Voice Alerts

Overview

A voice alert watches one call metric over a rolling window and notifies you when it crosses a threshold: "tell me when the connect rate drops below 40% over the last hour", or "when p95 turn latency goes above 2,500 ms over 15 minutes". Scope an alert to one agent with bot_id, or leave it workspace-wide.

Alerts are evaluated about once a minute. Firing is edge-triggered: a metric that stays bad notifies once, not once per evaluation. The alert re-arms only after the metric recovers, and cooldown_minutes stops a flapping metric from notifying again too soon.

Authentication

Authorization: Bearer cm_your_api_key

Base URL: https://api.callmissed.com. Errors are {"detail": "..."}.

Metrics

• Every *_rate metric is a fraction: 0.25 means 25%. A rate threshold outside 0..1 is rejected with 422 ("<metric> is a fraction — threshold must be between 0 and 1 (0.25 means 25%)"). Non-rate thresholds must be >= 0.
• Rate metrics need at least 5 calls or sessions in the window before they produce a reading. Below that there is no reading: the alert is not evaluated, does not fire, and does not clear.

The alert object

{
  "id": "a1e2c3d4-5f60-4718-8293-a4b5c6d7e8f9",
  "tenant_id": "a0b1c2d3-4455-6677-8899-aabbccddeeff",
  "bot_id": null,
  "name": "Connect rate dropped",
  "metric": "connect_rate",
  "comparison": "below",
  "threshold": 0.4,
  "window_minutes": 60,
  "channels": ["email", "webhook"],
  "enabled": true,
  "cooldown_minutes": 60,
  "is_firing": false,
  "last_value": 0.62,
  "last_fired_at": null,
  "last_evaluated_at": "2026-09-30T10:14:00+00:00"
}

GET /api/v1/voice-alerts

Every alert in your workspace, newest first. No parameters.

curl https://api.callmissed.com/api/v1/voice-alerts \
  -H "Authorization: Bearer cm_your_api_key"

Returns an array of alert objects.

POST /api/v1/voice-alerts

Creates an alert. Returns 201 with the alert object.

curl -X POST https://api.callmissed.com/api/v1/voice-alerts \
  -H "Authorization: Bearer cm_your_api_key" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Connect rate dropped",
    "metric": "connect_rate",
    "comparison": "below",
    "threshold": 0.4,
    "window_minutes": 60,
    "channels": ["email", "webhook"]
  }'

A workspace can hold at most 50 alerts; the 51st returns 409 Alert limit reached (50).

PUT /api/v1/voice-alerts/{alert_id}

Partial update — send only the fields you want to change. Accepts name, comparison, threshold, window_minutes, channels, enabled and cooldown_minutes, with the same constraints as create. metric and bot_id are fixed; create a new alert to change them.

Changing threshold, comparison or window_minutes changes what the alert means, so it resets is_firing to false.

curl -X PUT https://api.callmissed.com/api/v1/voice-alerts/a1e2c3d4-5f60-4718-8293-a4b5c6d7e8f9 \
  -H "Authorization: Bearer cm_your_api_key" \
  -H "Content-Type: application/json" \
  -d '{"threshold": 0.35, "cooldown_minutes": 120}'

Returns the updated alert object.

DELETE /api/v1/voice-alerts/{alert_id}

Deletes the alert. Returns 204 with no body.

Notifications

Webhook deliveries are signed and retried exactly like every other event. The body:

{
  "event": "voice_alert.triggered",
  "data": {
    "alert_id": "a1e2c3d4-5f60-4718-8293-a4b5c6d7e8f9",
    "name": "Connect rate dropped",
    "metric": "connect_rate",
    "comparison": "below",
    "threshold": 0.4,
    "value": 0.31,
    "window_minutes": 60,
    "bot_id": null,
    "scope": "workspace"
  },
  "timestamp": "2026-09-30T10:15:00+00:00"
}

scope is "bot" when the alert has a bot_id, otherwise "workspace". A failure on one channel does not block the other.

Errors