# fast_rs

> Fast Api but in rust

- Documentation: https://fast-rs.thally.app
- GitHub: https://github.com/mahmudsudo/fast-rs
- Full docs for LLMs: https://fast-rs.thally.app/llms-full.txt
- Agent discovery (ai.txt): https://fast-rs.thally.app/ai.txt
- Structured docs index (JSON): https://fast-rs.thally.app/api/docs-index
- OpenAPI spec: https://fast-rs.thally.app/openapi.yaml

## For AI agents

Every page supports content negotiation on its human URL:
- JSON API: append `?format=json` or send `Accept: application/json`
- JSON-LD: append `?format=ldjson` or send `Accept: application/ld+json`
- Markdown: append `?format=md` or send `Accept: text/markdown`
- Per-page API: https://fast-rs.thally.app/api/docs/{page-id}
- Search API: https://fast-rs.thally.app/api/search?q={query}
- Capability manifest (skill): https://fast-rs.thally.app/skill.md
- Agent guidance (editing these docs): https://fast-rs.thally.app/AGENTS.md
- MCP server (attach docs as native tools): https://fast-rs.thally.app/api/mcp
- Agent readiness: https://fast-rs.thally.app/api/agent-readiness
- Changelog feed (JSON Feed): https://fast-rs.thally.app/changelog/feed.json
- Changelog feed (RSS): https://fast-rs.thally.app/changelog/rss.xml

### Recommended workflow

1. Use this index, the search API, or `search_sections` / `search_docs` before choosing a page.
2. Read the smallest set of relevant pages and follow their prerequisite links.
3. Treat the published docs as the source of truth. Label inferences and say when evidence is missing.
4. Cite the canonical human page URLs, not only API endpoints.
5. Use `/AGENTS.md` before editing a repository. The public MCP server is read-only.

## Documentation

### Overview

- [Introduction](https://fast-rs.thally.app/): fastrs is a thin ergonomics layer on Axum 0.7 that adds compile-time OpenAPI generation, automatic request validation, and minimal boilerplate for Rust web APIs.

### Getting Started

- [Quickstart](https://fast-rs.thally.app/quickstart): Install fastrs, write a validated route with auto-generated OpenAPI docs, and run the server.

### API Reference

- [App builder](https://fast-rs.thally.app/api/app-builder): Build and configure a fastrs application with routes, middleware, shared state, and auto-generated API docs.
- [Routing and route macros](https://fast-rs.thally.app/api/routing)
- [OpenAPI Schema Generation](https://fast-rs.thally.app/api/openapi)
- [Extractors](https://fast-rs.thally.app/api/extractors): Parse and validate request data with built-in extractors that integrate with OpenAPI documentation.
- [Authentication](https://fast-rs.thally.app/api/authentication): Implement bearer token authentication with the AuthVerifier trait and Bearer extractor.
- [Error handling](https://fast-rs.thally.app/api/error-handling): Return structured JSON errors with ApiError, map application errors with IntoApiError, and generate OpenAPI error documentation automatically.
- [Response types](https://fast-rs.thally.app/api/responses): Return JSON bodies, 201 Created, and 204 No Content responses with automatic OpenAPI documentation.
- [Middleware](https://fast-rs.thally.app/api/middleware): Add CORS, tracing, rate limiting, request IDs, and custom Tower layers to a fastrs application.
- [HTMX Integration](https://fast-rs.thally.app/api/htmx): Use HTMX extractors and responders in fastrs routes with automatic OpenAPI header documentation.

### Guides

- [State and database integration](https://fast-rs.thally.app/guides/state-and-database): Share application state across handlers and integrate a database pool with proper error mapping.
- [Health checks and API versioning](https://fast-rs.thally.app/guides/health-checks-and-versioning): Add health check endpoints and organize versioned APIs using route nesting.
- [Deployment](https://fast-rs.thally.app/guides/deployment): Configure host and port, understand graceful shutdown behavior, and build a Docker image for a fastrs application.
- [Validation and docs](https://fast-rs.thally.app/guides/validation-docs): Enforce rules on incoming JSON, read the error responses, and see the same rules in the generated OpenAPI spec.

### Reference

- [Changelog](https://fast-rs.thally.app/changelog): All notable changes to fastrs, organized by release.