# Page Not Found

The URL `build-apps/guides/authentication` does not exist.

You might be looking for one of these pages:
- [Authentication](https://docs.stacks.co/get-started/build-a-frontend/authentication.md)
- [Sending Transactions](https://docs.stacks.co/get-started/build-a-frontend/sending-transactions.md)
- [Post-Conditions](https://docs.stacks.co/get-started/build-a-frontend/post-conditions.md)
- [Integrations](https://docs.stacks.co/clarinet/integrations.md)
- [Build Transactions](https://docs.stacks.co/stacks.js/build-transactions.md)

## How to find the correct page

1. **Browse the full index**: [/sitemap.md](https://docs.stacks.co/sitemap.md) - Complete documentation index
2. **View the full content**: [/llms-full.txt](https://docs.stacks.co/llms-full.txt) - Full content export

## Tips for requesting documentation

- For markdown responses, append `.md` to URLs (e.g., `/get-started/build-a-frontend/authentication.md`)
- Use `Accept: text/markdown` header for content negotiation