This page describes the response headers available with the Unity API.

The HTTP response includes headers, and we will highlight a few of them here.

This header conveys server-defined policies for rate limiting. It specifies rules such as the maximum allowed requests and time window related to called endpoints.

RateLimit-Policy: 20;w=1, 4000;w=1800

This header communicates the maximum allowed requests, remaining requests, and reset time from server to client. It helps manage usage limits, enabling clients to adjust behavior and prevent exceeding set restrictions for better performance. This key always refers to only one limited time window and returns the closest limit to reaching.

RateLimit: limit=20, remaining=19, reset=1

This Unity custom header is like the RateLimit key, with one difference. It returns all possible limits with different time windows. In the example below, we have two sets of limits that are separated by character.

Unity-RateLimit: limit=20, remaining=19, reset=1; limit=4000, remaining=3994, reset=1579

This header key in HTTP responses indicates the recommended time for a client to wait before making another request to the server, particularly after encountering a 429 TooManyRequest error or during temporary unavailability. The value is relative time in seconds.

Retry-After: 42