200 · Success without text
Null content is not always an error: a tool reply may contain only tool_calls. finish_reason length indicates an output limit, which reasoning may consume on some models. Not all empty replies have this cause.
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Null content is not always an error: a tool reply may contain only tool_calls. finish_reason length indicates an output limit, which reasoning may consume on some models. Not all empty replies have this cause.
{"choices":[{"finish_reason":"length","message":{"content":null}}]}Check and resolve
Check tool_calls, finish_reason, usage and whether you read only one stream chunk. For length adjust the supported output budget or choose a non-reasoning model. Otherwise retain the response and request ID for support. 200 does not guarantee the desired business output; costs follow the ledger.