fix(agents): prevent /v1beta duplication in Gemini PDF URL (#34369)

Strip trailing /v1beta from baseUrl before appending the version
segment, so callers that already include /v1beta in their base URL
(e.g. subagent-registry) no longer produce /v1beta/v1beta/models/…
which results in a 404 from the Gemini API.

Closes #34312

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

src/agents/tools/pdf-native-providers.ts

@@ -137,10 +137,9 @@ export async function geminiAnalyzePdf(params: {
   }
   parts.push({ text: params.prompt });
 
-  const baseUrl = (params.baseUrl ?? "https://generativelanguage.googleapis.com").replace(
-    /\/+$/,
-    "",
-  );
+  const baseUrl = (params.baseUrl ?? "https://generativelanguage.googleapis.com")
+    .replace(/\/+$/, "")
+    .replace(/\/v1beta$/, "");
   const url = `${baseUrl}/v1beta/models/${encodeURIComponent(params.modelId)}:generateContent?key=${encodeURIComponent(apiKey)}`;
 
   const res = await fetch(url, {

src/agents/tools/pdf-tool.test.ts

@@ -711,6 +711,26 @@ describe("native PDF provider API calls", () => {
       "apiKey required",
     );
   });
+
+  it("geminiAnalyzePdf does not duplicate /v1beta when baseUrl already includes it", async () => {
+    const { geminiAnalyzePdf } = await import("./pdf-native-providers.js");
+    const fetchMock = mockFetchResponse({
+      ok: true,
+      json: async () => ({
+        candidates: [{ content: { parts: [{ text: "ok" }] } }],
+      }),
+    });
+
+    await geminiAnalyzePdf(
+      makeGeminiAnalyzeParams({
+        baseUrl: "https://generativelanguage.googleapis.com/v1beta",
+      }),
+    );
+
+    const [url] = fetchMock.mock.calls[0];
+    expect(url).toContain("/v1beta/models/");
+    expect(url).not.toContain("/v1beta/v1beta");
+  });
 });
 
 // ---------------------------------------------------------------------------