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Does Responses API support `stop` parameter or not?

OpenAI Developer Community April 28, 2026
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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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