Makes a live HTTP request to a URL and reports the status code, latency, and full redirect chain. Use this to check whether a site is up, slow, or stuck in a redirect loop.

Opens a live TLS connection to a hostname and reports certificate issuer, validity window, days until expiry, and subject alternative names. Use this to diagnose SSL warnings or expiry issues.

Looks up live DNS records (A, AAAA, CNAME, MX, TXT, NS) for a domain. Use this to diagnose propagation delays, missing records, or misconfigured mail/DNS setups.

Fetches a URL and checks its response headers against a standard security checklist (CSP, HSTS, X-Content-Type-Options, X-Frame-Options, Referrer-Policy, Permissions-Policy), noting the risk for each missing header.

Searches a curated knowledge base of hosting/web-server troubleshooting notes (502/504 errors, mixed content, DNS propagation, SSL chain issues, CORS, rate limiting, and more) using hybrid vector + keyword search. Returns the most relevant notes for a described symptom.

The main entry point: given a URL and a description of the symptom, runs every live check (HTTP status, SSL, DNS, security headers) in parallel alongside a knowledge-base search, and returns one structured report. Use this first for an open-ended 'why is my site doing X' question; use the individual check_* / search_troubleshooting_kb tools when you already know exactly what to check.