Last updated: 2026-10-30

What is Model pinning?

Specifying an exact model ID instead of a floating alias, so behaviour does not change under you when a provider updates the alias. Anthropic says every Claude model ID is a pinned snapshot, including the dateless IDs such as `claude-opus-5-5`; other providers' aliases can float, so check their docs. Pin anything running in production.

See also

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