Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.274 ·

MCP tool descriptions carry provenance ('source') into the render payload

MCP tool data sent to the UI now includes where each MCP client came from

TierUnder the hoodhow much it should matter to you
Useful1my rating, 1 to 5
Signal1worth watching, 1 to 5
AreaMCPwhat it touches
KindInternal Changesin v2.1.274,
Under the hood

MCP tool data sent to the UI now includes where each MCP client came from

What

When Claude Code passes information about connected MCP clients (Model Context Protocol servers providing extra tools) into the data used to render the interface, each client entry now includes a source field alongside its name and type, computed by a new internal helper.

Why

This adds provenance information about MCP tools that the interface (or other consumers of this data) can use, though the finding doesn't specify what visibly changes for users yet.

How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtIt's unclear whether or how this source information is currently surfaced to the user in the interface.

See this entry in the whole of v2.1.274 →