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NousResearch/hermes-agent

Gemini thought_signature missing or mishandled in tool calls

Cluster 14488 · agent. Data as of

3 open items. Fix merged in #70280. Check it covers your case.

The short answer

1open issue
2open PRs
12items grouped
Known?
Yes. 12 related items grouped here, 4 issues already closed.
Fix event
A fix was merged to main in PR #70280. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this partially resolved, deciding PR #70280. That is separate from the fix event.
Still open
1 issue and 2 PRs.

Multiple bug reports and fix attempts centered on Gemini's thought_signature field being absent, dropped, or mishandled during streaming, tool calls, and multi-agent (MoA) aggregator scenarios. The cluster covers detection of the problem across different contexts and various proposed or attempted remediation approaches.

Open issues1

  • Issue#66587[Bug]: HTTP 400: Gemini HTTP 400 (INVALID_ARGUMENT): Function call is missing thought_signature in functionCall parts.

Open PRs2

  • PR#104345fix(chat-completions): inject thought_signature sentinel for Gemini targets
  • PR#124090fix(gemini): gate tool call thought signatures on Gemini 3+ models

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

  • #70280 fix(moa): thought-signature integrity, stream close on interrupt, facade restore, advisor attribution (cluster salvage)

    merged to main

    files: agent/agent_init.py, agent/agent_runtime_helpers.py, agent/auxiliary_client.py, agent/chat_completion_helpers.py, agent/conversation_loop.py, agent/gemini_native_adapter.py, agent/moa_loop.py, contributors/emails/[redacted:email], tests/agent/test_gemini_native_adapter.py, tests/run_agent/test_moa_loop_mode.py, tests/run_agent/test_streaming.py

4 PRs closed without merging

From the close comments: merged via another change 2 · closed without comment 1 · duplicate 1

  • #65127 fix(gemini): emit thoughtSignature sentinel for cross-provider/MoA tool calls in native adapter · duplicate → #15676
  • #65294 fix(gemini): emit thoughtSignature sentinel for cross-provider/MoA tool calls (#65092) · merged via another change → 74a56b7, #70280, #15676, #66212, #65092
  • #66212 fix(agent): preserve Gemini thought_signature in MoA aggregator mode · merged via another change → 74a56b7, #70280, #15676, #65092
  • #117927 fix(gemini): thought signature sentinel replay and parallel tool calls · closed without comment
Closed issues · 4
  • Closed#14488[Bug]: Gemini Model missing thought_signature
  • Closed#15054google3+Error, making it unusable
  • Closed#65092[Bug]: Gemini Model missing thought_signature as being an aggregator in MoA model
  • Closed#67725fix(Gemini functionCall skip) silently transforms tool calls into text narrations - semantic degradation
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 0.16: 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
Merged PRs
#70280
Closed issues
4
Attempts
4 PRs closed without merging
Fix link checked
24 Jul 2026

For your agent

The same facts, typed.

cluster/14488.json
cluster/14488.md