Claude Code 2.1.257 Released: Defaults to Fable 5.1
ClaudeCodeLog · x · 2026-09-02
Claude Code CLI 2.1.257 is released with the following highlights:
- Default Fable model switched to Claude Fable 5.1 (1M context), priced at $10/$50 per Mtok with $0.25/Mtok cache reads.
- Added "Time format" and timeZone settings.
- Auto mode now includes a Containment Escape rule to block auto-approval of cloud metadata fetches, egress evasion, and cross-tenant reach.
- Added CLAUDECODESUBAGENTMODELFORCE environment variable.
- Removed several legacy environment variables and models.
Related event: Anthropic Releases Fable 5.1 and Mythos 5.1 with 75% Cheaper Caching(174 posts)→
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