diff --git a/src/cli/__snapshots__/model-fallback.test.ts.snap b/src/cli/__snapshots__/model-fallback.test.ts.snap
index b9269547a..ca060a57c 100644
--- a/src/cli/__snapshots__/model-fallback.test.ts.snap
+++ b/src/cli/__snapshots__/model-fallback.test.ts.snap
@@ -191,7 +191,8 @@ exports[`generateModelConfig single native provider uses OpenAI models when only
   "$schema": "https://raw.githubusercontent.com/code-yeongyu/oh-my-opencode/dev/assets/oh-my-opencode.schema.json",
   "agents": {
     "atlas": {
-      "model": "openai/gpt-5.2",
+      "model": "openai/gpt-5.4",
+      "variant": "medium",
     },
     "explore": {
       "model": "opencode/gpt-5-nano",
@@ -208,8 +209,8 @@ exports[`generateModelConfig single native provider uses OpenAI models when only
       "variant": "high",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
@@ -220,7 +221,7 @@ exports[`generateModelConfig single native provider uses OpenAI models when only
       "variant": "high",
     },
     "prometheus": {
-      "model": "openai/gpt-5.2",
+      "model": "openai/gpt-5.4",
       "variant": "high",
     },
   },
@@ -259,7 +260,8 @@ exports[`generateModelConfig single native provider uses OpenAI models with isMa
   "$schema": "https://raw.githubusercontent.com/code-yeongyu/oh-my-opencode/dev/assets/oh-my-opencode.schema.json",
   "agents": {
     "atlas": {
-      "model": "openai/gpt-5.2",
+      "model": "openai/gpt-5.4",
+      "variant": "medium",
     },
     "explore": {
       "model": "opencode/gpt-5-nano",
@@ -276,8 +278,8 @@ exports[`generateModelConfig single native provider uses OpenAI models with isMa
       "variant": "high",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
@@ -288,7 +290,7 @@ exports[`generateModelConfig single native provider uses OpenAI models with isMa
       "variant": "high",
     },
     "prometheus": {
-      "model": "openai/gpt-5.2",
+      "model": "openai/gpt-5.4",
       "variant": "high",
     },
   },
@@ -466,8 +468,8 @@ exports[`generateModelConfig all native providers uses preferred models from fal
       "variant": "max",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
@@ -541,8 +543,8 @@ exports[`generateModelConfig all native providers uses preferred models with isM
       "variant": "max",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
@@ -617,8 +619,8 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models when on
       "variant": "max",
     },
     "momus": {
-      "model": "opencode/gpt-5.2",
-      "variant": "medium",
+      "model": "opencode/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "opencode/gpt-5.3-codex",
@@ -692,8 +694,8 @@ exports[`generateModelConfig fallback providers uses OpenCode Zen models with is
       "variant": "max",
     },
     "momus": {
-      "model": "opencode/gpt-5.2",
-      "variant": "medium",
+      "model": "opencode/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "opencode/gpt-5.3-codex",
@@ -764,8 +766,8 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models when
       "variant": "max",
     },
     "momus": {
-      "model": "github-copilot/gpt-5.2",
-      "variant": "medium",
+      "model": "github-copilot/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "github-copilot/gemini-3-flash-preview",
@@ -830,8 +832,8 @@ exports[`generateModelConfig fallback providers uses GitHub Copilot models with
       "variant": "max",
     },
     "momus": {
-      "model": "github-copilot/gpt-5.2",
-      "variant": "medium",
+      "model": "github-copilot/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "github-copilot/gemini-3-flash-preview",
@@ -908,7 +910,7 @@ exports[`generateModelConfig fallback providers uses ZAI model for librarian whe
       "model": "opencode/glm-4.7-free",
     },
     "sisyphus": {
-      "model": "zai-coding-plan/glm-4.7",
+      "model": "zai-coding-plan/glm-5",
     },
   },
   "categories": {
@@ -963,7 +965,7 @@ exports[`generateModelConfig fallback providers uses ZAI model for librarian wit
       "model": "opencode/glm-4.7-free",
     },
     "sisyphus": {
-      "model": "zai-coding-plan/glm-4.7",
+      "model": "zai-coding-plan/glm-5",
     },
   },
   "categories": {
@@ -1011,8 +1013,8 @@ exports[`generateModelConfig mixed provider scenarios uses Claude + OpenCode Zen
       "variant": "max",
     },
     "momus": {
-      "model": "opencode/gpt-5.2",
-      "variant": "medium",
+      "model": "opencode/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "opencode/gpt-5.3-codex",
@@ -1086,8 +1088,8 @@ exports[`generateModelConfig mixed provider scenarios uses OpenAI + Copilot comb
       "variant": "max",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
@@ -1288,8 +1290,8 @@ exports[`generateModelConfig mixed provider scenarios uses all fallback provider
       "variant": "max",
     },
     "momus": {
-      "model": "github-copilot/gpt-5.2",
-      "variant": "medium",
+      "model": "github-copilot/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "opencode/gpt-5.3-codex",
@@ -1363,8 +1365,8 @@ exports[`generateModelConfig mixed provider scenarios uses all providers togethe
       "variant": "max",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
@@ -1438,8 +1440,8 @@ exports[`generateModelConfig mixed provider scenarios uses all providers with is
       "variant": "max",
     },
     "momus": {
-      "model": "openai/gpt-5.2",
-      "variant": "medium",
+      "model": "openai/gpt-5.4",
+      "variant": "xhigh",
     },
     "multimodal-looker": {
       "model": "openai/gpt-5.3-codex",
diff --git a/src/cli/model-fallback-requirements.ts b/src/cli/model-fallback-requirements.ts
index 6fd0a5c3f..815ff9f01 100644
--- a/src/cli/model-fallback-requirements.ts
+++ b/src/cli/model-fallback-requirements.ts
@@ -13,8 +13,7 @@ export const CLI_AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
         variant: "max",
       },
       { providers: ["kimi-for-coding"], model: "k2p5" },
-      { providers: ["zai-coding-plan"], model: "glm-4.7" },
-      { providers: ["opencode"], model: "glm-4.7-free" },
+      { providers: ["zai-coding-plan", "opencode"], model: "glm-5" },
     ],
     requiresAnyModel: true,
   },
@@ -90,7 +89,7 @@ export const CLI_AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
       { providers: ["kimi-for-coding"], model: "k2p5" },
       {
         providers: ["openai", "github-copilot", "opencode"],
-        model: "gpt-5.2",
+        model: "gpt-5.4",
         variant: "high",
       },
       {
@@ -123,8 +122,8 @@ export const CLI_AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
     fallbackChain: [
       {
         providers: ["openai", "github-copilot", "opencode"],
-        model: "gpt-5.2",
-        variant: "medium",
+        model: "gpt-5.4",
+        variant: "xhigh",
       },
       {
         providers: ["anthropic", "github-copilot", "opencode"],
@@ -145,7 +144,7 @@ export const CLI_AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
         providers: ["anthropic", "github-copilot", "opencode"],
         model: "claude-sonnet-4-5",
       },
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2" },
+      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.4", variant: "medium" },
       {
         providers: ["google", "github-copilot", "opencode"],
         model: "gemini-3.1-pro",
diff --git a/src/shared/model-requirements.test.ts b/src/shared/model-requirements.test.ts
index be301947f..46b2b056e 100644
--- a/src/shared/model-requirements.test.ts
+++ b/src/shared/model-requirements.test.ts
@@ -145,19 +145,19 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
     expect(primary.variant).toBe("max")
   })
 
-  test("momus has valid fallbackChain with gpt-5.2 as primary", () => {
+  test("momus has valid fallbackChain with gpt-5.4 as primary", () => {
     // given - momus agent requirement
     const momus = AGENT_MODEL_REQUIREMENTS["momus"]
 
     // when - accessing Momus requirement
-    // then - fallbackChain exists with gpt-5.2 as first entry, variant medium
+    // then - fallbackChain exists with gpt-5.4 as first entry, variant xhigh
     expect(momus).toBeDefined()
     expect(momus.fallbackChain).toBeArray()
     expect(momus.fallbackChain.length).toBeGreaterThan(0)
 
     const primary = momus.fallbackChain[0]
-    expect(primary.model).toBe("gpt-5.2")
-    expect(primary.variant).toBe("medium")
+    expect(primary.model).toBe("gpt-5.4")
+    expect(primary.variant).toBe("xhigh")
     expect(primary.providers[0]).toBe("openai")
   })
 
@@ -174,6 +174,10 @@ describe("AGENT_MODEL_REQUIREMENTS", () => {
     const primary = atlas.fallbackChain[0]
     expect(primary.model).toBe("claude-sonnet-4-6")
     expect(primary.providers[0]).toBe("anthropic")
+
+    const secondary = atlas.fallbackChain[1]
+    expect(secondary.model).toBe("gpt-5.4")
+    expect(secondary.variant).toBe("medium")
   })
 
   test("hephaestus supports openai, github-copilot, venice, and opencode providers", () => {
diff --git a/src/shared/model-requirements.ts b/src/shared/model-requirements.ts
index f656f52d4..9f444f5a3 100644
--- a/src/shared/model-requirements.ts
+++ b/src/shared/model-requirements.ts
@@ -101,7 +101,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
       },
       {
         providers: ["openai", "github-copilot", "opencode"],
-        model: "gpt-5.2",
+        model: "gpt-5.4",
         variant: "high",
       },
       {
@@ -133,8 +133,8 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
     fallbackChain: [
       {
         providers: ["openai", "github-copilot", "opencode"],
-        model: "gpt-5.2",
-        variant: "medium",
+        model: "gpt-5.4",
+        variant: "xhigh",
       },
       {
         providers: ["anthropic", "github-copilot", "opencode"],
@@ -154,7 +154,7 @@ export const AGENT_MODEL_REQUIREMENTS: Record<string, ModelRequirement> = {
         providers: ["anthropic", "github-copilot", "opencode"],
         model: "claude-sonnet-4-6",
       },
-      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2" },
+      { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.4", variant: "medium" },
     ],
   },
 };