Technical
API Documentation Generator
Good API documentation is what separates tools developers love from tools they avoid. Describe your endpoint and get complete, formatted docs in seconds.
AI-generated output
Fill in the endpoint details above and click Generate to get your API documentation.
How it works
Enter the endpoint path, HTTP method, and a plain English description of what it does. Then describe the parameters it accepts and the shape of the response.
Select the authentication type your API uses and the documentation format you need. The AI generates docs that are consistent with the conventions of your chosen format.
You get a complete endpoint documentation block with a description, parameter table, request example, response schema, and common error codes — ready to drop into your documentation site or OpenAPI spec.
Practical example
For example, describe a POST /users/invite endpoint that accepts an email address and role, and returns the new user object with an invitation token, and you get a full documentation block with cURL request example, JSON request body, JSON response schema, and error codes for invalid email, duplicate user, and insufficient permissions.
The documentation follows REST API documentation conventions — clear parameter descriptions with types, required/optional flags, and example values — matching the quality of documentation from well-regarded developer platforms.
Frequently asked questions
What format should API documentation be in?
The two dominant formats are OpenAPI/Swagger (a machine-readable YAML or JSON spec that can auto-generate interactive docs) and Markdown prose documentation (more human-readable, easier to write, harder to keep in sync with the code). The best developer platforms use both: an OpenAPI spec for reference accuracy and prose documentation for guides and tutorials. This tool generates Markdown-formatted documentation that you can convert to OpenAPI with additional tooling.
What are the most important elements of a good API endpoint doc?
In order of importance: (1) a one-sentence description of what the endpoint does, (2) a complete request example (cURL or code snippet) that actually works, (3) a complete response example, (4) a parameter table with types, required/optional, and validation constraints, (5) error codes and their meaning. Missing any of these forces the developer to guess or test — which erodes trust in the API and increases support burden.
How do I keep API documentation up to date?
The hardest part of API documentation is maintenance. The most effective approach is to generate documentation from code annotations (tools like Swagger UI, Stoplight, or Redocly can auto-generate docs from OpenAPI specs embedded in your code). For manually maintained docs, add documentation updates to your definition of done for any API change — so it cannot be shipped without updated docs. Stale documentation is often worse than no documentation.
Should I document internal APIs the same way as public ones?
Internal APIs between your own services do not need the same polish as public-facing developer APIs, but they benefit from the same structure. At minimum, document: what the endpoint does, what it returns, and what errors it can throw — even if only as inline code comments or a lightweight Markdown file in the service repository. Undocumented internal APIs create onboarding friction and become impossible to reason about at scale.
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