For X, LinkedIn and Threads, register these exact callbacks after replacing the example API origin:
https://posted-api.example.com/social/bluesky/client-metadata.json. Supply an EC P-256 private signing JWK with a key ID. Posted serves client metadata and public keys at /social/bluesky/client-metadata.json and /social/bluesky/jwks.json; it never serves the private JWK.
Consult the provider’s current registration and approval instructions: X OAuth, LinkedIn member sharing, Threads and Bluesky OAuth.
After configuration, an administrator connects a test account and confirms its granted permissions. Verify one authorized text, image and video delivery for each provider you intend to use, and inspect provider-side results. Treat provider approval and a real publishing smoke test as separate from Posted’s local contract tests.