[Home](./index.md) > [sip.js](./sip.js.md) > [UserAgentOptions](./sip.js.useragentoptions.md) > [sessionDescriptionHandlerFactory](./sip.js.useragentoptions.sessiondescriptionhandlerfactory.md) ## UserAgentOptions.sessionDescriptionHandlerFactory property A factory for generating `SessionDescriptionHandler` instances. Signature: ```typescript sessionDescriptionHandlerFactory?: SessionDescriptionHandlerFactory; ``` ## Remarks The factory will be passed a `Session` object for the current session and the `sessionDescriptionHandlerFactoryOptions` object.