Claude Code v2.1.169 → v2.1.170: Claude Fable 5 now generally available

[claude-yolo]

WHY this matters

🚀 Claude Fable 5 is the headline: a Mythos-class model made safe for general use. Anthropic calls it "capabilities exceed those of any model we've ever made generally available." This is a big deal for Claude Code users — update to v2.1.170 to access it.

Also ships: server-side fallback API (server-side-fallback-2026-06-01 beta flag) enabling model fallback chains server-side.

Bug fixes worth noting:

• Fixed VS Code integrated terminal not saving transcripts / not appearing in --resume

What changed in the docs

• CHANGELOG updated with v2.1.170 release notes
• New API docs for server-side fallback (content/en/build-with-claude/refusals-and-fallback.md, fallback-credit.md)
• Updated model reference docs across platform + agent APIs

Links

• PR: docs: Claude Code v2.1.170 - Claude Fable 5 + Mythos 5 launch, server-side fallback API claude-code-docs#1028
• Anthropic announcement: https://www.anthropic.com/news/claude-fable-5-mythos-5