Unencoded query params Debugging Lab

Unencoded query paramsHTTP/APIMediumPreparing workspaceAutosaved

00:00

Incident Dossier

Unencoded query params

Search requests with spaces, ampersands, slashes, or `=` in the input string produce malformed query strings. The upstream API returns 400 for what looks like a well-formed search. The bug is not in the input — it is in how the value is joined into the URL.

Initial failing signalSearch URL with spaces and ampersand is not parseableExpected URL with encoded spaces and ampersands · received URL with raw spaces and ampersands breaks the query

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Run npm test.
Inspect the failing URL string in the assertion.
Trace how buildUrl joins parameters.
Apply per-component URL encoding before joining.

Focus Mode

Start

src/url.js

Likely area

src/url.js

Progressive hints

Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicHTTP/API

DifficultyMedium

Est. time14 min

Workspacecreating

Explorer

Preparing workspace files…

Evidence Map

Failing signal loaded from challenge API
Workspace files loaded from workspace API
Results rendered only after API run/submit

Autosaved

workspace

Outputread-onlyready$ workspace boot

Workspace booting...