API / Swagger Interview questions

What is Swagger UI?

Swagger UI is a tool that takes any valid OpenAPI document and renders it as an interactive documentation website, without requiring the API team to write a separate documentation page by hand or keep two sources of truth synchronized.

Beyond just displaying endpoints and their parameters, Swagger UI includes a "Try it out" feature that lets a developer fill in parameter values directly in the browser, send a real request to a live API, and see the actual response — turning static reference documentation into something closer to an interactive API console.

Because it's driven entirely by the underlying OpenAPI document, any change to the spec — a new endpoint, an updated parameter description, a changed response schema — is reflected in the rendered UI automatically the next time it loads the document, with no manual documentation update step required in between.

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What does Swagger UI's 'Try it out' feature let a developer do? Compile the API's source code

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Delete an endpoint permanently

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Send a real request to a live API directly from the browser

✓ Correct! Well done.

What keeps Swagger UI's rendered documentation up to date? A developer must manually retype the docs every day

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It never updates once generated

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It's driven directly by the underlying OpenAPI document

✓ Correct! Well done.

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