# Fix llms.txt returning 404 while llms-full.txt works

> Diagnose why your documentation site's llms.txt file returns a 404 error while llms-full.txt still loads, usually caused by the Don't index project setting.

Mintlify automatically hosts an [`llms.txt`](/guides/agent-ready-content-ai-llmstxt) file at the root of every documentation site. If `https://yourdocs.com/llms.txt` returns `404` while `https://yourdocs.com/llms-full.txt` loads normally, the most likely cause is the **Don't index project** setting.

## Check the Don't index project setting

When you enable **Don't index project** on the [General](https://app.mintlify.com/settings/project/general) page of your dashboard, Mintlify returns `404` for `llms.txt` and `/.well-known/llms.txt`. The setting does not gate `llms-full.txt`, which stays available. This mismatch makes the missing `llms.txt` look like a deployment bug when it is a configured behavior.

The Markdown export of each page (the `.md` URL) also keeps its pointer to `/llms.txt` after you enable **Don't index project**, even though that URL returns `404`.

To restore `llms.txt`:

1. Open the [General](https://app.mintlify.com/settings/project/general) page of your dashboard.
2. Turn off **Don't index project**.
3. Wait for the redeployment to complete. Enabling or disabling indexing redeploys your site, and the change takes effect after the redeployment finishes.

See [Disable indexing for the entire project](/guides/agent-ready-content-optimize-seo#disable-indexing-for-the-entire-project) for everything else this setting controls.

## Other causes

If **Don't index project** is off and `llms.txt` still returns `404`:

- **Authentication**: On fully authenticated sites, both `llms.txt` and `llms-full.txt` require authentication. Unauthenticated requests fail for both files, not just `llms.txt`. See [llms.txt](/guides/agent-ready-content-ai-llmstxt) for how authentication affects each file.
- **Reverse proxy routing**: If you serve your documentation through a reverse proxy with a path allowlist, confirm the proxy forwards `/llms.txt` and `/.well-known/llms.txt`. See [Reverse proxy](/guides/manage-your-site-deploy-reverse-proxy#routing-configuration).

## Related topics

- [llms.txt](/guides/agent-ready-content-ai-llmstxt)
- [SEO](/docs/optimize/seo.md)
- [Mintlify CLI command reference](/guides/get-started-cli-commands)

## Related pages

- [Admin](./admin-index.md)
- [Agent](./agent-2-index.md)
- [Agent](./agent-index.md)
- [Agent-ready content](./agent-ready-content-index.md)
- [AI](./ai-index.md)
- [Analytics](./analytics-index.md)
- [API docs](./api-docs-index.md)
- [API reference](./api-reference-index.md)
- [Assistant](./assistant-2-index.md)
- [Assistant](./assistant-index.md)

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