action callfire_start_voice_broadcast { label: "Start voice broadcast" description: "Start a voice broadcast" provider: callfire method: POST path: "/calls/broadcasts/{id}/start" encoding: json input: { type: "object" properties: { id: { type: "integer" format: "int64" } } required: ["id"] additionalProperties: false } output: { type: "object" additionalProperties: true } }