Solution from How to manage prompt/context complexity v. 504 Deadline - #2 by sps.
Suggestion: this question could have been answered proactively by adding a reference to the “timeout” parameter to the text of the 504 error message. When I was a product manager, I always made a review of error messages an early priority, since edits are a virtually zero-cost way to impact the user at “point of distress”. OpenAI does this a lot, I’ve noticed. @Logan_Kilpatrick