Is claude-mythos-5-1 deprecated?

Q: Is claude-mythos-5-1 deprecated?

Not yet, but retirement is scheduled. Sunset scheduled for 2027-09-01, reported by a third-party catalog. The identifier still resolves today.

RETIRING IN 356 DAYS

Sunset scheduled for 2027-09-01, reported by a third-party catalog. The identifier still resolves today.

state=dying sunset=2027-09-01 days_remaining=356 severity=high sources=litellm evidence_tier=catalog confirmed_by_endpoint=false documented_by_provider=false replacement=none corroborated=single-source divergent_fields=none checked=2026-09-10 14:50Z

anthropic/claude-mythos-5-1

Vendor: anthropic. Tracked by 1 of 5 sources.

What each source reports

**endpoint** = the provider's own machine-readable API, the strongest evidence. **provider docs** = the provider's own documentation, read by a model — first-party content, inferred reading. Unlabelled rows are third-party catalogs. Where sources disagree both values are shown rather than silently reconciled.
Source	ID	Context	Max out	In $/Mtok	Out $/Mtok	Sunset
litellm	claude-mythos-5-1	1,000,000	128,000	$10	$50	2027-09-01

Change history

Severity	Change	What	Detected
low	added	new model claude-mythos-5-1 (1,000,000 ctx)	2026-09-06
medium	deprecated	claude-mythos-5-1: retires 2027-09-01 (in 360 days)	2026-09-06