You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
MCPArea: what it touches
ImprovementsKind: in v2.1.312,
ImprovementsSection of the release
What
An MCP tool is a tool provided through an MCP server, a connector that gives Claude extra tools. When Claude Code builds the answer to an MCP tool call, it now tries each possible form of the result one at a time. It returns the first form that fits the size limit. If one form fails to build, Claude Code logs the failure and moves on to a smaller form.
It reports result_too_large only when no form fits. Before, any error while building the result failed the whole call with result_unbuildable.
Why
A problem with one form of the result no longer throws away the whole MCP tool result.
