Model family / anthropic-claude-opus
Claude Opus
Resolved to Claude Opus 5 5 20260921. Pin the exact model and route below; provider aliases remain moving targets.
- Exact pin
- anthropic/claude-opus-5.5-20260921 anthropic/claude-opus-5.5-20260921
- Ordering basis
- source catalog listed at Catalog listed-at, not vendor release date
- Moving aliases
- 1 Provider routes, never an exact pin
- Candidates considered
- 2 Current source-backed releases
Agent-safe resolution
Pin this concrete route
Use the model canonical slug for reproducibility; use the provider model ID only on the displayed provider route.
- Canonical model
anthropic/claude-opus-5.5-20260921- Provider route
anthropic/claude-opus-5.5-20260921- Evidence retrieved
Evidence ledger
Current concrete releases
Concrete releases are immutable identities. The displayed ordering basis is retained with each source fact.
Claude Opus 5 5 20260921
stable · standardsource catalog listed at · Sep 22, 2026, 04:32 PM UTCanthropic/claude-opus-5.5-20260921anthropic/claude-opus-5.5-20260921Claude Opus 5 20260723
stable · standardsource catalog listed at · Jul 24, 2026, 05:02 PM UTCanthropic/claude-opus-5-20260723anthropic/claude-opus-5-20260723Mutable provider routes
Observed aliases
These routes are explicitly separate from the exact pin. Their source-run resolution history remains available through the public API.
~anthropic/claude-opus-latest→ family latest