[Good First Issue] Improve test coverage to 80%+ with API route tests

[pixelstrade-dev]

Description

The current test suite covers the scoring engine but API routes need more comprehensive testing. Target: 80%+ code coverage.

What to do

1. Add tests for /api/chat route (valid request, invalid body, rate limiting, session management)
2. 2. Add tests for /api/debate route (create debate, advance turns, conclude)
3. 3. Add tests for /api/debate/[id] route (GET detail, POST advance)
4. 4. Add tests for /api/sessions and /api/scores routes
5. 5. Configure coverage reporting with Istanbul/c8

Skills needed

• TypeScript
• • Vitest or Jest
• • • API testing

References

• Existing tests: apps/web/__tests__/
• • API routes: apps/web/app/api/
• • • Test config: apps/web/vitest.config.ts

[m13v]

for getting API route tests to 80%, start by listing all routes and testing the error paths first. in our experience, the happy paths usually work fine, it is the 400/401/404/500 responses that are undertested and where real bugs hide. use a test helper that automatically validates response schemas (zod or joi) so you catch type drift between server and client early. also test that unauthenticated requests to protected routes return 401 consistently, not a mix of 401 and 403 which is a common inconsistency.

[m13v]

if you want to auto-discover which API routes need test coverage, we open sourced a tool that crawls your app and maps out all the endpoints and user flows, then generates Playwright test files: https://github.com/assrt-ai/assrt-sdk - could help prioritize which routes to test first.