Chat

Update chat completion

Modify a stored chat completion. Only Chat Completions that have been created with the store parameter set to true can be modified. Currently, the only supported modification is to update the metadata field.

post/chat/completions/{completion_id}

Path parameters

completion_idstring required

The ID of the chat completion to update.

Request body

metadataMetadata nullable required

Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format, and querying for objects via API or the dashboard.

Keys are strings with a maximum length of 64 characters. Values are strings with a maximum length of 512 characters.

Response

A chat completion

idstring required

A unique identifier for the chat completion.

createdinteger required

The Unix timestamp (in seconds) of when the chat completion was created.

modelstring required

The model used for the chat completion.

metadataMetadata nullable

Keys are strings with a maximum length of 64 characters. Values are strings with a maximum length of 512 characters.

Specifies the processing type used for serving the request.

If set to 'auto', then the request will be processed with the service tier configured in the Project settings. Unless otherwise configured, the Project will use 'default'.
If set to 'default', then the request will be processed with the standard pricing and performance for the selected model.
If set to 'flex', then the request will be processed with the Flex Processing service tier.
To opt-in to Fast mode at the request level, include the service_tier=fast or service_tier=priority parameter for Responses or Chat Completions. The response will show service_tier=priority regardless of if you specify service_tier=fast or priority in your request.
When not set, the default behavior is 'auto'.

When the service_tier parameter is set, the response body will include the service_tier value based on the processing mode actually used to serve the request. This response value may be different from the value set in the parameter.

system_fingerprintstring

This fingerprint represents the backend configuration that the model runs with.

Can be used in conjunction with the seed request parameter to understand when backend changes have been made that might impact determinism.

object'chat.completion' required

The object type, which is always chat.completion.

Changes

Changed in 9 of the 163 revisions of this API.17423

Sep 25, 20268166b02050674See the full diff
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Sep 1, 2026ca86486f9fef1See the full diff
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Aug 27, 202660c5936f2a2f1See the full diff
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Aug 14, 20269080adae100c1See the full diff
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  added the optional property to the response with the status
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Aug 14, 2026fe3335711e483See the full diff
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Aug 5, 2026ab0c5306e39012See the full diff
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This revision also has 2 changes that name no endpoint, such as unreferenced schemas being removed. See the revision's changelog
May 13, 202674cbcf73838f179See the full diff
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  the request property became not nullable
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  response property choices/items/message/content list-of-types was widened by adding types null to media type application/json of response 200
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  response property choices/items/message/refusal list-of-types was widened by adding types null to media type application/json of response 200
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  response property service_tier list-of-types was widened by adding types null to media type application/json of response 200
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  request property list-of-types was widened by adding types null to media type application/json
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  added subschema #1 subschema #2 to the // response property anyOf list for the response status
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  added subschema #1 subschema #2 to the /// response property anyOf list for the response status
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  the response's property default value auto was removed for the status
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  response property system_fingerprint deprecated
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  added discriminator to //// response property for the response status
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  removed the auto enum value from the response property for the response status
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  removed the default enum value from the response property for the response status
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  removed the flex enum value from the response property for the response status
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This revision also has 40 changes that name no endpoint, such as unreferenced schemas being removed. See the revision's changelog
Apr 29, 20256a6c681b182022See the full diff
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  added the new auto enum value to the response property for the response status
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  added the new flex enum value to the response property for the response status
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  the response's property default value auto was added for the status
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  removed the scale enum value from the response property for the response status
  response-property-enum-value-removed
This revision also has 18 changes that name no endpoint, such as unreferenced schemas being removed. See the revision's changelog
Mar 11, 20256ab43fe7798e1See the full diff
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  endpoint added
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Full history