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Gemini 3 integration fail #6050
Description
Description
Gemini3 outputs JSON.
When Gemini3 models are used, everything they output is either thinking blocks or JSON instead of formatting it right.
All Gemini models started acting weird
Sometimes it's ok and they do what i ask, sometimes they fail
This one went ok:
This one failed
OpenCode version
1.0.193
Steps to reproduce
- Open Opencode
- Add Google AI Studio API key
- Choose Gemini 3 Flash/Pro Preview model
- Prompt
Screenshot and/or share link
No response
Operating System
Arch linux
Terminal
Gnome Terminal
Activity
github-actions commentedon Dec 23, 2025
This issue might be a duplicate of existing issues. Please check:
thoughtSignaturesupport #4832: [BUG]: Gemini 3 Pro function calling fails - missingthoughtSignaturesupport - Addresses a critical issue where Gemini 3 Pro fails to handle function calling properly due to missing thoughtSignature preservationFeel free to ignore if none of these address your specific case.
longsman commentedon Dec 23, 2025
I'll add some additional details - because the provider somehow makes a difference.
The OP's output format problems also happens with gemini 3 flash and gemini 3 pro, however:
Openrouter: no output issues for gemini 3 flash
Vercel AI gateway: no output issues for gemini 3 flash.
Opencode Zen: I experience nested json output, sometimes with full content, sometimes empty responses "{}"
I have not experimented with direct google's api provider.
Upon further investigation, I found:
vercel/ai#11396
Which describes this issue upstream, and if I'm not mistaken, opencode zen uses this sdk, although I do no understand why Vercel AI gateway would not have this problem.
I'm having trouble weighing what to do here else just switch providers and wait for upstream.
EDIT: yeah keep an eye on that vercel issue someone making progress, probably best that this just gets resolved upstream.
palekiwi commentedon Dec 24, 2025
I can confirm that
google/gemini-3-pro-preview(direct Google provider via API key) has also started outputting JSONrekram1-node commentedon Dec 24, 2025
I heard a variety of people report degraded performance from gemini models elsewhere, nothing we did has changed... That said I need to do gemini optimizations regardless
rmk40 commentedon Dec 24, 2025
Another confirmation that this issue consistently occurs with the Gemini 3 models.
kaitokid2302 commentedon Dec 25, 2025
This problem occurs for me too; please fix it soon.
longsman commentedon Dec 26, 2025
hey guys double check i believe it's resolved now. because of google. see the vercel issue I linked. @ceo-s see if its resolved
rekram1-node commentedon Dec 26, 2025
Thank you @longsman it does indeed appear to be a google issue thank you for linking this!!!