tools/list is rejected: three outputSchemas declare a bare oneOf with no type

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
72/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
typescript

Research direction

Start by locating the tools/list outputSchema declarations for rename_document, archive_document, and restore_document, then inspect how the output schema array is assembled. Ensure the advertisement remains valid when a oneOf output schema is present, and verify that tools/list accepts these tools and future oneOf entries.

Written by the indexing model from the issue text.

Description

rename_document, archive_document and restore_document declare an outputSchema that is a bare oneOf with no type.

MCP types a tool's outputSchema as an object schema. A client that validates the advertisement rejects it — and rejects the whole tools/list response rather than the offending tool, so every tool goes unavailable, not the three that are malformed. Claude Code reports:

chopin: https://<host>/mcp (HTTP) - ! Connected · tools fetch failed
Invalid input (at tools.3.outputSchema.type)

The health line leads with Connected and buries the reason, so the failure reads as a healthy server.

Both branches of each oneOf are already object schemas. The constraint belongs to the array rather than to those three entries: any tool added later with a oneOf output takes the advertisement dark the same way.

Dominant language
TypeScript
Stars
351
Forks
20
Avg merge
13h 49m
Merged PRs (30d)
34

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