fix(antigravity): drop requestType "agent" to avoid false 429 RESOURCE_EXHAUSTED

open-sse/translator/request/openai-to-gemini.js

@@ -279,10 +279,11 @@ function wrapInCloudCodeEnvelope(model, geminiCLI, credentials = null, isAntigra
     }
   };
 
-  // Antigravity specific fields
-  if (isAntigravity) {
-    envelope.requestType = "agent";
-  } else {
+  // Antigravity specific fields.
+  // NOTE: the official Antigravity client omits `requestType` entirely on the
+  // agent (chat) path. Sending `requestType: "agent"` triggers a detail-free
+  // 429 RESOURCE_EXHAUSTED even with quota available.
+  if (!isAntigravity) {
     // Keep safetySettings for Gemini CLI
     envelope.request.safetySettings = geminiCLI.safetySettings;
   }
@@ -305,7 +306,8 @@ function wrapInCloudCodeEnvelopeForClaude(model, claudeRequest, credentials = nu
     model: model,
     userAgent: "antigravity",
     requestId: `agent-${generateUUID()}`,
-    requestType: "agent",
+    // NOTE: official Antigravity client omits `requestType` on the agent (chat)
+    // path — see the note in wrapInCloudCodeEnvelope() above.
     request: {
       sessionId: toNumericSessionId(credentials?._clientSessionId) || deriveSessionId(credentials?.email || credentials?.connectionId),
       contents: [],