You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
Tool CallsArea: what it touches
ImprovementsKind: in v2.1.282,
ImprovementsSection of the release
What
Claude does its work by calling tools, such as reading a file or running a command, and each call must fill in the tool's inputs in the expected shape. When it gets them wrong, Claude Code sends back an error explaining what is wrong.
That error used to explain only missing inputs, unexpected inputs and inputs of the wrong type. Anything else came through as raw technical text. Now:
Other problems get a plain explanation, for example that a given input is invalid, or that it matches none of the accepted forms.
The number of these extra lines is limited, followed by a count of how many more issues were not listed.
Unexpected inputs are reported with their full location inside nested inputs.
A problem with no message no longer causes the error formatting itself to fail.
Why
Clearer error text helps Claude fix a malformed tool call on the next attempt, which should mean fewer rounds of failed retries.
