fix(google): cover gemini pro zero thinking budget (#68607) (thanks @josmithiii)

CHANGELOG.md

@@ -64,7 +64,7 @@ Docs: https://docs.openclaw.ai
 - Agents/failover: avoid treating bare leading `402 ...` prose as billing errors while still recognizing proxy subscription failures. (#45827) Thanks @junyuc25.
 - Config/$schema: preserve root-authored `$schema` during partial config rewrites without injecting include-only schema URLs into the root config. (#47322) Thanks @EfeDurmaz16.
 - Agents/CLI delivery: run the same reply-media path normalizer the auto-reply flow uses before shipping `openclaw agent --deliver` payloads, so relative `MEDIA:./out/photo.png` tokens resolve against the agent workspace instead of being rejected downstream with `LocalMediaAccessError: Local media path is not under an allowed directory`. Thanks @frankekn.
-- Agents/Google: strip `thinkingBudget=0` for the thinking-required `gemini-2.5-pro` model in the embedded runner Google sanitizer, so requests no longer fail with `Budget 0 is invalid. This model only works in thinking mode.` and the API uses its default thinking behavior instead. Thanks @josmithiii.
+- Agents/Google: strip `thinkingBudget=0` for the thinking-required `gemini-2.5-pro` model in embedded-runner and native Google payloads, so requests no longer fail with `Budget 0 is invalid. This model only works in thinking mode.` and the API uses its default thinking behavior instead. (#68607) Thanks @josmithiii.
 
 ## 2026.4.15
 

src/agents/google-thinking-compat.ts

@@ -0,0 +1,22 @@
+import { normalizeLowercaseStringOrEmpty } from "../shared/string-coerce.js";
+
+// Gemini 2.5 Pro only works in thinking mode and rejects thinkingBudget=0 with
+// "Budget 0 is invalid. This model only works in thinking mode."
+export function isGoogleThinkingRequiredModel(modelId: string): boolean {
+  return normalizeLowercaseStringOrEmpty(modelId).includes("gemini-2.5-pro");
+}
+
+export function stripInvalidGoogleThinkingBudget(params: {
+  thinkingConfig: Record<string, unknown>;
+  modelId?: string;
+}): boolean {
+  if (
+    params.thinkingConfig.thinkingBudget !== 0 ||
+    typeof params.modelId !== "string" ||
+    !isGoogleThinkingRequiredModel(params.modelId)
+  ) {
+    return false;
+  }
+  delete params.thinkingConfig.thinkingBudget;
+  return true;
+}

src/agents/google-transport-stream.test.ts

@@ -295,6 +295,45 @@ describe("google transport stream", () => {
     });
   });
 
+  it("omits disabled thinkingBudget=0 for Gemini 2.5 Pro direct payloads", () => {
+    const params = buildGoogleGenerativeAiParams(
+      buildGeminiModel(),
+      {
+        messages: [{ role: "user", content: "hello", timestamp: 0 }],
+      } as never,
+      {
+        maxTokens: 128,
+      } as never,
+    );
+
+    expect(params.generationConfig).toMatchObject({
+      maxOutputTokens: 128,
+    });
+    expect(params.generationConfig).not.toHaveProperty("thinkingConfig");
+  });
+
+  it("strips explicit thinkingBudget=0 but preserves includeThoughts for Gemini 2.5 Pro", () => {
+    const params = buildGoogleGenerativeAiParams(
+      buildGeminiModel(),
+      {
+        messages: [{ role: "user", content: "hello", timestamp: 0 }],
+      } as never,
+      {
+        thinking: {
+          enabled: true,
+          budgetTokens: 0,
+        },
+      } as never,
+    );
+
+    expect(params.generationConfig).toMatchObject({
+      thinkingConfig: { includeThoughts: true },
+    });
+    expect(params.generationConfig).not.toMatchObject({
+      thinkingConfig: { thinkingBudget: 0 },
+    });
+  });
+
   it("includes cachedContent in direct Gemini payloads when requested", () => {
     const params = buildGoogleGenerativeAiParams(
       buildGeminiModel(),

src/agents/google-transport-stream.ts

@@ -10,6 +10,7 @@ import {
 import { parseGeminiAuth } from "../infra/gemini-auth.js";
 import { normalizeGoogleApiBaseUrl } from "../infra/google-api-base-url.js";
 import { normalizeLowercaseStringOrEmpty } from "../shared/string-coerce.js";
+import { stripInvalidGoogleThinkingBudget } from "./google-thinking-compat.js";
 import { buildGuardedModelFetch } from "./provider-transport-fetch.js";
 import { stripSystemPromptCacheBoundary } from "./system-prompt-cache-boundary.js";
 import { transformTransportMessages } from "./transport-message-transform.js";
@@ -213,14 +214,14 @@ function resolveThinkingLevel(level: ThinkingLevel, modelId: string): GoogleThin
   throw new Error("Unsupported thinking level");
 }
 
-function getDisabledThinkingConfig(modelId: string): Record<string, unknown> {
+function getDisabledThinkingConfig(modelId: string): Record<string, unknown> | undefined {
   if (isGemini3ProModel(modelId)) {
     return { thinkingLevel: "LOW" };
   }
   if (isGemini3FlashModel(modelId)) {
     return { thinkingLevel: "MINIMAL" };
   }
-  return { thinkingBudget: 0 };
+  return normalizeGoogleThinkingConfig(modelId, { thinkingBudget: 0 });
 }
 
 function getGoogleThinkingBudget(
@@ -258,7 +259,7 @@ function resolveGoogleThinkingConfig(
     } else if (typeof options.thinking.budgetTokens === "number") {
       config.thinkingBudget = options.thinking.budgetTokens;
     }
-    return config;
+    return normalizeGoogleThinkingConfig(model.id, config);
   }
   if (!options?.reasoning) {
     return getDisabledThinkingConfig(model.id);
@@ -270,10 +271,18 @@ function resolveGoogleThinkingConfig(
     };
   }
   const budget = getGoogleThinkingBudget(model.id, options.reasoning, options.thinkingBudgets);
-  return {
+  return normalizeGoogleThinkingConfig(model.id, {
     includeThoughts: true,
     ...(typeof budget === "number" ? { thinkingBudget: budget } : {}),
-  };
+  });
+}
+
+function normalizeGoogleThinkingConfig(
+  modelId: string,
+  thinkingConfig: Record<string, unknown>,
+): Record<string, unknown> | undefined {
+  stripInvalidGoogleThinkingBudget({ thinkingConfig, modelId });
+  return Object.keys(thinkingConfig).length > 0 ? thinkingConfig : undefined;
 }
 
 function convertGoogleMessages(model: GoogleTransportModel, context: Context) {

src/agents/pi-embedded-runner/google-stream-wrappers.test.ts

@@ -33,6 +33,17 @@ describe("sanitizeGoogleThinkingPayload — gemini-2.5-pro zero budget", () => {
     expect(payload.config.thinkingConfig).toHaveProperty("includeThoughts", true);
   });
 
+  it("removes thinkingBudget=0 from native Google generationConfig payloads", () => {
+    const payload = {
+      generationConfig: {
+        thinkingConfig: { thinkingBudget: 0, includeThoughts: true },
+      },
+    };
+    sanitizeGoogleThinkingPayload({ payload, modelId: "gemini-2.5-pro" });
+    expect(payload.generationConfig.thinkingConfig).not.toHaveProperty("thinkingBudget");
+    expect(payload.generationConfig.thinkingConfig).toHaveProperty("includeThoughts", true);
+  });
+
   it("keeps thinkingBudget=0 for gemini-2.5-flash (not thinking-required)", () => {
     const payload = {
       config: {

src/agents/pi-embedded-runner/google-stream-wrappers.ts

@@ -2,6 +2,7 @@ import type { StreamFn } from "@mariozechner/pi-agent-core";
 import { streamSimple } from "@mariozechner/pi-ai";
 import type { ThinkLevel } from "../../auto-reply/thinking.js";
 import { normalizeLowercaseStringOrEmpty } from "../../shared/string-coerce.js";
+import { stripInvalidGoogleThinkingBudget } from "../google-thinking-compat.js";
 import { streamWithPayloadPatch } from "./stream-payload-utils.js";
 
 function isGemini31Model(modelId: string): boolean {
@@ -13,12 +14,6 @@ function isGemma4Model(modelId: string): boolean {
   return normalizeLowercaseStringOrEmpty(modelId).startsWith("gemma-4");
 }
 
-// Gemini 2.5 Pro only works in thinking mode and rejects thinkingBudget=0 with
-// "Budget 0 is invalid. This model only works in thinking mode."
-function isThinkingRequiredModel(modelId: string): boolean {
-  return normalizeLowercaseStringOrEmpty(modelId).includes("gemini-2.5-pro");
-}
-
 function mapThinkLevelToGoogleThinkingLevel(
   thinkingLevel: ThinkLevel,
 ): "MINIMAL" | "LOW" | "MEDIUM" | "HIGH" | undefined {
@@ -82,11 +77,27 @@ export function sanitizeGoogleThinkingPayload(params: {
     return;
   }
   const payloadObj = params.payload as Record<string, unknown>;
-  const config = payloadObj.config;
-  if (!config || typeof config !== "object") {
+  sanitizeGoogleThinkingConfigContainer({
+    container: payloadObj.config,
+    modelId: params.modelId,
+    thinkingLevel: params.thinkingLevel,
+  });
+  sanitizeGoogleThinkingConfigContainer({
+    container: payloadObj.generationConfig,
+    modelId: params.modelId,
+    thinkingLevel: params.thinkingLevel,
+  });
+}
+
+function sanitizeGoogleThinkingConfigContainer(params: {
+  container: unknown;
+  modelId?: string;
+  thinkingLevel?: ThinkLevel;
+}): void {
+  if (!params.container || typeof params.container !== "object") {
     return;
   }
-  const configObj = config as Record<string, unknown>;
+  const configObj = params.container as Record<string, unknown>;
   const thinkingConfig = configObj.thinkingConfig;
   if (!thinkingConfig || typeof thinkingConfig !== "object") {
     return;
@@ -123,13 +134,9 @@ export function sanitizeGoogleThinkingPayload(params: {
 
   const thinkingBudget = thinkingConfigObj.thinkingBudget;
 
-  // Gemini 2.5 Pro rejects thinkingBudget=0; remove it so the API uses its default.
   if (
-    thinkingBudget === 0 &&
-    typeof params.modelId === "string" &&
-    isThinkingRequiredModel(params.modelId)
+    stripInvalidGoogleThinkingBudget({ thinkingConfig: thinkingConfigObj, modelId: params.modelId })
   ) {
-    delete thinkingConfigObj.thinkingBudget;
     if (Object.keys(thinkingConfigObj).length === 0) {
       delete configObj.thinkingConfig;
     }