Gemini Thinking output is added to content instead of thinking chunks.

[jpkraemer]

TanStack AI version

0.2.1

Framework/Library version

React 19.0

Describe the bug and the steps to reproduce it

When I enable thinking for Gemini with:
modelOptions: { thinkingConfig: { includeThoughts: true, thinkingBudget: 500, } }

I receive all the thinking output as part of the content chunks.

This is caused by the processStreamChunks method in the Gemini text adapter:

ai/packages/typescript/ai-gemini/src/adapters/text.ts

Line 214 in 1ce1e88

if (part.text) {

When if (part.text) the code should further check if part.thought is true. If it is we shall yield { type: 'thinking', ... }.

Your Minimal, Reproducible Example - (Sandbox Highly Recommended)

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Screenshots or Videos (Optional)

No response

Do you intend to try to help solve this bug with your own PR?

Maybe, I'll investigate and start debugging

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