Alerts

Alerts allow you to catch cost and quality issues before they impact your users.

You can receive notifications over Slack, trigger GitHub Actions, or call your own Webhooks.

Create an alert

Navigate to Alerts in your project and click New Alert.

Alert states

Each alert carries a severity that updates after every evaluation.

When notifications fire:

• Breach (UNKNOWN | OK → WARNING | ALERT): always notifies.
• Recovery (WARNING | ALERT → OK): always notifies.
• No data (NO_DATA ↔ WARNING | ALERT | OK | UNKNOWN): only notifies when no-data mode is Notify after sustained NO_DATA.
• Sustained severity (WARNING → WARNING, ALERT → ALERT): notifies only when Renotify is enabled.

Pause and resume

From the alert list or detail page, use the row actions menu to Pause or Resume an alert. A paused alert skips all evaluations; its severity is frozen at PAUSED. Resuming sets it back to ACTIVE and schedules the next evaluation.

Automations

Automations route alert notifications to external systems. Each automation pairs a trigger (an alert severity change) with an action (a notification sent to an external system).

Three notification channels are available:

If you would like to see another channel added, please add to the GitHub discussions.

Create an alert automation

1. Navigate to Automations and click Create Automation.
2. Select event source Alert.
3. Select an action type (Slack, Webhook, or GitHub Actions).
4. Configure the action: provide a Slack channel, a webhook endpoint URL, or a GitHub repository dispatch URL, event type, and personal access token.
5. Give the automation a name and click Save. It will appear in the Automations panel when you create or edit alerts.

Link an alert to an automation

1. Create a new alert automation or edit an existing one.
2. Create a new alert or edit an existing one.
3. Select the automation from the Automations panel found in the notifications section of the alert editor.
4. Click Save to link the alert to the selected automations.

An alert fires every linked automation whenever its severity transitions (see Alert states).

Webhook payload

Your endpoint receives a signed JSON body:

{
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "timestamp": "2024-07-10T10:30:00Z",
  "type": "monitor-alert",
  "apiVersion": "v1",
  "payload": {
    "monitorId": "monitor_abc123",
    "projectId": "proj_xyz789",
    "permalink": "https://cloud.langfuse.com/project/proj_xyz789/monitors/monitor_abc123",
    "message": {
      "title": "avg latency crossed alert threshold",
      "body": "avg latency is 1234 ms (threshold: 1000 ms) over the last 1 hour"
    },
    "severity": "ALERT",
    "timestamp": "2024-07-10T10:30:00Z",
    "fromTimestamp": "2024-07-10T09:30:00Z",
    "toTimestamp": "2024-07-10T10:30:00Z",
    "view": "observations",
    "filters": [],
    "window": "1h"
  }
}

Signature verification works identically to prompt webhooks — see Webhooks for the HMAC validation code.

GitHub Discussions