The HTTP 202 Accepted response is used to accept a task for background processing, and optionally providing a separate URL for monitoring the progress of the task. All answers and posts I've read about it basically suggest everyone to invent their own response types for the submission and monitoring endpoints.
Does there exist any specifications / proposals / conventions (followed by multiple companies) as to how the monitoring URL is returned (an HTTP header or response payload) or what the structure of the monitoring API response is?
Failing that, does any big names (Google, Twitter, etc) implement this pattern in their public APIs, from which to gain insight?