API Drawer

Guide

Turn OpenAPI, cURL, and sample responses into AI-ready API docs

AI coding tools write better code when they know exactly what an API takes and returns. This guide shows how to fill in an API's request parameters and response fields from what you already have, then export a clean Markdown brief.

What you can paste

  • OpenAPI (Swagger) definition in JSON: fills request parameters and response fields from the first endpoint in the file.
  • cURL command: fills request parameters from the query string and JSON body.
  • Sample JSON response: fills response fields, with types and examples taken from the values.
  • TypeScript interface or type: fills fields from its properties.
  • Excel or CSV table: a spec table (name, type, description) or rows of real data.

Step by step

  1. 1Sign in and open My APIs, then click Add an API. Fill in the name, method, base URL, and path.
  2. 2In the Request parameters or Response fields table, click Smart fill.
  3. 3Paste your OpenAPI JSON, cURL command, sample response, TypeScript type, or table. Auto-detect picks the format, or you can choose it yourself.
  4. 4Check the preview and click Add. Existing fields stay as they are, and duplicate names are skipped.
  5. 5Save the API, then paste a real response on its details page so your docs include a sample.
  6. 6Go to Export, pick the APIs you need, and copy the Markdown brief into ChatGPT, Claude, or Cursor.

Coming from Postman or another API client?

Most API clients, including Postman, can copy a request as a cURL command. Copy the request as cURL, then paste it into Smart fill to fill in its request parameters. For response fields, paste a real response body from your client.

Example: a cURL command

curl "https://api.example.com/v1/forecast/hourly?zip=10001&date=2026-09-29" \
  -H "X-API-Key: YOUR_API_KEY"

Smart fill finds the zip and date query parameters and adds them to the Request parameters table.

Tips

  • Mask names, phone numbers, emails, and keys before you paste a real response.
  • Add a one-line description to each field. It's the part your AI uses most.
  • Long arrays are trimmed to 3 items in exports, so your AI's context window doesn't fill up.

Keep the APIs you use in one drawer

Save field notes and sample responses, combine APIs into product ideas, and hand your AI a clean brief.

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Last reviewed: October 2026. Product details are based on each company's public website and documentation.

Product names are trademarks of their respective owners. API Drawer is not affiliated with or endorsed by any of the companies listed here.