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NousResearch/hermes-agent

MCP schema repair corrupts conditional constraint branches

Cluster 107141 · mcp. Data as of

1 open item. Fix merged in #118463 on 21 Sep 2026. Check it covers your case.

The short answer

0open issues
1open PR
4items grouped
Known?
Yes. 4 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #118463. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #118463. That is separate from the fix event.
Still open
0 issues and 1 PR.

A bug causes the MCP schema sanitization process to incorrectly prune or overwrite required fields and type annotations inside oneOf, not, if/then/else, and similar conditional schema branches. Multiple fixes address preserving these constraint fragments through schema repair.

Open issues0

No open issues.

Open PRs1

  • PR#104548fix(mcp): preserve schema maps and independent required constraints

Fixes on record

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

  • #118463 fix(mcp): if/then/else and oneOf constraint fragments survive schema repair (#107141, salvage #117872 #107146)

    merged to main

    files: agent/moonshot_schema.py, contributors/emails/[email protected], tests/agent/test_moonshot_schema.py, tests/tools/test_schema_sanitizer.py, tools/mcp_tool_schema.py

1 PR closed without merging

From the close comments: merged via another change 1

  • #107146 fix(moonshot): stop stamping a synthetic type on if/then/else nodes · merged via another change → e7c5141, dc0915c, #118463, #117872
Closed issues · 1
  • Closed#107141[Bug]: MCP schema sanitize chain prunes required inside oneOf/not/if branches, turning mutex constraints always-false (all calls rejected)
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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
mcp
Merged PRs
#118463
Closed issues
1
Attempts
1 PR closed without merging
Fix link checked
21 Sep 2026

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