# API Explorer

## Objective

Let developers try real API requests from inside the app.

An in-app request builder that runs calls against your API and shows the exact request and response.

## Before You Begin

This feature is being added to an application that already exists and already
works. Do not scaffold a new project, and do not assume a blank slate.

Inspect the codebase first and establish:

- The existing application structure and where code of this kind already lives.
- The framework and version in use.
- The existing design system — colours, spacing, typography, and component conventions.
- Existing UI components you can reuse instead of writing new ones.
- The existing database structure, if this feature needs to persist anything.
- The existing authentication and authorization system, if this feature is user-scoped.
- Dependencies already installed, so you don't add a library that duplicates one.
- The existing test setup and conventions.

Only start writing code once you understand the above. If the application
already implements part of this feature, extend it rather than replacing it.

## Implementation Instructions

1. Generate the request form from the API's own schema so parameters, types, and required fields cannot drift from the real endpoints.
2. Execute calls through a server-side proxy that attaches credentials, so a key is never placed in browser-visible code or the network tab.
3. Restrict the proxy to your own documented API endpoints only. An explorer that will call an arbitrary URL is an SSRF hole with a nice UI.
4. Run requests with the current user's real permissions and show endpoints they cannot call as denied rather than hiding them — a silent omission reads as a missing feature.
5. Mark unsafe methods clearly and confirm before sending. A POST from a documentation page still creates real data.
6. Do NOT store request or response bodies in history without redacting authorization headers, tokens, and any field the API marks sensitive.

## UI and UX Requirements

Match the application's existing design system exactly. Reuse its components,
spacing, and typography. This feature should look like it was always there.

## Responsive Requirements

Works on mobile, tablet, and desktop. Touch targets are large enough to hit on a
phone, and nothing overflows horizontally at 320px.

## Accessibility Requirements

- Fully keyboard navigable.
- Correct semantic elements and ARIA roles.
- Visible focus states.
- Meets WCAG AA contrast.
- Dynamic changes are announced to screen readers.
- Respects prefers-reduced-motion.

## Edge Cases

- Copyable curl and code samples must contain a placeholder, never the live credential the proxy used.
- Very large responses will freeze the browser if rendered whole. Truncate with a way to download the full body.
- Requests must time out and be cancellable, or a slow endpoint hangs the panel indefinitely.
- Explorer traffic counts against rate limits. Label it distinctly so a developer can tell exploration from production usage.
- The explorer must follow the API version the account is pinned to, and say which version it is calling.
- Where the API has a sandbox or test mode, default the explorer to it and make switching to live an explicit, obvious act.

## Testing

Exercise the feature end to end in the running application. Cover every edge case
above, then run the existing test suite and confirm nothing regressed.

## Acceptance Criteria

- [ ] The request form is generated from the API schema, not hand-maintained.
- [ ] Credentials are attached server-side and never exposed to the browser.
- [ ] Only documented first-party endpoints are reachable through the proxy.
- [ ] Permission-denied endpoints are shown as denied rather than omitted.
- [ ] Stored history has authorization headers and sensitive fields redacted.
- [ ] Generated code samples use credential placeholders.
- [ ] The feature matches the existing design system.
- [ ] No existing functionality is broken.

## Adaptation Rules

- Match the existing design system. Do not introduce a new colour palette,
  spacing scale, or component library.
- Reuse existing components and utilities wherever they fit.
- Follow the naming, file layout, and code style already present.
- Do not upgrade, replace, or remove existing dependencies to make this
  feature fit. Adapt the feature to the app, not the app to the feature.
- Do not break existing functionality. If a change is genuinely required in
  existing code, make the smallest one that works and say so.
- If something in these instructions conflicts with how the application is
  built, follow the application and explain the deviation.

## Final Verification

Before you report the work as done:

1. Re-read the acceptance criteria above and check each one against what you
   actually built.
2. Run the application and exercise the feature end to end.
3. Run the existing test suite and confirm you have broken nothing.
4. Check the feature on mobile, tablet, and desktop widths.
5. Check keyboard navigation and focus handling.
6. Summarize what changed: files added, files modified, and anything you
   deliberately did differently because of how this application is built.

If any acceptance criterion is unmet, fix it before reporting completion.