Observability

Alerts

This topic explains how to set alerts for LaunchDarkly’s observability features. Alerts are a way to keep members of your organization aware of what is happening in your application. You can set alerts based on sessions, errors, logs, or traces, or when important conditions are met.

LaunchDarkly supports two alert types:

  • Constant alerts trigger when a metric crosses a value threshold you define (for example, error count above 100).
  • Anomaly alerts trigger when LaunchDarkly detects unusual behavior or patterns in your observability data.

Alerts can send one or more notifications when the alert trigger condition occurs:

  • Member notifications send an email to each LaunchDarkly member added to the alert notification. If you have configured the LaunchDarkly Slack app, member notifications are also sent through Slack.

  • Slack notifications send alert notifications to configured Slack channels.

  • Webhook notifications send alert messages to one or more URLs. When the alert trigger condition occurs, LaunchDarkly sends a POST request to configured URLs using a message of the following format:

    1{
    2  "Event": "LOGS_ALERT",
    3  "AlertName": "too many errors!",
    4  "Query": "level=error",
    5  "Count": 10,
    6  "StartDate": "2025-10-10T17:38:23.439580358Z",
    7  "EndDate": "2025-10-10T18:08:23.439580358Z",
    8  "Function": "Count",
    9  "FunctionColumn": "",
    10  "Threshold": 1,
    11  "BelowThreshold": false,
    12  "LogsURL": "logs?query=&startDate=2025-10-10T17%3A38%3A23Z&endDate=2025-10-10T18%3A08%3A23Z"
    13}

For member and Slack notifications, you can configure the text of the notification message using variables populated from the alert configuration. To learn more, read Create an alert.

Prerequisites

To use alerts in LaunchDarkly, you must enable observability features to instrument logs, traces, sessions, errors, product analytics events, or observability metrics. To learn more, read Observability.

To configure Slack notifications for alerts:

View alerts

All configured alerts appear as entries on the main Alerts page in the Telemetry section. Each row of the Alerts table shows the alert name, status, configured notification types, and a condensed graph of alert activity.

The Alerts table.

The Alerts table.

To view details for an individual alert, click its name in the Alert name column. The detail page shows the number of active alerts, as well as the last time LaunchDarkly checked the alert trigger conditions. A graph displays the alert threshold values measured over the indicated time period.

The alert detail page.

The alert detail page.

If you have enabled Vega, the detail page provides the option to enable Vega auto-remediation for the alert. If auto-remediation was already enabled, the detail page displays remediation results.

Create an alert

To add a new alert based on your LaunchDarkly observability data:

  1. Open the Telemetry section and navigate to the Alerts list.
  2. Click Create alert.
  3. Enter an Alert title.
  4. Select a Source to query. You can add alerts based on data from any of the following:
    • logs
    • traces
    • sessions
    • errors
    • events
    • observability metrics
    Alert events come from session replay

    In the alert configuration, “events” refer to track, click, and navigate events that occur in a session replay.

  5. (Optional) Click + Add filters to filter data points from your selected source before aggregating. For example, if you only want to generate alerts from data in the production environment, create a filter for the environment attribute and use search operators to define the environments to display. To learn more about the filter syntax, read Search specification.
  6. (Optional) Select a Function from the menu to aggregate the source data. If you choose a function that requires a parameter, such as “Min,” select the attribute to use as well. Functions are not available for all sources.
  7. (Optional) Click Group by and select an attribute to use for grouping your query results into separate series. For example, you might group your log results by level. Grouping is not available for all sources.
  8. Use the Type menu in the Triggers section to choose the type of trigger that generates the alert: Constant (threshold-based) or Anomaly (detects unusual patterns in your data).
  9. Configure the alert conditions based on the trigger type you selected. To learn more, read Constant alert configuration or Anomaly alert configuration.
  10. (Optional) Use the Notifications section to customize the markdown message associated with alert notifications. Use the Variables menu to insert variables that correspond to alert configuration options, such as the threshold or cooldown settings.
  11. (Optional) Click + Add notification and select the destinations for notifications when the threshold is met or an anomaly is detected.
  12. (Optional) If you have enabled Vega, click the Auto investigation toggle to enable automatic investigation after the trigger condition creates an alert. Then configure optional investigation options as necessary:
    • Investigation cooldown: Enter the amount of time to wait before subsequent investigations start for the same alert.
    • Agent mode: Select whether the investigation should provide suggestions only or create GitHub pull requests to address the problem. To learn more, read Vega for auto remediation.
    • Custom context: Add natural-language instructions to use as context when remediating this alert.
  13. Click Save.

Constant alert configuration

Follow these steps to trigger an alert using a constant threshold:

  1. Select Above or Below from the Condition menu to configure whether LaunchDarkly generates an alert when conditions are observed above or below your threshold.
  2. Enter the numerical value for the Alert threshold.
  3. (Optional) Click + Warning threshold to define an alternative threshold value that generates a warning rather than an alert.
  4. (Optional) Click ^ Advanced threshold settings to configure any of the following settings:
    • Alert window: Select the time range during which data points are searched and aggregated. Shorter windows can help if you need to be alerted quickly about an issue, while longer windows can help reduce noise by aggregating across a longer time range.
    • Cooldown: Select the amount of time that must pass after an initial notification, before LaunchDarkly generates an additional notification for the event. If the alert condition still exists after the cooldown, LaunchDarkly sends another notification.
    • Evaluation delay (min): Enter the number of minutes to delay evaluating the alert after the alert window closes. Using an evaluation delay helps you to capture relevant alert data that may arrive late from the configured event source. The configuration panel shows a caution icon when data from the selected source has been received with regular delays. Hover on the icon to view a percentile breakdown of delay durations.

The configuration panel for an alert, showing ingest delay.

The configuration panel for a constant alert, showing ingest delay.

Anomaly alert configuration

Follow these steps to trigger an alert with an anomaly threshold:

  1. Select Above or Below from the Condition menu to configure whether LaunchDarkly generates an alert when conditions are observed above or below your threshold.
  2. Set the Alert threshold to the confidence level of the anomaly prediction (a higher confidence is more likely to be an anomaly).
  3. (Optional) Click ^ Advanced threshold settings to configure any of the following settings:
    • Alert window: Select the time range during which data points are searched and aggregated. Shorter windows can help if you need to be alerted quickly about an issue, while longer windows can help reduce noise by aggregating across a longer time range.
    • Cooldown: Select the amount of time that must pass after an initial notification, before LaunchDarkly generates an additional notification for the event. If the alert condition still exists after the cooldown, LaunchDarkly sends another notification.
    • Evaluation delay (min): Enter the number of minutes to delay evaluating the alert after the alert window closes. Using an evaluation delay helps you to capture relevant alert data that may arrive late from the configured event source. The configuration panel shows a caution icon when data from the selected source has been received with regular delays. Hover on the icon to view a percentile breakdown of delay durations.

The configuration panel for an alert.

The configuration panel for an anomaly alert.

Manage alerts

You can manage individual alerts from the Alerts list.

Edit an alert

To change the configuration for an alert:

  1. Navigate to Alerts in the left sidebar. A list of all alerts appears.
  2. Find the alert you want to edit, then select Edit alert from its three-dot overflow menu. The “Edit” page appears.
  3. Update the alert configuration as necessary.
  4. Click Save.

Enable or disable an alert

To enable or disable a configured alert:

  1. Navigate to Alerts in the left sidebar. A list of all alerts appears.
  2. Find the alert you want to enable or disable, then select Enable alert or Disable alert from its three-dot overflow menu.

Only enabled alerts send notifications.

Delete an alert

To delete an alert:

  1. Navigate to Alerts in the left sidebar. A list of all alerts appears.
  2. Find the alert you want to delete, then select Edit alert from its three-dot overflow menu. The “Edit” page appears.
  3. Click Delete alert.