b/src/tools/delegate-task/tools.test.ts
@@ -28,9 +28,9 @@ describe("sisyphus-task", () => {
     cacheSpy = spyOn(connectedProvidersCache, "readConnectedProvidersCache").mockReturnValue(["anthropic", "google", "openai"])
     providerModelsSpy = spyOn(connectedProvidersCache, "readProviderModelsCache").mockReturnValue({
       models: {
-        anthropic: ["claude-opus-4-5", "claude-sonnet-4-5", "claude-haiku-4-5"],
+        anthropic: ["claude-opus-4-6", "claude-sonnet-4-5", "claude-haiku-4-5"],
         google: ["gemini-3-pro", "gemini-3-flash"],
-        openai: ["gpt-5.2", "gpt-5.2-codex"],
+        openai: ["gpt-5.2", "gpt-5.3-codex"],
       },
       connected: ["anthropic", "google", "openai"],
       updatedAt: "2026-01-01T00:00:00.000Z",
@@ -59,7 +59,7 @@ describe("sisyphus-task", () => {
 
       // when / #then
       expect(category).toBeDefined()
-      expect(category.model).toBe("openai/gpt-5.2-codex")
+      expect(category.model).toBe("openai/gpt-5.3-codex")
       expect(category.variant).toBe("xhigh")
     })
 
@@ -69,7 +69,7 @@ describe("sisyphus-task", () => {
 
       // when / #then
       expect(category).toBeDefined()
-      expect(category.model).toBe("openai/gpt-5.2-codex")
+      expect(category.model).toBe("openai/gpt-5.3-codex")
       expect(category.variant).toBe("medium")
     })
   })
@@ -216,7 +216,7 @@ describe("sisyphus-task", () => {
         app: { agents: async () => ({ data: [] }) },
         config: { get: async () => ({}) }, // No model configured
         provider: { list: async () => ({ data: { connected: ["openai"] } }) },
-        model: { list: async () => ({ data: [{ provider: "openai", id: "gpt-5.2-codex" }] }) },
+        model: { list: async () => ({ data: [{ provider: "openai", id: "gpt-5.3-codex" }] }) },
         session: {
           create: async () => ({ data: { id: "test-session" } }),
           prompt: async () => ({ data: {} }),
@@ -319,7 +319,7 @@ describe("sisyphus-task", () => {
     test("blocks requiresModel when availability is known and missing the required model", () => {
       // given
       const categoryName = "deep"
-      const availableModels = new Set<string>(["anthropic/claude-opus-4-5"])
+      const availableModels = new Set<string>(["anthropic/claude-opus-4-6"])
 
       // when
       const result = resolveCategoryConfig(categoryName, {
@@ -349,9 +349,9 @@ describe("sisyphus-task", () => {
     test("bypasses requiresModel when explicit user config provided", () => {
       // #given
       const categoryName = "deep"
-      const availableModels = new Set<string>(["anthropic/claude-opus-4-5"])
+      const availableModels = new Set<string>(["anthropic/claude-opus-4-6"])
       const userCategories = {
-        deep: { model: "anthropic/claude-opus-4-5" },
+        deep: { model: "anthropic/claude-opus-4-6" },
       }
 
       // #when
@@ -363,7 +363,7 @@ describe("sisyphus-task", () => {
 
       // #then
       expect(result).not.toBeNull()
-      expect(result!.config.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.config.model).toBe("anthropic/claude-opus-4-6")
     })
 
     test("bypasses requiresModel when explicit user config provided even with empty availability", () => {
@@ -371,7 +371,7 @@ describe("sisyphus-task", () => {
       const categoryName = "deep"
       const availableModels = new Set<string>()
       const userCategories = {
-        deep: { model: "anthropic/claude-opus-4-5" },
+        deep: { model: "anthropic/claude-opus-4-6" },
       }
 
       // #when
@@ -383,7 +383,7 @@ describe("sisyphus-task", () => {
 
       // #then
       expect(result).not.toBeNull()
-      expect(result!.config.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.config.model).toBe("anthropic/claude-opus-4-6")
     })
 
     test("returns default model from DEFAULT_CATEGORIES for builtin category", () => {
@@ -403,7 +403,7 @@ describe("sisyphus-task", () => {
       // given
       const categoryName = "visual-engineering"
       const userCategories = {
-        "visual-engineering": { model: "anthropic/claude-opus-4-5" },
+        "visual-engineering": { model: "anthropic/claude-opus-4-6" },
       }
 
       // when
@@ -411,7 +411,7 @@ describe("sisyphus-task", () => {
 
       // then
       expect(result).not.toBeNull()
-      expect(result!.config.model).toBe("anthropic/claude-opus-4-5")
+      expect(result!.config.model).toBe("anthropic/claude-opus-4-6")
     })
 
     test("user prompt_append is appended to default", () => {
@@ -475,7 +475,7 @@ describe("sisyphus-task", () => {
     test("category built-in model takes precedence over inheritedModel", () => {
       // given - builtin category with its own model, parent model also provided
       const categoryName = "visual-engineering"
-      const inheritedModel = "cliproxy/claude-opus-4-5"
+      const inheritedModel = "cliproxy/claude-opus-4-6"
 
       // when
       const result = resolveCategoryConfig(categoryName, { inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
@@ -489,7 +489,7 @@ describe("sisyphus-task", () => {
       // given - custom category with no model defined
       const categoryName = "my-custom-no-model"
       const userCategories = { "my-custom-no-model": { temperature: 0.5 } } as unknown as Record<string, CategoryConfig>
-      const inheritedModel = "cliproxy/claude-opus-4-5"
+      const inheritedModel = "cliproxy/claude-opus-4-6"
 
       // when
       const result = resolveCategoryConfig(categoryName, { userCategories, inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
@@ -505,7 +505,7 @@ describe("sisyphus-task", () => {
       const userCategories = {
         "visual-engineering": { model: "my-provider/my-model" },
       }
-      const inheritedModel = "cliproxy/claude-opus-4-5"
+      const inheritedModel = "cliproxy/claude-opus-4-6"
 
       // when
       const result = resolveCategoryConfig(categoryName, { userCategories, inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
@@ -613,7 +613,7 @@ describe("sisyphus-task", () => {
       const mockClient = {
         app: { agents: async () => ({ data: [] }) },
         config: { get: async () => ({ data: { model: SYSTEM_DEFAULT_MODEL } }) },
-        model: { list: async () => [{ provider: "anthropic", id: "claude-opus-4-5" }] },
+        model: { list: async () => [{ provider: "anthropic", id: "claude-opus-4-6" }] },
         session: {
           create: async () => ({ data: { id: "test-session" } }),
           prompt: async () => ({ data: {} }),
@@ -649,7 +649,7 @@ describe("sisyphus-task", () => {
       // then - variant MUST be "max" from DEFAULT_CATEGORIES
       expect(launchInput.model).toEqual({
         providerID: "anthropic",
-        modelID: "claude-opus-4-5",
+        modelID: "claude-opus-4-6",
         variant: "max",
       })
     })
@@ -664,7 +664,7 @@ describe("sisyphus-task", () => {
       const mockClient = {
         app: { agents: async () => ({ data: [] }) },
         config: { get: async () => ({ data: { model: SYSTEM_DEFAULT_MODEL } }) },
-        model: { list: async () => [{ provider: "anthropic", id: "claude-opus-4-5" }] },
+        model: { list: async () => [{ provider: "anthropic", id: "claude-opus-4-6" }] },
         session: {
           get: async () => ({ data: { directory: "/project" } }),
           create: async () => ({ data: { id: "ses_sync_default_variant" } }),
@@ -707,7 +707,7 @@ describe("sisyphus-task", () => {
       // then - variant MUST be "max" from DEFAULT_CATEGORIES (passed as separate field)
       expect(promptBody.model).toEqual({
         providerID: "anthropic",
-        modelID: "claude-opus-4-5",
+        modelID: "claude-opus-4-6",
       })
       expect(promptBody.variant).toBe("max")
     }, { timeout: 20000 })
@@ -1754,7 +1754,7 @@ describe("sisyphus-task", () => {
         abort: new AbortController().signal,
       }
 
-      // when - using ultrabrain category (default model is openai/gpt-5.2-codex)
+      // when - using ultrabrain category (default model is openai/gpt-5.3-codex)
       await tool.execute(
         {
           description: "Override precedence test",
@@ -1805,7 +1805,7 @@ describe("sisyphus-task", () => {
         client: mockClient,
         sisyphusJuniorModel: "anthropic/claude-sonnet-4-5",
         userCategories: {
-          ultrabrain: { model: "openai/gpt-5.2-codex" },
+          ultrabrain: { model: "openai/gpt-5.3-codex" },
         },
       })
 
@@ -1830,7 +1830,7 @@ describe("sisyphus-task", () => {
 
       // then - explicit category model should win
       expect(launchInput.model.providerID).toBe("openai")
-      expect(launchInput.model.modelID).toBe("gpt-5.2-codex")
+      expect(launchInput.model.modelID).toBe("gpt-5.3-codex")
     })
   })
 
@@ -2083,7 +2083,7 @@ describe("sisyphus-task", () => {
       
       // then - catalog model is used
       expect(resolved).not.toBeNull()
-      expect(resolved!.config.model).toBe("openai/gpt-5.2-codex")
+      expect(resolved!.config.model).toBe("openai/gpt-5.3-codex")
       expect(resolved!.config.variant).toBe("xhigh")
     })
 
@@ -2102,22 +2102,22 @@ describe("sisyphus-task", () => {
     test("category built-in model takes precedence over inheritedModel for builtin category", () => {
       // given - builtin ultrabrain category with its own model, inherited model also provided
       const categoryName = "ultrabrain"
-      const inheritedModel = "cliproxy/claude-opus-4-5"
+      const inheritedModel = "cliproxy/claude-opus-4-6"
       
       // when
       const resolved = resolveCategoryConfig(categoryName, { inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
       
-      // then - category's built-in model wins (ultrabrain uses gpt-5.2-codex)
+      // then - category's built-in model wins (ultrabrain uses gpt-5.3-codex)
       expect(resolved).not.toBeNull()
       const actualModel = resolved!.config.model
-      expect(actualModel).toBe("openai/gpt-5.2-codex")
+      expect(actualModel).toBe("openai/gpt-5.3-codex")
     })
 
     test("when user defines model - modelInfo should report user-defined regardless of inheritedModel", () => {
       // given
       const categoryName = "ultrabrain"
       const userCategories = { "ultrabrain": { model: "my-provider/custom-model" } }
-      const inheritedModel = "cliproxy/claude-opus-4-5"
+      const inheritedModel = "cliproxy/claude-opus-4-6"
       
       // when
       const resolved = resolveCategoryConfig(categoryName, { userCategories, inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
@@ -2134,7 +2134,7 @@ describe("sisyphus-task", () => {
       // given - This test verifies the fix for PR #770 bug
       // The bug was: checking `if (inheritedModel)` instead of `if (actualModel === inheritedModel)`
       const categoryName = "ultrabrain"
-      const inheritedModel = "cliproxy/claude-opus-4-5"
+      const inheritedModel = "cliproxy/claude-opus-4-6"
       const userCategories = { "ultrabrain": { model: "user/model" } }
       
       // when - user model wins
@@ -2162,14 +2162,14 @@ describe("sisyphus-task", () => {
       // given a builtin category with its own model, and an inherited model from parent
       // The CORRECT chain: userConfig?.model ?? categoryBuiltIn ?? systemDefaultModel
       const categoryName = "ultrabrain"
-      const inheritedModel = "anthropic/claude-opus-4-5"
+      const inheritedModel = "anthropic/claude-opus-4-6"
       
-      // when category has a built-in model (gpt-5.2-codex for ultrabrain)
+      // when category has a built-in model (gpt-5.3-codex for ultrabrain)
       const resolved = resolveCategoryConfig(categoryName, { inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
       
       // then category's built-in model should be used, NOT inheritedModel
       expect(resolved).not.toBeNull()
-      expect(resolved!.model).toBe("openai/gpt-5.2-codex")
+      expect(resolved!.model).toBe("openai/gpt-5.3-codex")
     })
 
     test("FIXED: systemDefaultModel is used when no userConfig.model and no inheritedModel", () => {
@@ -2193,7 +2193,7 @@ describe("sisyphus-task", () => {
       // given userConfig.model is explicitly set
       const categoryName = "ultrabrain"
       const userCategories = { "ultrabrain": { model: "custom/user-model" } }
-      const inheritedModel = "anthropic/claude-opus-4-5"
+      const inheritedModel = "anthropic/claude-opus-4-6"
       const systemDefaultModel = "anthropic/claude-sonnet-4-5"
       
       // when resolveCategoryConfig is called with all sources
@@ -2212,7 +2212,7 @@ describe("sisyphus-task", () => {
       // given userConfig.model is empty string "" for a custom category (no built-in model)
       const categoryName = "custom-empty-model"
       const userCategories = { "custom-empty-model": { model: "", temperature: 0.3 } }
-      const inheritedModel = "anthropic/claude-opus-4-5"
+      const inheritedModel = "anthropic/claude-opus-4-6"
       
       // when resolveCategoryConfig is called
       const resolved = resolveCategoryConfig(categoryName, { userCategories, inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
@@ -2227,7 +2227,7 @@ describe("sisyphus-task", () => {
       const categoryName = "visual-engineering"
       // Using type assertion since we're testing fallback behavior for categories without model
       const userCategories = { "visual-engineering": { temperature: 0.2 } } as unknown as Record<string, CategoryConfig>
-      const inheritedModel = "anthropic/claude-opus-4-5"
+      const inheritedModel = "anthropic/claude-opus-4-6"
       
       // when resolveCategoryConfig is called
       const resolved = resolveCategoryConfig(categoryName, { userCategories, inheritedModel, systemDefaultModel: SYSTEM_DEFAULT_MODEL })
@@ -2472,7 +2472,7 @@ describe("sisyphus-task", () => {
         app: {
           agents: async () => ({
             data: [
-              { name: "oracle", mode: "subagent", model: { providerID: "anthropic", modelID: "claude-opus-4-5" } },
+              { name: "oracle", mode: "subagent", model: { providerID: "anthropic", modelID: "claude-opus-4-6" } },
             ],
           }),
         },
@@ -2518,7 +2518,7 @@ describe("sisyphus-task", () => {
       // then - matched agent's model should be passed to session.prompt
       expect(promptBody.model).toEqual({
         providerID: "anthropic",
-        modelID: "claude-opus-4-5",
+        modelID: "claude-opus-4-6",
       })
     }, { timeout: 20000 })