feat(catalog): add Claude Opus 4.8 to Anthropic model registry

Register `claude-opus-4-8` in the cliproxy model catalog, web-server
pricing table, and UI catalog as an additive entry next to 4.7. Defaults
are unchanged (claude provider stays on sonnet-4-6); users opt into 4.8
explicitly via ANTHROPIC_MODEL or the dashboard.

Configuration mirrors 4.7:
- adaptive thinking levels (low through max), max distinct from xhigh
- extendedContext (1M) available
- nativeImageInput
- pricing $5/$25 in/out, $6.25/$0.5 cache

Built [OnSteroids](https://onsteroids.ai)

src/cliproxy/__tests__/model-catalog.test.js

@@ -155,6 +155,19 @@ describe('Model Catalog', () => {
       assert.strictEqual(opus47.extendedContext, true);
     });
 
+    it('includes Claude Opus 4.8 with adaptive levels and extended context', () => {
+      const { MODEL_CATALOG } = modelCatalog;
+      const opus48 = MODEL_CATALOG.claude.models.find((m) => m.id === 'claude-opus-4-8');
+      assert(opus48, 'Should include Claude Opus 4.8');
+      assert.strictEqual(opus48.name, 'Claude Opus 4.8');
+      // Mirrors 4.7: Anthropic only accepts adaptive thinking levels on the
+      // current Opus generation; budget_tokens is rejected with 400.
+      assert.strictEqual(opus48.thinking.type, 'levels');
+      assert.deepStrictEqual(opus48.thinking.levels, ['low', 'medium', 'high', 'xhigh', 'max']);
+      assert.strictEqual(opus48.thinking.maxLevel, 'max');
+      assert.strictEqual(opus48.extendedContext, true);
+    });
+
     it('retains previous 4.5 snapshot models for explicit selection', () => {
       const { MODEL_CATALOG } = modelCatalog;
       const ids = MODEL_CATALOG.claude.models.map((m) => m.id);

src/cliproxy/__tests__/thinking-validator.test.ts

@@ -51,6 +51,15 @@ describe('Thinking Validator', () => {
       expect(result.warning).toBeUndefined();
     });
 
+    it('should treat max as a distinct top tier on Opus 4.8', () => {
+      // Opus 4.8 inherits 4.7's adaptive thinking surface; max must remain
+      // distinct from xhigh.
+      const result = validateThinking('claude', 'claude-opus-4-8', 'max');
+      expect(result.valid).toBe(true);
+      expect(result.value).toBe('max');
+      expect(result.warning).toBeUndefined();
+    });
+
     it('should still alias max -> xhigh for models without a max level (backcompat)', () => {
       // Codex catalog uses ['low','medium','high','xhigh'] with maxLevel 'xhigh'.
       // User input "max" should map down to xhigh rather than be rejected.

src/cliproxy/model-catalog.ts

@@ -307,10 +307,25 @@ export const MODEL_CATALOG: Partial<Record<CLIProxyProvider, ProviderCatalog>> =
     displayName: 'Claude (Anthropic)',
     defaultModel: 'claude-sonnet-4-6',
     models: [
+      {
+        id: 'claude-opus-4-8',
+        name: 'Claude Opus 4.8',
+        description: 'Latest flagship model',
+        nativeImageInput: true,
+        // Mirrors 4.7: Anthropic accepts only adaptive thinking levels on the
+        // current Opus generation; manual budget_tokens is rejected with 400.
+        thinking: {
+          type: 'levels',
+          levels: ['low', 'medium', 'high', 'xhigh', 'max'],
+          maxLevel: 'max',
+          dynamicAllowed: true,
+        },
+        extendedContext: true,
+      },
       {
         id: 'claude-opus-4-7',
         name: 'Claude Opus 4.7',
-        description: 'Latest flagship model',
+        description: 'Previous flagship model',
         nativeImageInput: true,
         // Opus 4.7 only supports adaptive thinking on the Anthropic API; manual
         // thinking.type: "enabled" with budget_tokens is rejected with 400.
@@ -327,7 +342,7 @@ export const MODEL_CATALOG: Partial<Record<CLIProxyProvider, ProviderCatalog>> =
       {
         id: 'claude-opus-4-6',
         name: 'Claude Opus 4.6',
-        description: 'Previous flagship model',
+        description: 'Older flagship model',
         nativeImageInput: true,
         thinking: {
           type: 'budget',

src/web-server/model-pricing.ts

@@ -243,6 +243,13 @@ const PRICING_REGISTRY: Record<string, ModelPricing> = {
     cacheCreationPerMillion: 6.25,
     cacheReadPerMillion: 0.5,
   },
+  // Claude 4.8 Opus ($5/$25)
+  'claude-opus-4-8': {
+    inputPerMillion: 5.0,
+    outputPerMillion: 25.0,
+    cacheCreationPerMillion: 6.25,
+    cacheReadPerMillion: 0.5,
+  },
 
   // ---------------------------------------------------------------------------
   // OpenAI Models - Source: better-ccusage

tests/unit/model-pricing.test.ts

@@ -168,6 +168,14 @@ describe('model-pricing', () => {
       expect(opus47dated.outputPerMillion).toBe(25.0);
     });
 
+    it('should return correct pricing for Claude Opus 4.8', () => {
+      const opus48 = getModelPricing('claude-opus-4-8');
+      expect(opus48.inputPerMillion).toBe(5.0);
+      expect(opus48.outputPerMillion).toBe(25.0);
+      expect(opus48.cacheCreationPerMillion).toBe(6.25);
+      expect(opus48.cacheReadPerMillion).toBe(0.5);
+    });
+
     it('should not map unknown future model families onto known family pricing', () => {
       const fallback = getModelPricing('unknown-model-xyz');
 
@@ -266,6 +274,17 @@ describe('model-pricing', () => {
       const cost = calculateCost(usage, 'claude-opus-4-7');
       expect(cost).toBe(36.75); // 5 + 25 + 6.25 + 0.5
     });
+
+    it('should calculate Claude Opus 4.8 cost including cache token rates', () => {
+      const usage: TokenUsage = {
+        inputTokens: 1_000_000,
+        outputTokens: 1_000_000,
+        cacheCreationTokens: 1_000_000,
+        cacheReadTokens: 1_000_000,
+      };
+      const cost = calculateCost(usage, 'claude-opus-4-8');
+      expect(cost).toBe(36.75); // 5 + 25 + 6.25 + 0.5
+    });
   });
 
   describe('getKnownModels', () => {
@@ -469,17 +488,15 @@ describe('model-pricing', () => {
     });
 
     it('gracefully ignores malformed cached model entries', () => {
-      setCachedModelsDevRegistry(
-        {
-          openai: {
-            id: 'openai',
-            models: {
-              'null-entry': null,
-              'gpt-5.5': { id: 'gpt-5.5', cost: { input: 5, output: 30 } },
-            },
+      setCachedModelsDevRegistry({
+        openai: {
+          id: 'openai',
+          models: {
+            'null-entry': null,
+            'gpt-5.5': { id: 'gpt-5.5', cost: { input: 5, output: 30 } },
           },
-        } as unknown as Parameters<typeof setCachedModelsDevRegistry>[0]
-      );
+        },
+      } as unknown as Parameters<typeof setCachedModelsDevRegistry>[0]);
 
       expect(() => getModelPricing('openai/gpt-5.5')).not.toThrow();
       expect(getModelPricing('openai/gpt-5.5').inputPerMillion).toBe(5);

ui/src/lib/model-catalogs.ts

@@ -630,10 +630,22 @@ export const MODEL_CATALOGS: Record<string, ProviderCatalog> = {
     displayName: 'Claude (Anthropic)',
     defaultModel: 'claude-sonnet-4-6',
     models: [
+      {
+        id: 'claude-opus-4-8',
+        name: 'Claude Opus 4.8',
+        description: 'Latest flagship model',
+        extendedContext: true,
+        presetMapping: {
+          default: 'claude-opus-4-8',
+          opus: 'claude-opus-4-8',
+          sonnet: 'claude-sonnet-4-6',
+          haiku: 'claude-haiku-4-5-20251001',
+        },
+      },
       {
         id: 'claude-opus-4-7',
         name: 'Claude Opus 4.7',
-        description: 'Latest flagship model',
+        description: 'Previous flagship model',
         extendedContext: true,
         presetMapping: {
           default: 'claude-opus-4-7',
@@ -645,7 +657,7 @@ export const MODEL_CATALOGS: Record<string, ProviderCatalog> = {
       {
         id: 'claude-opus-4-6',
         name: 'Claude Opus 4.6',
-        description: 'Previous flagship model',
+        description: 'Older flagship model',
         extendedContext: true,
         presetMapping: {
           default: 'claude-opus-4-6',

ui/tests/unit/ui/lib/preset-utils.test.ts

@@ -16,12 +16,14 @@ describe('claude preset utils', () => {
     vi.restoreAllMocks();
   });
 
-  it('keeps the claude catalog default on Sonnet 4.6 while exposing Opus 4.7', () => {
+  it('keeps the claude catalog default on Sonnet 4.6 while exposing Opus 4.7 and 4.8', () => {
     const claudeCatalog = MODEL_CATALOGS.claude;
+    const ids = claudeCatalog.models.map((model) => model.id);
 
     expect(claudeCatalog.defaultModel).toBe('claude-sonnet-4-6');
-    expect(claudeCatalog.models.map((model) => model.id)).toContain('claude-opus-4-7');
-    expect(claudeCatalog.models.map((model) => model.id)).toContain('claude-sonnet-4-6');
+    expect(ids).toContain('claude-opus-4-8');
+    expect(ids).toContain('claude-opus-4-7');
+    expect(ids).toContain('claude-sonnet-4-6');
   });
 
   it('applies the default claude preset from the catalog default model mapping', async () => {