Platform: ios · Severity: error (fails the check)
What and why
iOS (through Apple's CDN) fetches https://<rpId>/.well-known/apple-app-site-association. It must be HTTPS, status 200, JSON, without redirects, below 128 KB, ideally Content-Type: application/json.
Checked by
passkiCheck, passkiVerify, PasskeyDoctor. Runtime symptom: error 1004 "not associated".
Fix
Serve https://<rpId>/.well-known/apple-app-site-association over HTTPS with status 200, JSON body and no redirects.
./gradlew passkiSetup # writes build/passki/well-known/apple-app-site-association