You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
SDKArea: what it touches
ImprovementsKind: in v2.1.319,
ImprovementsSection of the release
What
The SDK is the toolkit for building programs on top of Claude Code. Several things it reports are different:
Task progress updates now include usage_limit_wait, with the time the limit resets, when a task is waiting on a usage limit.
Errors from MCP tools, which are tools provided by outside programs, now carry an error_code, taken from a code the server puts in the result's _meta field.
Task results can now include content that is not text.
Why
Programs built on the SDK can show that a task is paused by a usage limit and when it will continue, and can react to specific MCP errors by their code.
