How I Built My First API Documentation Projects Using Postman and Swagger
Prasanna Rengaraju👋 Hello everyone, I'm Prasanna, an aspiring API writer transitioning from a technical support background. In this post, I’ll walk you through how I built hands-on API documentation projects using real-world public APIs and tools like Postman, Swagger, and GitHub.
Why API Documentation?
Coming from a computer science background and working in a client-facing role, I always enjoyed explaining technical processes clearly. I realized that API documentation blends technical understanding with clear writing—and that’s where I found my niche.
Tools I Used
🔧 Postman – to test and document API endpoints
🛠️ Swagger Editor (OpenAPI 3.0) – to write clean, structured YAML docs
💻 GitHub – to publish and organize my documentation
📝 Markdown – to write human-readable documentation
My Projects
🌤 OpenWeatherMap API (Postman)
I documented:
Current Weather by City
5-Day Forecast
Forward and Reverse Geocoding 🔗 View Documentation
🛒 FakeStore API (Postman)
I covered:
Product Catalog
Carts and Users
Authentication 🔗 View Documentation
⚙️ OpenWeatherMap (Swagger/OpenAPI)
I converted Postman requests to Swagger YAML:
Structured the paths, queries, and responses
Wrote detailed parameter descriptions 🔗 GitHub Repo
What I Learned
Designing API docs for readability and reuse
Using variables, examples, and folders in Postman
Writing nested fields in Swagger
Documenting errors like 401, 400, and sample payloads
Publishing everything on GitHub with Markdown
Building developer-friendly API’s
Swagger/OpenAPI 3.0 is not easy at first, but now I enjoy it
What’s Next?
I'm continuing to improve by writing blogs, exploring open-source projects, and applying for entry-level API writer roles in product-based companies. My goal is to make developer documentation more accessible, readable, and useful. I’ll continue to write more public API’s, contributing to open-source projects, and applying for API writer roles targeting Chennai and Bangalore.
Connect With Me
Thanks for reading! If you're transitioning into API writing too, feel free to reach out!
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