API Documentation Generator
Generate comprehensive, developer-friendly API documentation with endpoint specs, request/response examples, authentication guides, and error references.
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Expect clean code blocks with comments, plus a short explanation of what changed.
How to Use API Documentation Generator
- Paste your API details — endpoint paths, methods, parameters, request/response bodies, or even raw code from your router/controller files.
- Select the API type (REST, GraphQL, gRPC, or WebSocket) for protocol-specific documentation patterns.
- Choose your authentication method so the docs include proper auth setup guides and code examples.
- Pick an output style — OpenAPI for machine-readable specs, Markdown for GitHub, or Developer Portal for a Stripe-style experience.
Use Cases
Generate OpenAPI 3.0 specs from existing route definitions for Swagger UI
Create developer portal documentation for a public API launch
Document internal microservice APIs for team onboarding
Produce GraphQL schema documentation with query examples
Build WebSocket API docs with connection lifecycle and event catalogs
Tips for Best Results
- Include real field names and data types in your input — the generator produces much better docs when it knows your actual schema.
- Paste your route definitions or controller code directly; the AI can extract endpoints, parameters, and response shapes automatically.
- For OpenAPI output, the generated spec can be imported directly into Swagger UI, Redoc, or Stoplight for interactive documentation.
- Always review generated error responses — add any domain-specific error codes your API returns.
Frequently Asked Questions
Can I paste my actual code instead of describing the API?
Yes. You can paste route definitions (Express, FastAPI, Spring Boot, etc.), controller files, or even database models. The generator will extract endpoint information, parameters, and response structures from your code.
Is the generated OpenAPI spec valid?
The generated OpenAPI 3.0 spec follows the official specification structure. You can validate it with the Swagger Editor or any OpenAPI linter. Minor adjustments may be needed for complex schemas.
How do I document WebSocket events?
Select 'WebSocket API' as the type. The generator will produce documentation covering connection setup, authentication handshake, event types (client-to-server and server-to-client), message formats, heartbeat/ping-pong, and reconnection strategies.
Does it support multiple authentication methods?
Select the primary authentication method from the dropdown. If your API supports multiple methods, mention the additional ones in your API description and the generator will document all of them.
Can I generate docs for a GraphQL API?
Yes. Select 'GraphQL API' as the type and provide your schema, queries, mutations, and subscriptions. The output will include type definitions, query examples, variable usage, and error handling patterns specific to GraphQL.
How detailed are the error response examples?
Each endpoint includes common HTTP error responses (400, 401, 403, 404, 422, 429, 500) with realistic JSON error bodies, error codes, and human-readable messages. A consolidated error reference table is also generated.
Part of these workflows
This tool is used in step-by-step guides that help you get more done
We don't store your text. Processing happens in real-time and your input is discarded immediately after generating the result.
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Free users: 5 uses per day | Pro users: Unlimited
This tool is a step in the following agent workflows:
See how this tool stacks up side-by-side:
✍️ Prompt Library
Ready-to-use prompts — click "Use This" to auto-fill the tool
Write a Python function that [describe what it does]. Include type hints and a docstring.
Explain this code and suggest improvements: [paste code]
Generate unit tests for the following function: [paste function]
Write a SQL query to [describe what you need] from a table with columns [list columns].
Create a README.md for a [project type] project with installation, usage, and contributing sections.
