[SameRainbows]

Problem

Fixes #3103.

In packages/server/src/server/mcp.ts, _createRegisteredResource and _createRegisteredResourceTemplate synchronized title into metadata.title when updates.title !== undefined. However, when updating metadata alone without an explicit updates.title:

• If updates.metadata.title is defined, registeredResource.title was not updated and remained stale.
• If updates.metadata omitted title, the existing title in metadata was replaced, causing resources/list and resources/templates/list (which spread ...resource.metadata) to drop the title.

Solution

In _createRegisteredResource and _createRegisteredResourceTemplate:

• When updates.metadata.title is defined, synchronize it to title.
• When updates.metadata omits title but title exists on the registered item, preserve the existing title in metadata.
• Retain existing precedence where an explicit updates.title wins.

Testing

Added unit tests in packages/server/test/server/resourceMetadataTitleSync.test.ts covering:

1. registeredResource.update metadata-only update preserving top-level title.
2. registeredResource.update metadata update with new title synchronizing to top-level title.
3. registeredResourceTemplate.update metadata-only update preserving template title.
4. registeredResourceTemplate.update metadata update with new title synchronizing to template title.

Included patch changeset for @modelcontextprotocol/server.

[changeset-bot]

🦋 Changeset detected

Latest commit: d87854d

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

This PR includes changesets to release 6 packages

Name	Type
@modelcontextprotocol/server	Patch
@modelcontextprotocol/client	Patch
@modelcontextprotocol/codemod	Patch
@modelcontextprotocol/core	Patch
@modelcontextprotocol/server-legacy	Patch
@modelcontextprotocol/core-internal	Patch

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commit: d87854d