You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
Context WindowArea: what it touches
ImprovementsKind: in v2.1.307,
ImprovementsSection of the release
Unclear Whether a model name ending in [1m] still gives a larger window is not settled.
What
The context window is how much text a model can take in at once. Claude Code now sets it to the smaller of two numbers: the window the model states and a window set for each model. A separate value is kept for when you have not opted into a larger window. The old fixed cap was removed.
Model names ending in [1m] are no longer handled specially when Claude Code reads model names, follows aliases, or deals with retired models.
Why
This may change how much context you get with a given model and when compaction starts. Compaction is when Claude Code summarises older parts of the conversation to free up room.
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtWhether a model name ending in `[1m]` still gives a larger window is not settled.
Anthropic's release notes agreeFixed requests failing with a model-not-found error when CLAUDE_CODE_DISABLE_1M_CONTEXT is set and the model is an alias with the [1m]…
