Models: Fable 5 and Mythos 5 returned on 2026-07-01 (the directive was lifted on 06-30). Fable 5 is included in paid plans up to 50% of weekly limits only through 07-07, then via usage credits; strengthened safeguards.
New Sonnet 5: default model on Free and Pro, 1M context window in chat too, introductory API pricing through 2026-08-31.
Ecosystem: Claude Science arrives (scientific research, beta on macOS/Linux) along with @Claude / Claude Tag (tag Claude in Slack, beta for Team/Enterprise).
Chapters F.2, F.3 and L6.4 updated, along with the facts ledger.
Rev. 2 · 2026-06-27
Volatile data updated and a new site
Models: Fable 5 and Mythos 5 are suspended (a US government export control directive dated 2026-06-12). The manual flags this.
Context window: 500K tokens in chat for the top models, 200K for the others, up to 1M in Claude Code.
Cowork: status updated (macOS/Windows, paid plans) and the permission modes added.
Site: dark theme, 33 chapters online, sharing, a mini-tool and a full English edition.
Rev. 1 · 2026-06-22
First complete edition
33 chapters across six levels: from the basics to Skills, MCP, automation and the API.