nx_source_health_probe.nx

nx_source_health_probe.nx -- the BOUNDED PROBE half of /compare/mediaingest R1 (source health pre-flight). The reusable decision, persistence, skip and no-reprobe logic all live in nx_source_health.nx (sh_preflight), gate-proven by nx_source_health_gate 12/12 with planted numbers and no network. THIS file is the thin driver that produces those numbers from a REAL remote host: it composes the shipped Chrome-hello fetch (nx_https_fetch_follow_chrome -- the one that gets past anti-bot RSTs and follows redirects, giving both the body and the HTTP status) and the shipped bot-wall classifier (nx_antibot abt_classify), times the round-trip, and hands the outcome to sh_preflight, which classifies UP / SLOW / DEAD(null-routed) / WALLED and PERSISTS it. The flagship case -- a null-routed CDN (Coomer, April 2026) -- is a connect that never completes: the fetch returns no bytes and status 0, so connect_ok=0 and the verdict is DEAD, skipped with its reason, before any item is queued against it. USAGE nx_source_health_probe <url> probe the host, classify, persist, print the verdict row nx_source_health_probe check <host> read the persisted verdict (the cheap row the queue reads); prints skip=0|1 A url begins with 'h' (http...) so it can never collide with the literal verb `check`. EXIT CODES (each is the verdict, so a caller can branch on it without parsing): 0 UP 1 SLOW 2 DEAD 3 WALLED 4 UNKNOWN(could not load trust store / usage) license_tier: ORIGINAL No hw writes (Rule 26).