GetResponse API v3
The complete GetResponse API v3 — a JSON REST API of 220 operations across 141 paths and 42 product areas, described by a provider-published OpenAPI 3.0.0. Authentication is an X-Auth-Token header carrying an API key prefixed with "api-key ", or OAuth 2.0 with a single "all" scope. Every response carries X-RateLimit-* headers; errors return a custom ErrorResponse envelope discriminated by a numeric code rather than by HTTP status.