[Home](./index.md) > [sip.js](./sip.js.md) > [MessageUserAgentClient](./sip.js.messageuseragentclient.md) > [(constructor)](./sip.js.messageuseragentclient._constructor_.md) ## MessageUserAgentClient.(constructor) Constructs a new instance of the `MessageUserAgentClient` class Signature: ```typescript constructor(core: UserAgentCore, message: OutgoingRequestMessage, delegate?: OutgoingRequestDelegate); ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | core | UserAgentCore | | | message | OutgoingRequestMessage | | | delegate | OutgoingRequestDelegate | |