> For the complete documentation index, see [llms.txt](https://prosbcdocs.telcobridges.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prosbcdocs.telcobridges.com/telecom-references/developer-reference/caf/caf-call-interface.md). # CAF Call interface This interface is used as the API to an object that can handle multiple call legs. It is primarily used by other CAF modules such as Behaviors to interact with the call management object without explicitly knowing its class definition. This interface is particularly useful since a system designer can completely replace the default call handling class (GRP\_DOC\_CALL\_MANAGEMENT\_CAF\_CALL) **(LINK?)** by a custom class, and still benefit from all the behaviors from the Toolpack modules (e.g., ring-back-tone, voicemail-fallback, etc.). ### Usage This interface does not define the behavior of the class or its implementation. This is specifically what makes this interface so useful, since applications such as Telephony Application could be easily be modified by providing a new, custom-made, call handling class by simply changing one line in the application. All remaining code of the application does not need to be altered as it never makes any reference to the class since it always uses interface pointers. Return to the Toolpack [User Guide](https://prosbcdocs.telcobridges.com/tmedia-documentation/other-pages/getting-around-the-portal/user-guide) --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://prosbcdocs.telcobridges.com/telecom-references/developer-reference/caf/caf-call-interface.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.