{"slug":"cors-header-checker-8ca6d41e","name":"CORS Header Checker","summary":"Sends a real request to any URL you provide, attaches an Origin header, and reads back all six standard cross-origin permission headers the server returns. Tells you whether cross-origin requests are enabled at all, whether your specific origin is permitted, and shows every permission value exactly as the server sent it. Useful for finding why a browser is blocking a request, confirming a new deployment is configured correctly, or auditing whether a public API allows credentialed calls.","status":"live","indexable":true,"listed_since":"2026-10-25T17:50:14.154419Z","sources":[{"source":"x402_bazaar","external_id":"https://cors-header-checker.underscoredone.com/check","owner_address":"0xe9740820225b3918b4ddd1292c7ca4ca0e2c2f08","seen_at":"2026-10-26T05:59:07.343728Z","removed_at":null}],"endpoints":[{"url":"https://cors-header-checker.underscoredone.com/check","host":"cors-header-checker.underscoredone.com","protocol":"x402","state":"live","last_probe_at":"2026-10-25T18:19:29.233563Z","last_ok_at":"2026-10-25T18:19:29.233563Z","tools_count":null,"tools_changed_at":null,"uptime_24h":1.0,"uptime_30d":1.0}],"also_listed_as":[{"slug":"cors-header-checker-underscoredone-com-b4c1ab2e","name":"cors-header-checker.underscoredone.com"}],"payment_options":[],"usage":{"source":"x402_bazaar","unique_payers_30d":6,"paid_calls_30d":7,"last_paid_at":"2026-10-21T21:08:24.514Z","reported_at":"2026-10-26T05:59:07.343728Z"},"notice":"Not affiliated with addrbook — claim or request removal."}