The undated form of a release-pinned model id, e.g. claude-opus-5-20260401 → claude-opus-5. Returns undefined when the id carries no date suffix.
claude-opus-5-20260401
claude-opus-5
undefined
The undated form of a release-pinned model id, e.g.
claude-opus-5-20260401→claude-opus-5. Returnsundefinedwhen the id carries no date suffix.