Example

{
  "type": "session.updated",
  "event_id": "evt_updated_001",
  "client_event_id": "evt_update_001",
  "session": {
    "id": "live_def456",
    "model": "gpt-live-1",
    "status": "active",
    "expires_at": 1788555600,
    "instructions": "Help the caller plan a restaurant reservation. Confirm details before booking.",
    "input": [],
    "audio": {
      "format": {
        "type": "audio/pcm",
        "rate": 24000
      },
      "output": {
        "voice": "marin"
      }
    },
    "delegation": {
      "type": "responses",
      "responses": {
        "model": "gpt-6-astra",
        "instructions": "Check restaurant availability. Ask before confirming a booking.",
        "max_output_tokens": 1024,
        "tools": []
      }
    }
  }
}

session.input_audio.muted

Returned when a session.input_audio.mute command is accepted. Input audio is no longer sent to the model; sideband audio reflection continues.