A Claude Code environment variable, read out of the shipped bundle.
It has been in the build since v2.1.223, including the newest one read.
Set to 1 to skip proactive auto-compaction when Claude Code doesn't recognize the model ID, such as an LLM gateway alias. Without this variable, Claude Code compacts at the context window it assumes for the ID. CLAUDE_CODE_MAX_CONTEXT_TOKENS can correct the assumed window instead; see Correct the window for a gateway or custom model ID for when each variable applies. Requires Claude Code v2.1.223 or later
Unknown model names now get an assumed context budget so auto-compact works instead of stalling.
named in this entry, found in this entry's text
First cited
3
The earliest release whose published evidence quoted CLAUDE_CODE_DISABLE_UNKNOWN_MODEL_WINDOW_ENFORCEMENT was v2.1.223, 5 Aug 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table below.
ReleaseDateThe span that was quoted
v2.1.2235 Aug 2026CLAUDE_CODE_DISABLE_UNKNOWN_MODEL_WINDOW_ENFORCEMENT
v2.1.2235 Aug 2026CLAUDE_CODE_DISABLE_UNKNOWN_MODEL_WINDOW_ENFORCEMENT=1 restores the previous wait-for-the-API behavior.
v2.1.2571 Sep 2026CLAUDE_CODE_DISABLE_UNKNOWN_MODEL_WINDOW_ENFORCEMENT=1 restores the previous wait-for-the-API behavior
Presence across releases
1
BuildsHow manyDatesReading
v2.1.223 – v2.1.30874 builds5 Aug 2026 → 22 Oct 2026 ◆in the build
Build by build
74
One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
v2.1.29914 Oct 2026·presentverdict: present · bool
v2.1.30014 Oct 2026·presentverdict: present · bool
v2.1.30115 Oct 2026·presentverdict: present · bool
v2.1.30216 Oct 2026·presentverdict: present · bool
v2.1.30318 Oct 2026·presentverdict: present · bool
v2.1.30419 Oct 2026·presentverdict: present · bool
v2.1.30520 Oct 2026·presentverdict: present · bool
v2.1.30621 Oct 2026·presentverdict: present · bool
v2.1.30721 Oct 2026·presentverdict: present · bool
v2.1.30822 Oct 2026·presentverdict: present · bool
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 environment variable does. All environment variables.
