You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
SDKArea: what it touches
ImprovementsKind: in v2.1.301,
ImprovementsSection of the release
Unclear Only the request's description mentions result_not_for_model; whether requests already accept it is not confirmed.
What
mcp_call is a request a program controlling Claude Code can send to call a tool on an MCP server (an add-on that provides tools) directly. Its description used to say the result always goes through the same processing as when Claude itself calls the tool. It now says this happens unless result_not_for_model is set.
Why
A program making these calls has an option to get a result that is not prepared for Claude to read.
Read from
Names in the bundlemcp_callresult_not_for_model
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 doubtOnly the request's description mentions result_not_for_model; whether requests already accept it is not confirmed.
