Nov 9, 2026 · found Nov 9, 2026, 12:30 PM PT
Anthropic releases Claude Fable 5.2 and Mythos 5.2
Verdict: Vendor-reported · Model releases · Agents and coding · AI security
The release is real and priced at $8/$40 per million tokens, but every benchmark in the post is Anthropic's own and no independent index has scored Fable 5.2 yet.
Anthropic released Claude Fable 5.2 and Claude Mythos 5.2 on 9 November, the same model with different safeguards.
- Claim: Fable 5.2 scores 49.1% on FrontierCode 2.0 at Xhigh effort against 45.5% for Opus 5.5 and 42.8% for GPT-6 Astra, and 69.9% on FrontierSWE v2. Price is $8/$40 per million tokens. Anthropic
- Evidence: The post links a system card, which could not be opened here. Artificial Analysis does not yet list Fable 5.2. Artificial Analysis
- Caveats: All numbers are Anthropic’s. FrontierCode comes from Cognition, which also supplies a tester quote. CVE Rediscovery and RoboDojo are internal, and one footnote calls cyber identification roughly on par with Opus 5.5. Anthropic
- Why it matters: Mythos stays behind verification programs. The 1,000-subagent operating-system demo is a single anecdote. Anthropic
Verdict history
- Nov 9, 2026, 12:30 PM PT: Vendor-reported. Primary post read (found through the newsroom listing; the system card page did not open). Artificial Analysis leaderboard checked at 20:30 UTC and lists only Fable 5.1, so no independent score yet. Recheck for an AA index and FrontierCode entry.