{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://jambonz.org/schema/verbs/sip:refer",
  "minVersion": "0.9.6",
  "title": "SIP Refer",
  "description": "Sends a SIP REFER request to transfer the call to another party. Initiates an attended or unattended (blind) transfer.",
  "type": "object",
  "properties": {
    "verb": {
      "const": "sip:refer"
    },
    "id": {
      "type": "string",
      "description": "An optional unique identifier for this verb instance."
    },
    "referTo": {
      "type": "string",
      "description": "The SIP URI or phone number to transfer the call to.",
      "examples": [
        "sip:alice@example.com",
        "+15085551212"
      ]
    },
    "referredBy": {
      "type": "string",
      "description": "The SIP URI to use in the Referred-By header."
    },
    "referredByDisplayName": {
      "type": "string",
      "description": "The display name to use in the Referred-By header."
    },
    "headers": {
      "type": "object",
      "description": "Custom SIP headers to include in the REFER request.",
      "additionalProperties": {
        "oneOf": [{ "type": "string" }, { "type": "number" }]
      }
    },
    "actionHook": {
      "$ref": "../components/actionHook",
      "description": "A webhook invoked when the REFER completes (or fails)."
    },
    "eventHook": {
      "$ref": "../components/actionHook",
      "description": "A webhook invoked for NOTIFY events during the REFER process, providing transfer progress updates."
    }
  },
  "required": [
    "referTo"
  ],
  "examples": [
    {
      "verb": "sip:refer",
      "referTo": "sip:alice@example.com",
      "actionHook": "/refer-complete"
    }
  ]
}