Source Intelligence

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

All of v2.1.248 Home All releases olderv2.1.247 v2.1.250newer
Claude Code v2.1.248

Auto mode can be switched off server-side when /fast is on

Not switched on
Useful2 Signal3
Auto Mode

Auto mode can be disabled server-side while /fast is on, but nothing sets that today.

A disableFastMode breaker exists with no local default, so it never fires without server config.

Feature flag
tengu_auto_mode_config Not enough to say

Nothing here resolved what this flag was doing on this version, so nothing here should be read as on or off.

This account: no value returned · anonymous baseline: no value returned · compiled default in v2.1.248: not a boolean we can read

Read once, for one account on one subscription tier, against v2.1.248. It isn't a statement about your account. What a flag value here can and cannot tell you

/fast
What

A new circuit breaker disables auto mode with the reason "fast-mode" when the remote tengu_auto_mode_config object sets disableFastMode and you have /fast toggled on. There is no local fallback value for disableFastMode, so with no server config it is undefined and the breaker never fires. This replaces the old branch that blocked auto mode for providers lacking an opt-in.

Details
  • The debug output now reports a disableFastModeBreakerFires counter.
Evidence

auto mode disabled: tengu_auto_mode_config.disableFastMode with the /fast toggle on

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

Related

Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.

See this entry in the whole of v2.1.248 →