Activating 'Reasoning summary' with o4-mini

API
1

I am getting a ‘Bad request’ error with this attempt to activate the reasoning summary with setting in C# the summary = auto, which is according to the API reference.

// Add reasoning parameters
requestBody.reasoning = new
{
effort = “medium”, // Options: “low”, “medium”, “high”
summary = “auto” // Options: “auto”, “concise”, “detailed”
};

If I Ieave away the line for the summary, the API works fine:

// Add reasoning parameters
requestBody.reasoning = new
{
effort = “medium” // Options: “low”, “medium”, “high”
};

What do I do wrong here?

2

Have you verified your organization? If so, which API are you having difficulties with (responses or completions)?