🔧 fix: Filter urlContext in OpenAI transform and add param tests

Add `urlContext` to the Google-specific tool filter set in
`transformToOpenAIConfig` so it doesn't leak into OpenAI-compatible
flows. Also adds tests for url_context via defaultParams, addParams,
and dropParams.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/api/src/endpoints/google/llm.spec.ts

@@ -682,6 +682,57 @@ describe('getGoogleConfig', () => {
       expect(result.tools).toContainEqual({ urlContext: {} });
       expect(result.tools).toHaveLength(2);
     });
+
+    it('should enable url_context via defaultParams', () => {
+      const credentials = {
+        [AuthKeys.GOOGLE_API_KEY]: 'test-api-key',
+      };
+
+      const result = getGoogleConfig(credentials, {
+        modelOptions: {
+          model: 'gemini-2.5-flash',
+        },
+        defaultParams: {
+          url_context: true,
+        },
+      });
+
+      expect(result.tools).toContainEqual({ urlContext: {} });
+    });
+
+    it('should enable url_context via addParams when initially disabled', () => {
+      const credentials = {
+        [AuthKeys.GOOGLE_API_KEY]: 'test-api-key',
+      };
+
+      const result = getGoogleConfig(credentials, {
+        modelOptions: {
+          model: 'gemini-2.5-flash',
+          url_context: false,
+        },
+        addParams: {
+          url_context: true,
+        },
+      });
+
+      expect(result.tools).toContainEqual({ urlContext: {} });
+    });
+
+    it('should disable url_context via dropParams', () => {
+      const credentials = {
+        [AuthKeys.GOOGLE_API_KEY]: 'test-api-key',
+      };
+
+      const result = getGoogleConfig(credentials, {
+        modelOptions: {
+          model: 'gemini-2.5-flash',
+          url_context: true,
+        },
+        dropParams: ['url_context'],
+      });
+
+      expect(result.tools).not.toContainEqual({ urlContext: {} });
+    });
   });
 
   describe('Default and Add Parameters', () => {

packages/api/src/endpoints/openai/transform.ts

@@ -16,7 +16,7 @@ const googleExcludeParams = new Set([
 ]);
 
 /** Google-specific tool types that have no OpenAI-compatible equivalent */
-const googleToolsToFilter = new Set(['googleSearch']);
+const googleToolsToFilter = new Set(['googleSearch', 'urlContext']);
 
 export type ConfigTools = Array<Record<string, unknown>> | Array<GoogleAIToolType>;
 
@@ -134,11 +134,13 @@ export function transformToOpenAIConfig({
 
   /**
    * Filter out provider-specific tools that have no OpenAI equivalent.
-   * Exception: If web_search was explicitly enabled via addParams or defaultParams,
-   * preserve googleSearch tools (pass through in Google-native format).
+   * Exception: If web_search or url_context was explicitly enabled via addParams or defaultParams,
+   * preserve the corresponding Google-native tools (googleSearch, urlContext).
    */
   const webSearchExplicitlyEnabled =
     addParams?.web_search === true || defaultParams?.web_search === true;
+  const urlContextExplicitlyEnabled =
+    addParams?.url_context === true || defaultParams?.url_context === true;
 
   const filterGoogleTool = (tool: unknown): boolean => {
     if (!isGoogle) {
@@ -149,11 +151,18 @@ export function transformToOpenAIConfig({
     }
     const toolKeys = Object.keys(tool as Record<string, unknown>);
     const isGoogleSpecificTool = toolKeys.some((key) => googleToolsToFilter.has(key));
-    /** Preserve googleSearch if web_search was explicitly enabled */
-    if (isGoogleSpecificTool && webSearchExplicitlyEnabled) {
-      return true;
+    if (isGoogleSpecificTool) {
+      const hasGoogleSearch = toolKeys.includes('googleSearch');
+      const hasUrlContext = toolKeys.includes('urlContext');
+      if (hasGoogleSearch && webSearchExplicitlyEnabled) {
+        return true;
+      }
+      if (hasUrlContext && urlContextExplicitlyEnabled) {
+        return true;
+      }
+      return false;
     }
-    return !isGoogleSpecificTool;
+    return true;
   };
 
   const filteredTools = Array.isArray(tools) ? tools.filter(filterGoogleTool) : [];