Postman is a handy tool for exploring and debugging APIs.

What to test

• URL + method
• Query parameters
• Headers (Content-Type, Authorization)
• JSON body
• Status codes
• Response schema

Common Postman setup

POST JSON

• Method: POST
• Body: raw → JSON

Example payload:

{ "title": "Buy milk" }

{ "title": "Buy milk" }

Add headers

• Content-Type: application/jsonContent-Type: application/json

Auth testing

When you add token auth later, you’ll often set:

• Authorization: Bearer <token>Authorization: Bearer <token>

Postman can store variables and environments for tokens.

Debugging tips

• If Flask returns 415 Unsupported Media Type, your Content-Type might be wrong.
• If you get 400, inspect validation errors.
• If you get 401/403, inspect Authorization header.

Bonus: keep docs in sync

If you maintain an API, consider documenting endpoints with:

• OpenAPI (Swagger)

That’s a more advanced step, but worth it for real projects.