Call Timeouts & Duration

Overview

Sulus provides several timeout and duration settings that control how calls behave during silence, inactivity, and maximum call length. Here's an overview of each setting and how to configure it.

Idle messages use the customer.speech.timeout hook to automatically prompt users during periods of inactivity. When a user stops speaking, Sulus starts a timer and triggers configured actions when the timeout is reached.

Key configuration options:

Example — end call after 30 seconds of silence:

{
  "hooks": [
    {
      "on": "customer.speech.timeout",
      "options": { "timeoutSeconds": 10, "triggerMaxCount": 3 },
      "do": [{ "type": "say", "exact": "Are you still there?" }]
    },
    {
      "on": "customer.speech.timeout",
      "options": { "timeoutSeconds": 30, "triggerMaxCount": 3 },
      "do": [
        { "type": "say", "exact": "I'll be ending the call now." },
        { "type": "tool", "tool": { "type": "endCall" } }
      ]
    }
  ]
}

Idle messages are automatically disabled during tool calls and warm transfers to avoid interrupting system processes.

Calls are automatically terminated when they reach maxDurationSeconds, resulting in the exceeded-max-duration ended reason. This is configured on the assistant and sets a hard cap on how long any single call can last.

The silence-timed-out ended reason is triggered when no speech is detected for the configured silence timeout duration. This is distinct from idle messages — it ends the call outright rather than prompting the user.

For AI-managed warm transfers, you can configure silenceTimeoutSeconds (default 30 seconds) on the Transfer Assistant to automatically end the call after a specified period of silence. This prevents idle calls from lingering and saves costs.

customerJoinTimeoutSeconds sets the maximum time users have to join a web call before it's automatically terminated. If users don't complete the join process (network connection, microphone permissions, WebRTC setup) within the timeout, the call ends with assistant-did-not-receive-customer-audio.

Example configuration:

curl -X POST "https://api.sulus.ai/assistant" \
     -H "Authorization: Bearer $SULUS_API_KEY" \
     -H "Content-Type: application/json" \
     -d '{
       "name": "My Assistant",
       "customerJoinTimeoutSeconds": 30
     }'

In summary, Sulus gives you fine-grained control over call timeouts at multiple levels: idle message prompts via hooks, hard call duration limits, silence-based call termination, warm transfer silence handling, and web call join timeouts. Combining these settings lets you optimize both user experience and resource usage.