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NousResearch/hermes-agent

Gemini thinking_config malformed request causing 400 errors

Cluster 25123 · agent. Data as of

2 open items. Fix attempted, not merged.

The short answer

1open issue
1open PR
4items grouped
Known?
Yes. 4 related items grouped here, 1 issue already closed.
Fix event
No fix has been merged to main. 1 PR closed without merging; see the attempts below.
Tracker
The maintainers' tracker marks this unresolved. That is separate from the fix event.
Still open
1 issue and 1 PR.

Multiple issues and fixes related to incorrectly structured or inappropriately injected thinking_config in Gemini API requests, resulting in 400 Bad Request errors. Specific cases include double-nesting in extra_body, injection for unsupported models like Gemma and gemini-3-flash-preview, and OpenAI-compat path mismatches.

Open issues1

  • Issue#25123fix: Fallback to gemini-3-flash-preview fails with 400 (thinking_config)

Open PRs1

  • PR#25124fix: exclude gemini-3-flash-preview from thinking_config injection

1 PR closed without merging

From the close comments: done elsewhere 1

  • #32353 fix(agent): exclude gemini-3-flash-preview from thinkingLevel injection (#25123) · done elsewhere
Closed issues · 1
  • Closed#26161[Bug]: Gemini API Failed with 400 Bad Request
How this cluster was grouped
  • Link evidence (partly structural links): some members are connected by structural evidence (shared changed files, or a closing/superseded reference); the rest are joined by an automated relevance judgement over their text.
  • Members outside that structural core may belong to a different underlying problem.
  • Pairwise link density 0.39: the share of item pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. 1.00 means every pair is linked.

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At a glance

Subsystem
agent
Closed issues
1
Attempts
1 PR closed without merging

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