Chord Audiences API
Read API for activated audiences. Once the Dynamic Audiences API destination is enabled on an account, a sync mirrors a custom audience into the API and a server-side GET on /audiences returns that user's audience memberships with their attached attributes. Keyed by the CDP Blended User ID passed in the Chord-User-Id header and authenticated with a bearer token issued by Chord. Intended for on-site personalization; Chord's docs state it must always be called server-side.