You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
SDKArea: what it touches
ImprovementsKind: in v2.1.318,
ImprovementsSection of the release
What
Claude Code keeps settings in config files written in JSON, a text format. When one read at startup is not valid JSON:
Claude Code prints extra advice beyond the old "Configuration error in" line, and records config_file_invalid as the reason it stopped.
The file is left unchanged: saves to it are dropped rather than overwriting it.
config_file_invalid is a new startup-refusal code in the SDK schema, the description of messages for programs that embed Claude Code. Every start without a terminal is refused until the file is repaired.
Why
A corrupt config is no longer overwritten, so you can still repair it and keep your settings. Programs that run Claude Code automatically can now tell this case apart from a failure that is worth retrying, and know to fix the file first.
