Create and manage a remote online notarization (RON) session end-to-end via the BlueNotary integration API (v2), including document upload and signer setup.

Steps

1. Authenticate all requests with an API key in the Authorization header (Bearer token format); note that as of October 10, 2025, a missing/invalid key returns 401 Unauthorized (previously returned a misleading 500 error).
2. Use the v2 base URL https://app.bluenotary.us/api/integrationsv2/ for all API requests, e.g. POST https://app.bluenotary.us/api/integrationsv2/sessions.
3. Create a session by POSTing notarization_id (your tracking ID, max 255 chars), signing_type, notarization_timing_type, and an all_signers array with first_name, last_name, and email for each signer.
4. Optionally attach documents at session-creation time as base64-encoded strings, or add them afterward via the separate Add Document endpoint.
5. Handle the response: a successful call returns 200/201 with bn_session_id and per-signer signing_urls (both a relative bn_signing_url and a full_signing_url); a validation failure returns 403 with an explanatory response_message.