{"id":"clm_75AE3DDB40F4","entity":"anthropic","predicate":"released","value":"Claude Fable 5","value_json":{"feed":"claude-platform-release-notes","item":"https://platform.claude.com/docs/en/release-notes/overview#2026-06-09","tags":{"v":2,"ai":true,"by":"claude-haiku-5-5","on":"2026-10-31","themes":["reasoning"],"model_tier":"frontier","release_kind":"model"},"check":{"on":"2026-10-31","url":"https://support.claude.com/en/articles/12138966-release-notes#2026-06-09","pages":2,"quote":"June 9, 2026 Claude Fable 5 launch We launched Claude Fable 5, a Mythos-class model that we’ve made safe for general use.","outcome":"checked"},"evidence":"We’ve launched Claude Fable 5 ( claude-fable-5 ), our most capable model open to all customers, alongside Claude Mythos 5 ( claude-mythos-5 ) for Project Glasswing participants. Both models support a 1M token context window by default, 128k max output tokens, and always-on adaptive thinking . See Cl","extracted_by":"claude-haiku-5-5","primary_source":true},"valid_from":"2026-06-09","valid_to":null,"published":"2026-06-09","recorded":"2026-10-31","confidence":0.7,"status":"valid","assertable":true,"superseded_by":null,"supersedes":[],"first_seen_at":"2026-10-31T02:13:24.022264+00:00","updated_at":"2026-10-31T03:22:07.868345+00:00","sources":[{"url":"https://support.claude.com/en/articles/12138966-release-notes#2026-06-09","tier":"primary","publisher":"Anthropic","published_at":"2026-06-09T00:00:00+00:00"},{"url":"https://platform.claude.com/docs/en/release-notes/overview#2026-06-09","tier":"primary","publisher":"Anthropic","published_at":"2026-06-09T00:00:00+00:00"}],"evidence":{"by":"page-read","on":"2026-10-31","quote":"June 9, 2026 Claude Fable 5 launch We launched Claude Fable 5, a Mythos-class model that we’ve made safe for general use.","url":"https://support.claude.com/en/articles/12138966-release-notes#2026-06-09","excerpt":"We’ve launched Claude Fable 5 ( claude-fable-5 ), our most capable model open to all customers, alongside Claude Mythos 5 ( claude-mythos-5 ) for Project Glasswing participants. Both models support a 1M token context window by default, 128k max output tokens, and always-on adaptive thinking . See Cl"},"legend":{"dates":"valid_from: when the claim took effect (a period figure: the day its period closed). published: the earliest day a source on the record published it (a filing's filing date, a post's date; null when no source carries one). recorded: the day AsOf first held it. A figure can take effect weeks before it is published.","why_not":{},"checked_by":{"page-read":"its source page states the value and the date"}}}