MS Clarity RTD Module

• Overview
• Prerequisites
• Integration
• Configuration
• Features
  • Durable Features (7) — persisted to localStorage for warm-start
  • Transient Snapshot Features (4) — computed fresh at auction time
• Output
  • Global ORTB2
  • Warm-Start (localStorage)
• Privacy
• Further Reading

Overview

The Microsoft Clarity RTD module collects behavioral signals from a self-contained DOM tracker and enriches bid requests with bucketed categorical features. Signals are compact string labels (e.g. "deep", "moderate", "high") — not raw numerics — making them directly usable in DSP targeting rules without additional processing.

Signals are written into global ORTB2 fragments, making them available to all bidders. Data is published through three complementary paths:

1. site.ext.data.msclarity — structured key-value features
2. user.data segments — ORTB2-native segments for DSPs and platforms like Microsoft Curate
3. site.keywords — keyword strings for adapters that consume keywords (e.g. AppNexus)

The module also persists signals to localStorage for warm-start support — the first auction of a new page load can use recent (≤ 30 min) signals instead of empty defaults.

The Clarity JS tag is injected by default for analytics and session-recording functionality. Set params.injectClarity: false to opt out of automatic injection. Bid-enrichment signals are computed independently from DOM events regardless of whether the Clarity tag is present.

Prerequisites

1. A Microsoft Clarity account and project — sign up at https://clarity.microsoft.com
2. Your Clarity Project ID (found in Project Settings)

Integration

1. Build the MS Clarity RTD module into the Prebid.js package with:

    gulp build --modules=rtdModule,msClarityRtdProvider,appnexusBidAdapter,msftBidAdapter
   

2. Use setConfig to instruct Prebid.js to initialize the MS Clarity RTD module, as specified below.

Configuration

This module is configured as part of the realTimeData.dataProviders object:

pbjs.setConfig({
    realTimeData: {
        auctionDelay: 200,
        dataProviders: [{
            name: 'msClarity',
            waitForIt: true,
            params: {
                projectId: 'abc123xyz',     // Required: Clarity project ID
                // injectClarity: false,    // Optional: disable auto-injection (default: true)
                targetingPrefix: 'msc'      // Optional: keyword prefix (default: 'msc')
            }
        }]
    }
});

Syntax details:

Note: The module automatically injects the Clarity JS tag unless params.injectClarity is explicitly set to false. To manage the Clarity tag yourself, set injectClarity: false and add the tag to your page before Prebid loads.

Features

The module computes 11 features in two tiers:

Durable Features (7) — persisted to localStorage for warm-start

These accumulate over the page session and are saved to localStorage for use in the first auction of subsequent page loads.

Transient Snapshot Features (4) — computed fresh at auction time

These reflect the user’s instantaneous state when a bid request fires. They are not persisted.

Output

Global ORTB2

All 11 features are written into global ORTB2 fragments, available to every bidder:

Structured features at site.ext.data.msclarity:

{
    "engagement": "high",
    "dwell": "moderate",
    "scroll": "deep",
    "frustration": "none",
    "interaction": "active",
    "readingMode": "read",
    "viewQuality": "high",
    "activityRecency": "live",
    "recentEngagement": "hot",
    "auctionAttention": "high",
    "pageMomentum": "in_reading_flow"
}

User segments at user.data:

[{
    "name": "msclarity",
    "segment": [
        { "id": "engagement_high" },
        { "id": "dwell_moderate" },
        { "id": "scroll_deep" },
        { "id": "frustration_none" },
        { "id": "interaction_active" },
        { "id": "readingMode_read" },
        { "id": "viewQuality_high" },
        { "id": "activityRecency_live" },
        { "id": "recentEngagement_hot" },
        { "id": "auctionAttention_high" },
        { "id": "pageMomentum_in_reading_flow" }
    ]
}]

Keywords at site.keywords:

msc_engagement=high,msc_dwell=moderate,msc_scroll=deep,msc_interaction=active,msc_readingMode=read,msc_viewQuality=high,msc_activityRecency=live,msc_recentEngagement=hot,msc_auctionAttention=high,msc_pageMomentum=in_reading_flow

The frustration keyword is omitted when its value is "none" to reduce noise.

Warm-Start (localStorage)

The module persists the 7 durable features to localStorage (key: msc_rtd_signals) with a 30-minute TTL. On the first auction of a new page load, if all durable features are at baseline defaults, the module falls back to the cached snapshot. Transient snapshot features are always computed fresh.

The storage manager respects consent — if localStorage access is blocked by consent management, warm-start is silently skipped.

Privacy

• All signals are page-level behavioral data (scroll, clicks, timing) — no PII is collected or transmitted.
• Signal values are bucketed categorical strings, not raw measurements, providing an additional privacy layer.
• localStorage persistence uses the consent-aware storageManager and respects TCF/GPP consent signals.
• The Clarity JS tag injection can be disabled via params.injectClarity: false.
• If projectId is not configured, the module silently disables itself.

Further Reading

• Microsoft Clarity — sign up and manage projects
• Prebid Real-Time Data Module — RTD module overview