Debugging Network Issues

Evidence-driven investigation methodology for incidents where the obvious cause is probably wrong. Built from a real 5-hour production case (see references/case-sse-rst-130s.md) where assumption-stacking wasted hours that a 10-minute layered experiment would have resolved.

Apply this skill when the user reports a network/streaming/protocol symptom and the investigator feels tempted to diagnose from one log line or one circumstantial data point. The skill's job is to slow that reflex down.

Triage first — is this a known domain?

Before applying the general methodology below, check whether the symptom points at a stack that already has a dedicated skill in this repo. Those carry the domain-specific symptom→cause→fix tables this skill deliberately stays general about — start there, and come back here for methodology if the root cause turns out to be elsewhere.

If none match — or you tried a domain skill and the evidence points elsewhere — continue below. The methodology generalizes to any multi-layer system.