REST and GraphQL debugging

Diagnose the smallest reproducible failing request. Confirm target, expected behavior, credentials source, and whether state-changing requests are authorized. Use an available HTTP tool or shell with curl. Python examples require the optional requests package; check before use and prefer curl if unavailable. Do not install dependencies into the user's environment implicitly.

1. Capture the failing request, status, headers, request ID, and sanitized body.
2. Work outward-in: connectivity → timeouts → TLS → authentication → request format → response parsing → business semantics. Change one variable at a time.
3. For GraphQL, inspect errors even on HTTP 200. A transport success does not establish a successful operation.
4. Reproduce a fix and verify failure cases, pagination, or idempotency where relevant. Do not retry state-changing requests without establishing safety.
5. Report observed vs expected behavior, sanitized repro, root cause confidence, proposed fix, and tests run/not run. Never expose credentials in logs or chat.

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