diff --git a/src/cli/model-fallback.test.ts b/src/cli/model-fallback.test.ts
new file mode 100644
index 000000000..61e1ad7d7
--- /dev/null
+++ b/src/cli/model-fallback.test.ts
@@ -0,0 +1,423 @@
+import { describe, expect, test } from "bun:test"
+
+import { generateModelConfig } from "./model-fallback"
+import type { InstallConfig } from "./types"
+
+function createConfig(overrides: Partial<InstallConfig> = {}): InstallConfig {
+  return {
+    hasClaude: false,
+    isMax20: false,
+    hasOpenAI: false,
+    hasGemini: false,
+    hasCopilot: false,
+    hasOpencodeZen: false,
+    hasZaiCodingPlan: false,
+    ...overrides,
+  }
+}
+
+describe("generateModelConfig", () => {
+  describe("no providers available", () => {
+    test("returns ULTIMATE_FALLBACK for all agents and categories when no providers", () => {
+      // #given no providers are available
+      const config = createConfig()
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use ULTIMATE_FALLBACK for everything
+      expect(result).toMatchSnapshot()
+    })
+  })
+
+  describe("single native provider", () => {
+    test("uses Claude models when only Claude is available", () => {
+      // #given only Claude is available
+      const config = createConfig({ hasClaude: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use Claude models per NATIVE_FALLBACK_CHAINS
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses Claude models with isMax20 flag", () => {
+      // #given Claude is available with Max 20 plan
+      const config = createConfig({ hasClaude: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models for Sisyphus
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses OpenAI models when only OpenAI is available", () => {
+      // #given only OpenAI is available
+      const config = createConfig({ hasOpenAI: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use OpenAI models
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses OpenAI models with isMax20 flag", () => {
+      // #given OpenAI is available with Max 20 plan
+      const config = createConfig({ hasOpenAI: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses Gemini models when only Gemini is available", () => {
+      // #given only Gemini is available
+      const config = createConfig({ hasGemini: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use Gemini models
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses Gemini models with isMax20 flag", () => {
+      // #given Gemini is available with Max 20 plan
+      const config = createConfig({ hasGemini: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models
+      expect(result).toMatchSnapshot()
+    })
+  })
+
+  describe("all native providers", () => {
+    test("uses preferred models from fallback chains when all natives available", () => {
+      // #given all native providers are available
+      const config = createConfig({
+        hasClaude: true,
+        hasOpenAI: true,
+        hasGemini: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use first provider in each fallback chain
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses preferred models with isMax20 flag when all natives available", () => {
+      // #given all native providers are available with Max 20 plan
+      const config = createConfig({
+        hasClaude: true,
+        hasOpenAI: true,
+        hasGemini: true,
+        isMax20: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models
+      expect(result).toMatchSnapshot()
+    })
+  })
+
+  describe("fallback providers", () => {
+    test("uses OpenCode Zen models when only OpenCode Zen is available", () => {
+      // #given only OpenCode Zen is available
+      const config = createConfig({ hasOpencodeZen: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use OPENCODE_ZEN_MODELS
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses OpenCode Zen models with isMax20 flag", () => {
+      // #given OpenCode Zen is available with Max 20 plan
+      const config = createConfig({ hasOpencodeZen: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses GitHub Copilot models when only Copilot is available", () => {
+      // #given only GitHub Copilot is available
+      const config = createConfig({ hasCopilot: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use GITHUB_COPILOT_MODELS
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses GitHub Copilot models with isMax20 flag", () => {
+      // #given GitHub Copilot is available with Max 20 plan
+      const config = createConfig({ hasCopilot: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses ZAI model for librarian when only ZAI is available", () => {
+      // #given only ZAI is available
+      const config = createConfig({ hasZaiCodingPlan: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use ZAI_MODEL for librarian
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses ZAI model for librarian with isMax20 flag", () => {
+      // #given ZAI is available with Max 20 plan
+      const config = createConfig({ hasZaiCodingPlan: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use ZAI_MODEL for librarian
+      expect(result).toMatchSnapshot()
+    })
+  })
+
+  describe("mixed provider scenarios", () => {
+    test("uses Claude + OpenCode Zen combination", () => {
+      // #given Claude and OpenCode Zen are available
+      const config = createConfig({
+        hasClaude: true,
+        hasOpencodeZen: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should prefer Claude (native) over OpenCode Zen
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses OpenAI + Copilot combination", () => {
+      // #given OpenAI and Copilot are available
+      const config = createConfig({
+        hasOpenAI: true,
+        hasCopilot: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should prefer OpenAI (native) over Copilot
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses Claude + ZAI combination (librarian uses ZAI)", () => {
+      // #given Claude and ZAI are available
+      const config = createConfig({
+        hasClaude: true,
+        hasZaiCodingPlan: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then librarian should use ZAI, others use Claude
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses Gemini + Claude combination (explore uses Gemini)", () => {
+      // #given Gemini and Claude are available
+      const config = createConfig({
+        hasGemini: true,
+        hasClaude: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then explore should use Gemini flash
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses all fallback providers together", () => {
+      // #given all fallback providers are available
+      const config = createConfig({
+        hasOpencodeZen: true,
+        hasCopilot: true,
+        hasZaiCodingPlan: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should prefer OpenCode Zen, but librarian uses ZAI
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses all providers together", () => {
+      // #given all providers are available
+      const config = createConfig({
+        hasClaude: true,
+        hasOpenAI: true,
+        hasGemini: true,
+        hasOpencodeZen: true,
+        hasCopilot: true,
+        hasZaiCodingPlan: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should prefer native providers, librarian uses ZAI
+      expect(result).toMatchSnapshot()
+    })
+
+    test("uses all providers with isMax20 flag", () => {
+      // #given all providers are available with Max 20 plan
+      const config = createConfig({
+        hasClaude: true,
+        hasOpenAI: true,
+        hasGemini: true,
+        hasOpencodeZen: true,
+        hasCopilot: true,
+        hasZaiCodingPlan: true,
+        isMax20: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should use higher capability models
+      expect(result).toMatchSnapshot()
+    })
+  })
+
+  describe("explore agent special cases", () => {
+    test("explore uses Gemini flash when Gemini available", () => {
+      // #given Gemini is available
+      const config = createConfig({ hasGemini: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then explore should use gemini-3-flash-preview
+      expect(result.agents?.explore?.model).toBe("google/gemini-3-flash-preview")
+    })
+
+    test("explore uses Claude haiku when Claude + isMax20 but no Gemini", () => {
+      // #given Claude is available with Max 20 plan but no Gemini
+      const config = createConfig({ hasClaude: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then explore should use claude-haiku-4-5
+      expect(result.agents?.explore?.model).toBe("anthropic/claude-haiku-4-5")
+    })
+
+    test("explore uses grok-code when Claude without isMax20 and no Gemini", () => {
+      // #given Claude is available without Max 20 plan and no Gemini
+      const config = createConfig({ hasClaude: true, isMax20: false })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then explore should use grok-code
+      expect(result.agents?.explore?.model).toBe("opencode/grok-code")
+    })
+
+    test("explore uses grok-code when only OpenAI available", () => {
+      // #given only OpenAI is available
+      const config = createConfig({ hasOpenAI: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then explore should use grok-code (fallback)
+      expect(result.agents?.explore?.model).toBe("opencode/grok-code")
+    })
+  })
+
+  describe("Sisyphus agent special cases", () => {
+    test("Sisyphus uses sisyphus-high capability when isMax20 is true", () => {
+      // #given Claude is available with Max 20 plan
+      const config = createConfig({ hasClaude: true, isMax20: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then Sisyphus should use opus (sisyphus-high)
+      expect(result.agents?.Sisyphus?.model).toBe("anthropic/claude-opus-4-5")
+    })
+
+    test("Sisyphus uses sisyphus-low capability when isMax20 is false", () => {
+      // #given Claude is available without Max 20 plan
+      const config = createConfig({ hasClaude: true, isMax20: false })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then Sisyphus should use sonnet (sisyphus-low)
+      expect(result.agents?.Sisyphus?.model).toBe("anthropic/claude-sonnet-4-5")
+    })
+  })
+
+  describe("librarian agent special cases", () => {
+    test("librarian uses ZAI when ZAI is available regardless of other providers", () => {
+      // #given ZAI and Claude are available
+      const config = createConfig({
+        hasClaude: true,
+        hasZaiCodingPlan: true,
+      })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then librarian should use ZAI_MODEL
+      expect(result.agents?.librarian?.model).toBe("zai-coding-plan/glm-4.7")
+    })
+
+    test("librarian uses claude-sonnet when ZAI not available but Claude is", () => {
+      // #given only Claude is available (no ZAI)
+      const config = createConfig({ hasClaude: true })
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then librarian should use claude-sonnet-4-5 (third in fallback chain after ZAI and opencode/glm)
+      expect(result.agents?.librarian?.model).toBe("anthropic/claude-sonnet-4-5")
+    })
+  })
+
+  describe("schema URL", () => {
+    test("always includes correct schema URL", () => {
+      // #given any config
+      const config = createConfig()
+
+      // #when generateModelConfig is called
+      const result = generateModelConfig(config)
+
+      // #then should include correct schema URL
+      expect(result.$schema).toBe(
+        "https://raw.githubusercontent.com/code-yeongyu/oh-my-opencode/master/assets/oh-my-opencode.schema.json"
+      )
+    })
+  })
+})
diff --git a/src/cli/model-fallback.ts b/src/cli/model-fallback.ts
index 206a72768..11dd409c1 100644
--- a/src/cli/model-fallback.ts
+++ b/src/cli/model-fallback.ts
@@ -1,17 +1,10 @@
+import {
+  AGENT_MODEL_REQUIREMENTS,
+  CATEGORY_MODEL_REQUIREMENTS,
+  type FallbackEntry,
+} from "../shared/model-requirements"
 import type { InstallConfig } from "./types"
 
-type NativeProvider = "claude" | "openai" | "gemini"
-
-type ModelCapability =
-  | "unspecified-high"
-  | "unspecified-low"
-  | "quick"
-  | "ultrabrain"
-  | "visual-engineering"
-  | "artistry"
-  | "writing"
-  | "glm"
-
 interface ProviderAvailability {
   native: {
     claude: boolean
@@ -41,106 +34,8 @@ export interface GeneratedOmoConfig {
   [key: string]: unknown
 }
 
-interface NativeFallbackEntry {
-  provider: NativeProvider
-  model: string
-}
-
-const NATIVE_FALLBACK_CHAINS: Record<ModelCapability, NativeFallbackEntry[]> = {
-  "unspecified-high": [
-    { provider: "claude", model: "anthropic/claude-opus-4-5" },
-    { provider: "openai", model: "openai/gpt-5.2" },
-    { provider: "gemini", model: "google/gemini-3-pro-preview" },
-  ],
-  "unspecified-low": [
-    { provider: "claude", model: "anthropic/claude-sonnet-4-5" },
-    { provider: "openai", model: "openai/gpt-5.2" },
-    { provider: "gemini", model: "google/gemini-3-flash-preview" },
-  ],
-  quick: [
-    { provider: "claude", model: "anthropic/claude-haiku-4-5" },
-    { provider: "openai", model: "openai/gpt-5.1-codex-mini" },
-    { provider: "gemini", model: "google/gemini-3-flash-preview" },
-  ],
-  ultrabrain: [
-    { provider: "openai", model: "openai/gpt-5.2-codex" },
-    { provider: "claude", model: "anthropic/claude-opus-4-5" },
-    { provider: "gemini", model: "google/gemini-3-pro-preview" },
-  ],
-  "visual-engineering": [
-    { provider: "gemini", model: "google/gemini-3-pro-preview" },
-    { provider: "openai", model: "openai/gpt-5.2" },
-    { provider: "claude", model: "anthropic/claude-sonnet-4-5" },
-  ],
-  artistry: [
-    { provider: "gemini", model: "google/gemini-3-pro-preview" },
-    { provider: "openai", model: "openai/gpt-5.2" },
-    { provider: "claude", model: "anthropic/claude-opus-4-5" },
-  ],
-  writing: [
-    { provider: "gemini", model: "google/gemini-3-flash-preview" },
-    { provider: "openai", model: "openai/gpt-5.2" },
-    { provider: "claude", model: "anthropic/claude-sonnet-4-5" },
-  ],
-  glm: [],
-}
-
-const OPENCODE_ZEN_MODELS: Record<ModelCapability, string> = {
-  "unspecified-high": "opencode/claude-opus-4-5",
-  "unspecified-low": "opencode/claude-sonnet-4-5",
-  quick: "opencode/claude-haiku-4-5",
-  ultrabrain: "opencode/gpt-5.2-codex",
-  "visual-engineering": "opencode/gemini-3-pro",
-  artistry: "opencode/gemini-3-pro",
-  writing: "opencode/gemini-3-flash",
-  glm: "opencode/glm-4.7-free",
-}
-
-const GITHUB_COPILOT_MODELS: Record<ModelCapability, string> = {
-  "unspecified-high": "github-copilot/claude-opus-4.5",
-  "unspecified-low": "github-copilot/claude-sonnet-4.5",
-  quick: "github-copilot/claude-haiku-4.5",
-  ultrabrain: "github-copilot/gpt-5.2-codex",
-  "visual-engineering": "github-copilot/gemini-3-pro-preview",
-  artistry: "github-copilot/gemini-3-pro-preview",
-  writing: "github-copilot/gemini-3-flash-preview",
-  glm: "github-copilot/gpt-5.2",
-}
-
 const ZAI_MODEL = "zai-coding-plan/glm-4.7"
 
-interface AgentRequirement {
-  capability: ModelCapability
-  variant?: string
-}
-
-const AGENT_REQUIREMENTS: Record<string, AgentRequirement> = {
-  Sisyphus: { capability: "unspecified-high" },
-  oracle: { capability: "ultrabrain", variant: "high" },
-  librarian: { capability: "glm" },
-  explore: { capability: "quick" },
-  "multimodal-looker": { capability: "visual-engineering" },
-  "Prometheus (Planner)": { capability: "unspecified-high" },
-  "Metis (Plan Consultant)": { capability: "unspecified-high" },
-  "Momus (Plan Reviewer)": { capability: "ultrabrain", variant: "medium" },
-  Atlas: { capability: "unspecified-high" },
-}
-
-interface CategoryRequirement {
-  capability: ModelCapability
-  variant?: string
-}
-
-const CATEGORY_REQUIREMENTS: Record<string, CategoryRequirement> = {
-  "visual-engineering": { capability: "visual-engineering" },
-  ultrabrain: { capability: "ultrabrain" },
-  artistry: { capability: "artistry", variant: "max" },
-  quick: { capability: "quick" },
-  "unspecified-low": { capability: "unspecified-low" },
-  "unspecified-high": { capability: "unspecified-high" },
-  writing: { capability: "writing" },
-}
-
 const ULTIMATE_FALLBACK = "opencode/glm-4.7-free"
 const SCHEMA_URL = "https://raw.githubusercontent.com/code-yeongyu/oh-my-opencode/master/assets/oh-my-opencode.schema.json"
 
@@ -158,31 +53,46 @@ function toProviderAvailability(config: InstallConfig): ProviderAvailability {
   }
 }
 
-function resolveModel(capability: ModelCapability, avail: ProviderAvailability): string {
-  const nativeChain = NATIVE_FALLBACK_CHAINS[capability]
-  for (const entry of nativeChain) {
-    if (avail.native[entry.provider]) {
-      return entry.model
-    }
+function isProviderAvailable(provider: string, avail: ProviderAvailability): boolean {
+  const mapping: Record<string, boolean> = {
+    anthropic: avail.native.claude,
+    openai: avail.native.openai,
+    google: avail.native.gemini,
+    "github-copilot": avail.copilot,
+    opencode: avail.opencodeZen,
+    "zai-coding-plan": avail.zai,
   }
-
-  if (avail.opencodeZen) {
-    return OPENCODE_ZEN_MODELS[capability]
-  }
-
-  if (avail.copilot) {
-    return GITHUB_COPILOT_MODELS[capability]
-  }
-
-  if (avail.zai) {
-    return ZAI_MODEL
-  }
-
-  return ULTIMATE_FALLBACK
+  return mapping[provider] ?? false
 }
 
-function resolveClaudeCapability(avail: ProviderAvailability): ModelCapability {
-  return avail.isMaxPlan ? "unspecified-high" : "unspecified-low"
+function resolveModelFromChain(
+  fallbackChain: FallbackEntry[],
+  avail: ProviderAvailability
+): { model: string; variant?: string } | null {
+  for (const entry of fallbackChain) {
+    for (const provider of entry.providers) {
+      if (isProviderAvailable(provider, avail)) {
+        return {
+          model: `${provider}/${entry.model}`,
+          variant: entry.variant,
+        }
+      }
+    }
+  }
+  return null
+}
+
+function getSisyphusFallbackChain(isMaxPlan: boolean): FallbackEntry[] {
+  // Sisyphus uses opus when isMaxPlan, sonnet otherwise
+  if (isMaxPlan) {
+    return AGENT_MODEL_REQUIREMENTS.Sisyphus.fallbackChain
+  }
+  // For non-max plan, use sonnet instead of opus
+  return [
+    { providers: ["anthropic", "github-copilot", "opencode"], model: "claude-sonnet-4-5" },
+    { providers: ["openai", "github-copilot", "opencode"], model: "gpt-5.2", variant: "high" },
+    { providers: ["google", "github-copilot", "opencode"], model: "gemini-3-pro-preview" },
+  ]
 }
 
 export function generateModelConfig(config: InstallConfig): GeneratedOmoConfig {
@@ -199,10 +109,10 @@ export function generateModelConfig(config: InstallConfig): GeneratedOmoConfig {
     return {
       $schema: SCHEMA_URL,
       agents: Object.fromEntries(
-        Object.keys(AGENT_REQUIREMENTS).map((role) => [role, { model: ULTIMATE_FALLBACK }])
+        Object.keys(AGENT_MODEL_REQUIREMENTS).map((role) => [role, { model: ULTIMATE_FALLBACK }])
       ),
       categories: Object.fromEntries(
-        Object.keys(CATEGORY_REQUIREMENTS).map((cat) => [cat, { model: ULTIMATE_FALLBACK }])
+        Object.keys(CATEGORY_MODEL_REQUIREMENTS).map((cat) => [cat, { model: ULTIMATE_FALLBACK }])
       ),
     }
   }
@@ -210,28 +120,52 @@ export function generateModelConfig(config: InstallConfig): GeneratedOmoConfig {
   const agents: Record<string, AgentConfig> = {}
   const categories: Record<string, CategoryConfig> = {}
 
-  const claudeCapability = resolveClaudeCapability(avail)
-
-  for (const [role, req] of Object.entries(AGENT_REQUIREMENTS)) {
+  for (const [role, req] of Object.entries(AGENT_MODEL_REQUIREMENTS)) {
+    // Special case: librarian always uses ZAI first if available
     if (role === "librarian" && avail.zai) {
       agents[role] = { model: ZAI_MODEL }
-    } else if (role === "explore") {
-      if (avail.native.claude && avail.isMaxPlan) {
+      continue
+    }
+
+    // Special case: explore has custom Gemini → Claude → Grok logic
+    if (role === "explore") {
+      if (avail.native.gemini) {
+        agents[role] = { model: "google/gemini-3-flash-preview" }
+      } else if (avail.native.claude && avail.isMaxPlan) {
         agents[role] = { model: "anthropic/claude-haiku-4-5" }
       } else {
         agents[role] = { model: "opencode/grok-code" }
       }
+      continue
+    }
+
+    // Special case: Sisyphus uses different fallbackChain based on isMaxPlan
+    const fallbackChain =
+      role === "Sisyphus" ? getSisyphusFallbackChain(avail.isMaxPlan) : req.fallbackChain
+
+    const resolved = resolveModelFromChain(fallbackChain, avail)
+    if (resolved) {
+      const variant = resolved.variant ?? req.variant
+      agents[role] = variant ? { model: resolved.model, variant } : { model: resolved.model }
     } else {
-      const capability = req.capability === "unspecified-high" ? claudeCapability : req.capability
-      const model = resolveModel(capability, avail)
-      agents[role] = req.variant ? { model, variant: req.variant } : { model }
+      agents[role] = { model: ULTIMATE_FALLBACK }
     }
   }
 
-  for (const [cat, req] of Object.entries(CATEGORY_REQUIREMENTS)) {
-    const capability = req.capability === "unspecified-high" ? claudeCapability : req.capability
-    const model = resolveModel(capability, avail)
-    categories[cat] = req.variant ? { model, variant: req.variant } : { model }
+  for (const [cat, req] of Object.entries(CATEGORY_MODEL_REQUIREMENTS)) {
+    // Special case: unspecified-high downgrades to unspecified-low when not isMaxPlan
+    const fallbackChain =
+      cat === "unspecified-high" && !avail.isMaxPlan
+        ? CATEGORY_MODEL_REQUIREMENTS["unspecified-low"].fallbackChain
+        : req.fallbackChain
+
+    const resolved = resolveModelFromChain(fallbackChain, avail)
+    if (resolved) {
+      const variant = resolved.variant ?? req.variant
+      categories[cat] = variant ? { model: resolved.model, variant } : { model: resolved.model }
+    } else {
+      categories[cat] = { model: ULTIMATE_FALLBACK }
+    }
   }
 
   return {