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Anthropic’s Claude Fable 5 (model ID

2026-06-09 · 17:24 UTC ·@vercel_dev ·0 min read

Brief

Anthropic’s new Claude Fable 5 — identified as 'anthropic/claude-fable-5' and labeled a Mythos-class model — has been added to Vercel’s AI Gateway (announcement dated 2026-06-09). Vercel and Anthropic claim the model outperforms prior publicly available Claude models and has been made safe for general use; the post links to Vercel’s changelog for details.

Why it matters

Anthropic’s Claude Fable 5 (model ID: 'anthropic/claude-fable-5') is now available via Vercel’s AI Gateway as of the June 9, 2026 announcement.

Key details

  • Vercel and Anthropic describe Claude Fable 5 as a 'Mythos-class' model, claimed to exceed capabilities of any previously generally available Claude model and to be made 'safe for general use'.
  • Announcement includes a Vercel changelog link (vercel.com/changelog/claude-…) and a promotional post from Claude’s official account.
Source evidence

Claude Fable 5 is now on AI Gateway.

A Mythos-class model for your hardest unsolved problems.

𝚖𝚘𝚍𝚎𝚕: '𝚊𝚗𝚝𝚑𝚛𝚘𝚙𝚒𝚌/𝚌𝚕𝚊𝚞𝚍𝚎-𝚏𝚊𝚋𝚕𝚎-𝟻'

vercel.com/changelog/claude-…

Claude (@claudeai)

Introducing Claude Fable 5: a Mythos-class model that we’ve made safe for general use.

Its capabilities exceed those of any model we’ve ever made generally available.

Video

— https://nitter.net/claudeai/status/2064394146916229443#m