Follow Discord
Sweep 22 Sep 2026 · 17:19Z Build v2.1.280 501 read Stable v2.1.267 Latest v2.1.280 Next v2.1.280 Feeds RSS JSON llms.txt Unofficial
Home Docs Claude Developer Platform 1 Sep 2026
One change · api

overview changed

models/mythos-5-1/overview

Nearest release: v2.1.258, published an hour after this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.

Recorded here
Lines+1added
Lines−1removed
From line 12 where the diff opens
First seen 1 Sep 2026 this site's first read of the page
Recorded edits4to this page, all time

The whole hunk

from line 12, old and new numbered
/
lines
from line 12
1212 
1313Context window: 1M tokens · Max output: 128K tokens · Input pricing: $10 / MTok · Output pricing: $50 / MTok
1414 
15[Announcement](https://www.anthropic.com/claude/fable/5-1) · [What’s new](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1) · [Migration guide](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-mythos-5-to-claude-mythos-5-1)
15[Announcement](https://www.anthropic.com/claude-fable-and-mythos-5-1) · [What’s new](https://platform.claude.com/docs/en/models/fable-5-1/whats-new-fable-5-1) · [Migration guide](https://platform.claude.com/docs/en/models/fable-5-1/migration-guide#migrating-from-claude-mythos-5-to-claude-mythos-5-1)
1616 
1717Claude Mythos 5.1 is offered separately, by invitation only, as part of Project Glasswing. It shares Claude Fable 5.1’s specifications and pricing. For access, contact your Anthropic, AWS, or Google Cloud account team. [See Claude Fable 5.1](https://platform.claude.com/docs/en/models/fable-5-1/overview) · [Project Glasswing](https://anthropic.com/glasswing)
1818