fix(cliproxy): disable 1M extended context for opus 4.6 (256k limit) (#492)

* fix(cliproxy): disable 1M extended context for gemini-claude-opus-4-6-thinking

Antigravity backend only supports 256k context window for this model,
not 1M as previously declared. Set extendedContext: false with TODO
comment for easy re-enable when backend adds support.

Closes #490

* fix(cliproxy): strip [1m] suffix at runtime for models without extended context

Users with existing [1m] in saved agy.settings.json will now have it
automatically stripped at runtime when the model no longer supports
extended context. Prevents misleading context window claims.

src/cliproxy/config/extended-context-config.ts

@@ -85,7 +85,25 @@ export function applyExtendedContextConfig(
   const baseModel = envVars.ANTHROPIC_MODEL || '';
   const cleanModelId = stripModelSuffixes(baseModel);
 
+  // Tier model env vars to apply/strip extended context suffix
+  const tierModels = [
+    'ANTHROPIC_DEFAULT_OPUS_MODEL',
+    'ANTHROPIC_DEFAULT_SONNET_MODEL',
+    'ANTHROPIC_DEFAULT_HAIKU_MODEL',
+  ] as const;
+
   if (!shouldApplyExtendedContext(provider, cleanModelId, extendedContextOverride)) {
+    // Strip [1m] suffix from models that no longer support extended context
+    // (e.g., user had it enabled before backend dropped support)
+    if (envVars.ANTHROPIC_MODEL?.toLowerCase().endsWith('[1m]')) {
+      envVars.ANTHROPIC_MODEL = envVars.ANTHROPIC_MODEL.replace(/\[1m\]$/i, '');
+    }
+    for (const tierVar of tierModels) {
+      const model = envVars[tierVar];
+      if (model?.toLowerCase().endsWith('[1m]')) {
+        envVars[tierVar] = model.replace(/\[1m\]$/i, '');
+      }
+    }
     return;
   }
 
@@ -95,11 +113,6 @@ export function applyExtendedContextConfig(
   }
 
   // Apply to tier models if they support extended context
-  const tierModels = [
-    'ANTHROPIC_DEFAULT_OPUS_MODEL',
-    'ANTHROPIC_DEFAULT_SONNET_MODEL',
-    'ANTHROPIC_DEFAULT_HAIKU_MODEL',
-  ] as const;
 
   for (const tierVar of tierModels) {
     const model = envVars[tierVar];

src/cliproxy/model-catalog.ts

@@ -78,7 +78,7 @@ export const MODEL_CATALOG: Partial<Record<CLIProxyProvider, ProviderCatalog>> =
       {
         id: 'gemini-claude-opus-4-6-thinking',
         name: 'Claude Opus 4.6 Thinking',
-        description: 'Latest flagship, 1M context, extended thinking',
+        description: 'Latest flagship, extended thinking',
         thinking: {
           type: 'budget',
           min: 1024,
@@ -86,7 +86,9 @@ export const MODEL_CATALOG: Partial<Record<CLIProxyProvider, ProviderCatalog>> =
           zeroAllowed: true,
           dynamicAllowed: true,
         },
-        extendedContext: true,
+        // TODO: Re-enable when Antigravity backend supports 1M context (currently 256k)
+        // extendedContext: true,
+        extendedContext: false,
       },
       {
         id: 'gemini-claude-opus-4-5-thinking',

tests/unit/cliproxy/extended-context-config.test.ts

@@ -151,4 +151,23 @@ describe('applyExtendedContextConfig', () => {
     applyExtendedContextConfig(env, 'gemini', undefined);
     expect(env.ANTHROPIC_MODEL).toBeUndefined();
   });
+
+  it('strips [1m] suffix from models that no longer support extended context', () => {
+    // Simulates user who had [1m] in saved settings before support was removed
+    const env: NodeJS.ProcessEnv = {
+      ANTHROPIC_MODEL: 'gemini-claude-opus-4-6-thinking[1m]',
+      ANTHROPIC_DEFAULT_OPUS_MODEL: 'gemini-claude-opus-4-6-thinking[1m]',
+    };
+    applyExtendedContextConfig(env, 'agy', undefined);
+    expect(env.ANTHROPIC_MODEL).toBe('gemini-claude-opus-4-6-thinking');
+    expect(env.ANTHROPIC_DEFAULT_OPUS_MODEL).toBe('gemini-claude-opus-4-6-thinking');
+  });
+
+  it('strips [1m] suffix when --no-1m is explicit even if model has it', () => {
+    const env: NodeJS.ProcessEnv = {
+      ANTHROPIC_MODEL: 'gemini-2.5-pro[1m]',
+    };
+    applyExtendedContextConfig(env, 'gemini', false);
+    expect(env.ANTHROPIC_MODEL).toBe('gemini-2.5-pro');
+  });
 });

ui/src/components/ui/badge.tsx

@@ -23,8 +23,7 @@ const badgeVariants = cva(
 );
 
 interface BadgeProps
-  extends React.HTMLAttributes<HTMLDivElement>,
-    VariantProps<typeof badgeVariants> {}
+  extends React.HTMLAttributes<HTMLDivElement>, VariantProps<typeof badgeVariants> {}
 
 function Badge({ className, variant, ...props }: BadgeProps) {
   return <div className={cn(badgeVariants({ variant }), className)} {...props} />;

ui/src/lib/model-catalogs.ts

@@ -15,8 +15,10 @@ export const MODEL_CATALOGS: Record<string, ProviderCatalog> = {
       {
         id: 'gemini-claude-opus-4-6-thinking',
         name: 'Claude Opus 4.6 Thinking',
-        description: 'Latest flagship, 1M context, extended thinking',
-        extendedContext: true,
+        description: 'Latest flagship, extended thinking',
+        // TODO: Re-enable when Antigravity backend supports 1M context (currently 256k)
+        // extendedContext: true,
+        extendedContext: false,
         presetMapping: {
           default: 'gemini-claude-opus-4-6-thinking',
           opus: 'gemini-claude-opus-4-6-thinking',