System tools - Cartesia Docs

System tools are built-in actions configured directly on an agent. config.system_tools currently supports three slots: end_call, send_dtmf, and transfer_to_number.

Tools page in the Playground with End call, Send keypad tones, and Transfer call toggles — Turn system tools on from the Tools page in the Playground.

{
  "config": {
    "system_tools": {
      "end_call": {
        "description": "End the call after the caller explicitly says goodbye.",
        "pre_tool_speech": "force"
      },
      "send_dtmf": null,
      "transfer_to_number": {
        "description": null,
        "pre_tool_speech": "auto",
        "transfers": [
          {
            "destination": {
              "type": "phone",
              "phone_number": "+14155550100"
            },
            "condition": "The caller asks to speak with billing."
          }
        ]
      }
    }
  }
}

Reads return all three slots. A disabled slot is null. On PATCH:

Omit a slot to leave it unchanged.
Send null to disable it.
Send the config object to enable or update any slot settings.

An empty object enables end_call or send_dtmf with defaults. Set description to direct when the model should invoke the tool. For example, require an explicit goodbye before ending a call or prevent the agent from hanging up when it reaches voicemail. Set it to null to use the built-in description. pre_tool_speech controls whether the agent speaks before acting. auto lets the agent decide; force asks it to speak first.

End call

Allows the agent to end a call when the conversation is complete or the caller asks to hang up.

Send DTMF

Allows the agent to send one or more keypad tones, such as 12#, while navigating a phone menu. Supported tones are 0 through 9, *, and #.

Transfer to number

Transfers a phone call to an E.164 phone number or a SIP URI. You can configure up to 16 distinct destinations, each with a condition that tells the model when to use it.

{
  "transfers": [
    {
      "destination": { "type": "phone", "phone_number": "+14155550100" },
      "condition": "The caller has a billing or payment question."
    },
    {
      "destination": { "type": "sip_uri", "sip_uri": "sip:user@host" },
      "condition": "The caller reports a technical problem with their device."
    },
    {
      "destination": { "type": "phone", "phone_number": "+14155550102" },
      "condition": "The caller asks for a person and no other destination applies."
    }
  ]
}

In the Playground, open Tools, enable Transfer call, and choose Phone number or SIP URI for each rule’s Destination. Set type to "sip_uri" and provide sip_uri in the form sip:user@host or sips:user@host, using a lowercase scheme and including both a user and a host.

SIP URI transfers require a phone call routed through a SIP trunk.

​End call

​Send DTMF

​Transfer to number

End call

Send DTMF

Transfer to number