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NousResearch/hermes-agent

Tool schema rewriting causes spurious re-prefill between turns

Cluster 128817 · agent. Data as of

Nothing open on GitHub. Fix merged in #139851 on 16 Oct 2026. Check it covers your case.

The short answer

0open issues
0open PRs
4items grouped
Known?
Yes. 4 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #139851. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #139851. That is separate from the fix event.
Still open
Nothing open on GitHub.

A bug where tool schemas are rewritten or altered between conversation turns triggers unnecessary re-prefilling. The fixes aim to keep already-sent tool schemas byte-identical during prefix preservation and refresh cycles.

Open issues0

No open issues.

Open PRs0

No open pull requests.

Fixes on record

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

  • #139851 fix(tools): between-turn MCP refresh keeps sent tool schemas byte-identical (#128817, salvage #128819)

    merged to main

    files: tests/tools/test_refresh_agent_mcp_tools.py, tools/mcp_tool_agent.py

2 PRs closed without merging

From the close comments: done elsewhere 1 · partial fix 1

  • #128819 fix(tools): stop between-turn refresh from rewriting sent tool schemas · partial fix → 5675fc9, 8d30c4e, 57a2267, c1899de, 08f6575, 12b3e7e, #128817, #129033, #172554
  • #132294 fix(tools): keep already-sent tool schemas byte-identical on preserve_prefix refresh (fixes #128817) · done elsewhere → 1b11d2e, 7533bd2, f5a9361, e94fc4e, 5675fc9, 08f6575, 6f0ce58, 6963db5, 164d5c2, 2a7039b, c1899de, #128817, #128819, #129033, #172554
Closed issues · 1
  • Closed#128817[Bug]: Follow-up turns re-prefill because tool schemas change between turns
How this cluster was grouped
  • Link evidence (structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
  • Pairwise link density 0.50: 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
#139851
Closed issues
1
Attempts
2 PRs closed without merging
Fix link checked
16 Oct 2026

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