/fast
A Claude Code slash command, read out of the shipped bundle. No mined inventory carries it: everything below comes from what this site has written about it.
What it is
Toggle [fast mode](/docs/en/fast-mode) on or off. Availability in non-interactive mode with -p is limited; see [Toggle fast mode](/docs/en/fast-mode#toggle-fast-mode). Requires Claude Code v2.1.205 or later
Anthropic's own wording. Read off Commands, captured 2026-08-28.
Presence across releases
The miner has never read a build containing this name. It is here because a changelog entry of ours names it, which is evidence that it existed and not evidence of which releases carried it. The inventory starts at v2.1.138 and everything older than that was never mined.
Changelog entries naming it
-
v2.1.248Auto mode can be switched off server-side when /fast is on
Auto mode can be disabled server-side while /fast is on, but nothing sets that today.
named in this entry
Documentation pages
- Commands reference table Claude Code CLI
- choosing-a-model mentions it Claude Developer Platform
- Or, for the model with the same capabilities and no access approval requirement: mentions it Claude Developer Platform
- pricing mentions it Claude Developer Platform
- rate-limits mentions it Claude Developer Platform
- Message Batches API mentions it Claude Developer Platform
- fast-mode mentions it Claude Developer Platform
- Request 2 caches its request content (not the response) mentions it Claude Developer Platform
- api-and-data-retention mentions it Claude Developer Platform
- First request mentions it Claude Developer Platform
- agent-setup mentions it Claude Developer Platform
- Opus migration mentions it Claude Developer Platform
- overview mentions it Claude Developer Platform
A reference table page is one whose own table defines this name, and it is where the description above came from. A page that mentions it carries the name somewhere in its text and may say nothing about it at all. Every page carrying it.
Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the slash command does. All slash commands.