Does Responses API support `stop` parameter or not?
OpenAI Developer Community
April 28, 2026
To my understanding, this article says that Responses API supports the stop parameter.
https://help.openai.com/en/articles/5072518-controlling-the-length-of-openai-model-responses
However, when I tried sending a request with stop parameter, I received the following error response.
{
"error": {
"message": "Unknown parameter: 'stop'. Did you mean 'store'?",
"type": "invalid_request_error",
"param": "stop",
"code": "unknown_parameter"
}
}
And I can’t find any information regarding stop parameter either in the Responses API reference or in the migration guide.
OpenAI API Reference
Create a model response
developers.openai.com
Migrate to the Responses API | OpenAI API
Is the stop parameter not supported in Responses API?
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