--autocompact
A Claude Code CLI flag, 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
Set the [auto-compact window](/docs/en/model-config#set-the-auto-compact-window) for this session without changing your saved settings. Accepts the same values as /autocompact; that section covers the value forms and what overrides the flag. Requires Claude Code v2.1.221 or later
Anthropic's own wording. Read off CLI reference, 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
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v2.1.221/autocompact ungated, plus an --autocompact CLI option
You can now set when auto-compaction kicks in with a new --autocompact flag, and /autocompact works for everyone.
named in this entry
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v2.1.221New --autocompact flag for the auto-compact window
You can set the auto-compact window at launch with --autocompact, using auto or 100k to 1M.
named in this entry
Documentation pages
- CLI reference reference table Claude Code CLI
- Environment variables mentions it Claude Code CLI
- Model configuration mentions it Claude Code CLI
- Claude Code settings mentions it Claude Code CLI
- Claude Code settings reference mentions it Claude Code CLI
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 CLI flag does. All CLI flags.