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fix(server): disable listChanged capability in V1x protocol mode (closes #1819)#1953

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Jim1874 wants to merge 3 commits intomodelcontextprotocol:mainfrom
Jim1874:fix/1819-v1x-listchanged
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fix(server): disable listChanged capability in V1x protocol mode (closes #1819)#1953
Jim1874 wants to merge 3 commits intomodelcontextprotocol:mainfrom
Jim1874:fix/1819-v1x-listchanged

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@Jim1874 Jim1874 commented Apr 24, 2026

Fix: Disable listChanged capability in V1x protocol mode

Problem

The server advertises listChanged capability for tools, resources, and prompts by default, even in V1x protocol mode. However, the V1x MCP protocol specification does not support the listChanged capability.

Solution

  1. Add V1X_PROTOCOL_VERSIONS constant (2024-11-05, 2024-10-07)
  2. Add isV1ProtocolVersion() helper
  3. Add stripListChangedFromCapabilities() method to remove listChanged from tools, resources, and prompts
  4. Modify _oninitialize to use stripListChangedFromCapabilities() when protocol version is V1x

Changes

  • packages/server/src/server/server.ts

Testing

All 422 integration tests pass.

Closes #1819

@Jim1874 Jim1874 requested a review from a team as a code owner April 24, 2026 02:06
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changeset-bot Bot commented Apr 24, 2026

🦋 Changeset detected

Latest commit: b209d21

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 6 packages
Name Type
@modelcontextprotocol/client Patch
@modelcontextprotocol/server Patch
@modelcontextprotocol/express Patch
@modelcontextprotocol/fastify Patch
@modelcontextprotocol/hono Patch
@modelcontextprotocol/node Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

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pkg-pr-new Bot commented Apr 24, 2026

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@modelcontextprotocol/client

npm i https://pkg.pr.new/@modelcontextprotocol/client@1953

@modelcontextprotocol/server

npm i https://pkg.pr.new/@modelcontextprotocol/server@1953

@modelcontextprotocol/express

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@modelcontextprotocol/fastify

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@modelcontextprotocol/hono

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@modelcontextprotocol/node

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commit: b209d21

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Resources: Disable listChanged capability in V1x

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