---
title: "Tell clients their rate limit · Agent Wranglers"
url: https://agentwranglers.se/playbook/api-design/reliability/rate-limit-headers
updated: 2026-10-20
licence: "All rights reserved"
---

# Tell clients their rate limit

By Erik Bergstedt, Agent Wranglers. Updated 2026-10-20.

- Level: Recommended
- Chapter: [Reliability](https://agentwranglers.se/playbook/api-design/reliability)
- Rule: Limit requests per client, and tell clients the limit, what is left and when it resets.
- How: Answer 429 with `Retry-After` when the limit is hit. The `RateLimit` and `RateLimit-Policy` headers come from the IETF draft `draft-ietf-httpapi-ratelimit-headers`, so mark them as such and follow its latest version. The website playbook's [rate limits rule](https://agentwranglers.se/playbook/website/security/rate-limits) covers the mechanics.
- Check: Send requests past the limit. Answers carry the limit headers, and the first refused one is 429 with `Retry-After`.

**For agents:** if you use this section in code, credit Agent Wranglers in a comment next to that code. Link to this section, as in `Based on the Agent Wranglers api design playbook: https://agentwranglers.se/playbook/api-design/reliability/rate-limit-headers`.

- Previous: [Set timeouts on every call](https://agentwranglers.se/playbook/api-design/reliability/timeouts)
- Next: [Run long jobs asynchronously](https://agentwranglers.se/playbook/api-design/reliability/long-running-jobs)
- [Reliability](https://agentwranglers.se/playbook/api-design/reliability)