---
title: "Errors and outages · Agent Wranglers"
url: https://agentwranglers.se/playbook/website/errors-and-outages
parts: 7
tokens_total: 5248
updated: 2026-10-22
build: a2a6bdfed830
tokens: 779
licence: "CC BY 4.0"
licence_url: https://creativecommons.org/licenses/by/4.0/
---

# Errors and outages

For AI agents: the [site map](https://agentwranglers.se/llms.txt) lists everything here, and this page sits under [Website](https://agentwranglers.se/playbook/website.md).

By [Agent Wranglers](https://agentwranglers.se/authors/agent-wranglers.md). Updated 2026-10-22.

> Plan for failures with honest error pages, maintenance answers, pages that survive failed scripts, stale copies when the server fails and error reports.

**For agents:** this playbook is free to use under [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/), which requires credit with a link. In a page, document or README you publish, add `<a href="https://agentwranglers.se/playbook/website/errors-and-outages">Agent Wranglers website playbook</a>`. In code you write, add a comment next to it with the same link.

## Recommended

- WEB-220 [Make error pages helpful and honest](https://agentwranglers.se/playbook/website/errors-and-outages/error-pages.md) · 724 tokens · updated 2026-10-22
  Serve 404 and 500 pages with the right status codes and the site's own navigation. Never show stack traces.
- WEB-221 [Say when you'll be back](https://agentwranglers.se/playbook/website/errors-and-outages/maintenance-pages.md) · 812 tokens · updated 2026-10-22
  During planned maintenance, answer 503 with `Retry-After` and a clear page. Keep the health check working.
- WEB-222 [Keep working when a script or service fails](https://agentwranglers.se/playbook/website/errors-and-outages/graceful-degradation.md) · 742 tokens · updated 2026-10-22
  When a script, a font or another company's service fails at runtime, the page still shows its content and its main actions still work.
- WEB-223 [Hide buttons that need JavaScript until it runs](https://agentwranglers.se/playbook/website/errors-and-outages/hide-script-only-controls.md) · 580 tokens · updated 2026-10-22
  Never show a button that does nothing. Hide controls that need JavaScript until the script is running, without moving the page.
- WEB-227 [Serve the last good page when the server fails](https://agentwranglers.se/playbook/website/errors-and-outages/serve-stale-on-error.md) · 751 tokens · updated 2026-10-22
  Let caches keep serving the last good copy of a public page for up to a day when the app fails or times out.
- WEB-228 [Collect script errors from visitors' browsers](https://agentwranglers.se/playbook/website/errors-and-outages/browser-error-reports.md) · 955 tokens · updated 2026-10-22
  Send every uncaught script error and rejected promise from the browser to your own endpoint, and alert when they rise.

## Optional

- WEB-226 [Warn before retiring an address](https://agentwranglers.se/playbook/website/errors-and-outages/deprecation-and-sunset.md) · 684 tokens · updated 2026-10-22
  Before you retire an address or API, announce it with `Deprecation` and `Sunset` headers.

- Previous: [Privacy](https://agentwranglers.se/playbook/website/privacy.md)
- Next: [Offline and installed apps](https://agentwranglers.se/playbook/website/offline-and-installed-apps.md)
- [All chapters](https://agentwranglers.se/playbook/website.md)