Interactive API explorers in Rest API - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this API explorer request?

You use an interactive API explorer to send a GET request to https://api.example.com/users/123. The response JSON is:

{"id":123,"name":"Alice","active":true}

What will the explorer show as the value of active?

A 1

B "true"

C True

D true

💡 Hint

Remember JSON boolean values are lowercase true or false.

The JSON boolean true is shown as true in the API explorer, not as a string or Python boolean.

🧠 Conceptual

intermediate

Which feature is typical of an interactive API explorer?

Choose the feature that best describes what an interactive API explorer does.

A Automatically generates API documentation from code comments.

B Compiles API code into executable binaries.

C Allows users to send API requests and see live responses in a user interface.

D Encrypts API requests for secure transmission.

💡 Hint

Think about what you do when you want to test an API endpoint interactively.

Interactive API explorers let you send requests and view responses live in a friendly interface.

🔧 Debug

advanced

Why does this API explorer request fail with a 401 error?

You use an interactive API explorer to send a POST request to /api/data with a JSON body. The server responds with 401 Unauthorized. You included the header Authorization: Bearer but left the token empty.

What is the most likely cause?

A The Authorization header is missing a valid token.

B The API explorer does not support POST requests.

C The JSON body is malformed and causes a server error.

D The API endpoint requires a GET request, not POST.

💡 Hint

401 means unauthorized. Check your authentication details.

An empty token in the Authorization header means the server rejects the request as unauthorized.

📝 Syntax

advanced

Which JSON body is valid for this API explorer POST request?

You want to send this JSON body in an API explorer POST request:

{"name": "Bob", "age": 30, "active": true}

Which option is a valid JSON string for the body?

A {name: "Bob", age: 30, active: true}

B {"name": "Bob", "age": 30, "active": true}

C {"name": "Bob", "age": "30", "active": "true"}

D {"name": "Bob", "age": 30, "active": True}

💡 Hint

JSON keys and string values must be in double quotes. Boolean values are lowercase.

Option B is valid JSON. Option B misses quotes on keys. Option B uses strings for numbers and booleans. Option B uses Python boolean True which is invalid in JSON.

🚀 Application

expert

How does an interactive API explorer handle pagination?

You use an interactive API explorer to fetch a list of items from an API that supports pagination with page and limit query parameters.

Which approach best describes how the explorer helps you get all items?

A It requires you to manually change the <code>page</code> parameter and resend requests.

B It automatically sends multiple requests incrementing <code>page</code> until no more items are returned.

C It ignores pagination and only shows the first page of results.

D It merges all pages into one response by modifying the API server.

💡 Hint

Think about what an explorer can do without custom automation.

Most interactive API explorers let you change query parameters manually and resend requests to see different pages.