Create a Message changedapi/beta/messages/create
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Lines−87removed
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3,906
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39063906
39073907- `temperature: optional number`
39083908
3909 **Deprecated**: Deprecated. Models released after Claude Opus 4.6 do not support setting temperature. A value of 1.0 of will be accepted for backwards compatibility, all other values will be rejected with a 400 error.
3909 **Deprecated**: Deprecated. Models released after Claude Opus 4.6 do not support setting temperature. A value of 1.0 will be accepted for backwards compatibility, all other values will be rejected with a 400 error.
39103910
39113911 Amount of randomness injected into the response.
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from line 5397
53975397
53985398 minimum: 0
53995399
5400 - `model: Model`
5400 - `model: Model or null`
54015401
54025402 The model that will complete your prompt.
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from line 5495
54955495
54965496 Token usage for the fallback-model attempt of a server-side fallback request.
54975497
5498 Produced in place of a `message` entry for whichever hop served the
5499 response. A declined hop produces the existing `message` entry. Whether
5500 a fallback model served the response is signalled by the presence of this
5501 entry in `usage.iterations`.
5498 The terminal entry of a fallback-served turn: when a fallback hop's
5499 output is the returned message, the entry for the iteration that
5500 completed it carries this type in place of `message`. A declined hop
5501 and the serving hop's earlier tool-loop iterations produce `message`
5502 entries. Whether a fallback model served the response is signalled by
5503 the presence of this entry in `usage.iterations`.
55025504
55035505 - `type: "fallback_message"`
55045506
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