API model ID
The exact string you pass to an API to select a model, which can differ between the maker's API and cloud platforms.
Why it matters. Pin specific IDs in production so behavior and price don't change under you.
How it works
The API model ID is the exact identifier you pass in a request to choose a model. The same model can have different IDs on the maker's own API and on cloud platforms, and makers sometimes publish both a dated snapshot ID and a shorter alias.
An alias may be moved to a newer snapshot over time, while a dated ID stays fixed until the model is retired. Cloud platforms may add region prefixes or version suffixes. This site lists the maker's API ID and, where known, platform IDs.
Pin a dated ID in production so behavior and price change only when you choose. Keep the ID in configuration, not scattered through code, so a migration is one change.
Worked example
Illustrative: a team uses an alias such as 'model-latest' in production. The maker points the alias at a new snapshot, its output formatting changes slightly, and a parser breaks overnight. A pinned ID such as 'model-2026-05-14' would have kept the old behavior until the team tested the new one.
Common mistakes
- Using an alias in production and getting a different model without warning.
- Copying the maker's ID into a cloud platform call where the ID format differs.
- Hard-coding IDs across many files, which makes retirements painful.
See it on a real card: Build with it on Claude Opus 5.5.