Which Appian object is commonly used to expose Appian services to external callers?

• A. Connected System Object
• B. Initiate Call Smart Service
• C. Integration Object
• D. Web API

Answer: (D)

Web API endpoints are how Appian exposes services to external callers. By creating a Web API object, you publish RESTful endpoints that external applications can call using standard HTTP methods (such as GET or POST) to start processes, query data, or trigger actions in Appian. This approach securely exposes Appian functionality to partners, mobile apps, or other systems, typically with authentication and JSON payloads.

Other options serve different purposes. A Connected System Object stores credentials and connection details for talking to external systems, not for exposing Appian services. An Integration Object defines how Appian communicates with an external system from within Appian, used for outbound or inbound calls but not for public endpoints. An Initiate Call Smart Service is used inside a process to call an external service, not to publish Appian functionality to outside callers.