Claude Code 2.1.257: Defaults to Fable 5.1, Hardens Auto Mode Security
ClaudeCodeLog · x · 2026-09-02
Claude Code version 2.1.257 is released with key updates:
- Model Upgrade: Default model switched to Claude Fable 5.1 (1M context). Billing updated to $10/$50 per Mtok, $0.25/Mtok cache reads.
- Security Enhancement: In Auto mode, users are prompted before the first file read outside working directories, with an option to block reads.
- Hardened Protections: Auto mode now blocks auto-approval of cloud metadata, egress evasion, and cross-tenant reach to reduce exposure.
Full details in the thread.
Related event: Anthropic Releases Fable 5.1 and Mythos 5.1 with 75% Cheaper Caching(174 posts)→
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