What
Auto mode is a permission mode that lets Claude Code decide on more actions without asking you each time. When a request to switch to it fails, the result now includes a code field naming the reason. Examples include auto_mode_fast_mode and auto_mode_model. If there is no more specific reason, the code is auto_mode_unavailable.
Why
A program that asks Claude Code to switch modes can now tell why the switch failed without parsing an error message. It can then react, or explain the failure to you.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The finding does not say which interface returns this result.