---
title: "429 Too Many Requests defined | Agent Ready Checklist"
description: "429 Too Many Requests: Status code for throttling, defined in RFC 6585, optionally with Retry-After. AgentReady wants it in place of a challenge page."
canonical: https://agentreadychecklist.com/glossary/429-too-many-requests
site: "Agent Ready Checklist"
last_updated: 2026-11-05
section: "Glossary"
---

# 429 Too Many Requests defined | Agent Ready Checklist

> 429 Too Many Requests: Status code for throttling, defined in RFC 6585, optionally with Retry-After. AgentReady wants it in place of a challenge page.

Source: https://agentreadychecklist.com/glossary/429-too-many-requests
Site: Agent Ready Checklist
Last reviewed: 2026-11-05
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# 429 Too Many Requests

Status code for throttling, defined in RFC 6585, optionally with Retry-After. AgentReady wants it in place of a challenge page. Example: HTTP/1.1 429 Too Many Requests Retry-After: 30 Content-Type: text/plain. RFC 6585 defines 429 Too Many Requests and allows a Retry-After header telling the client how long to wait.

## Definition

Status code for throttling, defined in RFC 6585, optionally with Retry-After. AgentReady wants it in place of a challenge page.

## Example

```text
HTTP/1.1 429 Too Many Requests
Retry-After: 30
Content-Type: text/plain
```

## Nearby terms

-   [Retry-After](https://agentreadychecklist.com/glossary/retry-after/)Response header telling a client how many seconds (or until what date) to wait before retrying.

## Asked about it

### What should my rate limiter return to agents?

A 429 Too Many Requests with a Retry-After header, not a CAPTCHA or challenge page. Agents and crawlers treat 429 as a back-off signal and come back; a challenge page looks like content or a block.

## Sources

-   [rfc-editor.org/rfc/rfc6585](https://www.rfc-editor.org/rfc/rfc6585)read 2026-11-04
-   [github.com/agentready-org/standard/blob/main/spec/spec.md](https://github.com/agentready-org/standard/blob/main/spec/spec.md)read 2026-11-04

Last reviewed 2026-11-05. AgentReady v2.0, read 2026-11-04.