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MCP boolean JSON Schema property causes full server failure

NousResearch/hermes-agent · cluster 101669 · mcp

Data as of

3 open items. Fix attempted, not merged.

The short answer

1open issue
2open PRs
4items grouped
Known?
Yes. 4 related items grouped here, 0 issues 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 2 PRs.

A bug where boolean property schemas (e.g. properties.x: true) in MCP tool definitions fail ListToolsResult validation and disable the entire server. The related fixes address isolating rejected tools and accepting boolean JSON Schema property schemas.

Open issues1

  • Issue#101669MCP: boolean property schema (`properties.x: true`) fails ListToolsResult validation and disables the entire server

Open PRs2

  • PR#101804fix(mcp): isolate a tool the SDK rejects instead of parking the whole server
  • PR#102900fix(mcp): accept boolean JSON Schema property schemas on tools/list

1 PR closed without merging

From the close comments: other 1

  • #101810 fix(mcp): accept boolean JSON Schema property schemas on tools/list · other → #102117
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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
Closed issues
0
Attempts
1 PR closed without merging

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