How to Eliminate False Alerts

Experiencing frequent false alerts is a common challenge in website monitoring. This guide systematically addresses the issue, helping you eliminate noise and ensure alerts are triggered only by meaningful changes.

Why False Alerts Occur

False alerts usually stem from:

• Incomplete page loading when monitored
• Dynamic content (timestamps, ads, counters)
• Layout or formatting changes triggering irrelevant alerts

Each issue can be systematically resolved by following the steps outlined below.

Step 1: Identify the Source of False Alerts - View Change History

Before addressing false alerts, pinpoint the exact cause. Keep in mind that an alert is triggered when a change is detected.

Steps to Diagnose - Find Changed Content:

• Open your Watchlist.
• Navigate to Change History for the affected monitor. See Highlighted Changes
• Review the highlighted changes: additions appear in green, deletions appear in red (if the option to show Deleted is enabled). You can switch to Text mode for a quick and simplified view. Following screenshot shows that new slots have been added to the monitored page:

Common reasons

1. Page is partially loaded. Proceed to Step 2.
2. Page has noisy content that should not be monitored. It can be irrelevant content (such as timestamps or view counters). Proceed to Step 3 to refine your selections. 3.Page content varies by location. Proceed to Step 4.
3. The content needs to be monitored but needs to trigger alert only if a certain criteria is met. Proceed to Step 5.

Step 2: Allow Pages to Load Completely

Incomplete page loading often triggers false alerts (e.g., empty to populated text changes).

Solution: Introduce a delay before monitoring.

• Go to your monitor’s Options.
• Click the gear icon next to “Open Webpage Selector”.
• Set “Wait for duration” between 5-10 seconds (increase to 20 seconds for slower pages).

Also see Config Options.

When to increase delays:

• JavaScript-intensive sites (SPAs, dynamic content) that takes more time to render content.

Additional dynamic page settings:

• Disable JavaScript if JS rendering is not required to view main content.

Step 3: Monitor Only Essential Content

Reducing noise means focusing exclusively on meaningful content.

Visual Selector

• Click “Open webpage selector”. See using Visual Selector
• Deselect volatile elements (timestamps, counters, ads, widgets) by clicking (they turn red).
• Verify the updated preview ensures only critical content is monitored.

Step 4: Use local device to Monitor Location Restricted Pages

If a page’s change history shows different data depending on where it’s accessed from, use local monitor. You will need Distill’s browser extension or the desktop app to run pages locally.

Note: Use a proxy or dedicated cloud device to monitor geo-restricted pages in the cloud.

Step 5: Add Conditions to Refine Alerts

Conditions filter alerts based on specific criteria.

Example conditions:

• Product availability: Added Text contains "In Stock"
• Price drop alerts: has number less than 399
• Ignore minor layout changes: Added text length is greater than 20

Adding Conditions:

• Open monitor Options.
• Select “Add Condition”.
• Choose the content type (e.g., Added Text, Net Added, Text).
• Define criteria, save, and test.

Condition scope:

• Local conditions: Specific to individual monitors.
• Global conditions: Apply universally across monitors (via Watchlist ☰ menu).

Step 6: Validate Your Monitoring Setup

Ensure your configuration reliably filters false positives:

Testing checklist:

• Double-check test: Two immediate “Check Now” runs shouldn’t trigger alerts.
• Condition Test: Try testing conditions with different previous text and text datasets. See: Testing Conditions.
• Change Simulation: From the Options page, change the monitor’s URL and click Check Now. This is useful when monitoring a product marked “out of stock.” Replacing the URL with one for a product in stock should trigger an alert and confirm that your selector is correct.

Quick Troubleshooting Guide

The Proven Three-Step Formula

After extensive experience, the following method significantly reduces false alerts:

1. Wait: Allow pages sufficient loading time.
2. Watch: Monitor only stable, relevant content.
3. Filter: Define clear, relevant conditions for alerts.

For further assistance, visit our community forum to address specific issues or scenarios.