OpenAPI Required Fields Check

The four required pieces

The info.version value is the version of your own API, not of the OpenAPI specification. People often leave it out because the spec version is already at the top.

A worked example with everything missing

servers:
  - url: https://api.example.com

This tiny document has none of the required pieces. The report lists three errors:

When the whole info object is absent, the tool reports that one error and does not also list the title and version separately. Add info with both fields and the next run will report them if either is still missing.

Starter skeleton

openapi: 3.0.3
info:
  title: Orders API
  version: 1.0.0
paths:
  /orders:
    get:
      summary: List orders

This skeleton clears every required-field check. Replace the names with your own and build outward from there. Responses, schemas and security are not part of this check.

When to run this check

Run it when you start a new spec from scratch, after generating one from code, and before sending it to anyone who will import it into another tool. Many importers stop at the first missing required field with a short message, so catching all of them in one pass saves several round trips. It is also a handy reminder for newcomers, who often forget info.version or leave paths out while sketching an API.

After the required fields pass, the next useful additions are a short description under info, a servers entry and an operationId on each operation. None of these are checked here, but they make the spec easier to read and to turn into client code.