analytics-patterns

Use the existing Pixel.fire pattern with structured event definitions.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/duckduckgo/apple-browsers/analytics-patterns
Clone the repo
git clone --depth 1 https://github.com/duckduckgo/apple-browsers

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 902 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00902
Opus 5 $0.00000 $0.00451
Sonnet 5 $0.00000 $0.00180
Haiku 4.5 $0.00000 $0.00090

Measured yesterday against content hash b79ea936cafc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

analytics-patterns scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/analytics-patterns.mdc · 156 lines

How it starts

The opening of the file, as written. The whole thing — 156 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Analytics and Pixel Patterns

Structured Pixel Events

Use the existing Pixel.fire pattern with structured event definitions:

// ✅ CORRECT - Use existing Pixel.fire with proper parameters
extension PixelEvent {
    static let featureUsed = "feature_used"
    static let performanceMetric = "performance_metric"
    static let errorOccurred = "error_occurred"
    static let userAction = "user_action"
}

// Usage examples from codebase
Pixel.fire(pixel: .webKitTerminationDidReloadCurrentTab)

Pixel.fire(pixel: .cachedTabPreviewsExceedsTabCount, withAdditionalParameters: [
    PixelParameters.tabPreviewCountDelta: "\(storedPreviews - totalTabs)"
])

Pixel.fire(pixel: .autofillLoginsSavePromptDisplayed, withAdditionalParameters: [
    PixelParameters.autofillPromptTrigger: "manual"
])

Pixel Parameters

Use the established PixelParameters constants:

// ✅ CORRECT - Use existing PixelParameters
extension PixelParameters {
    static let featureName = "fn"
    static let errorType = "et"
    static let performanceValue = "pv"
    static let userActionSource = "uas"
}

// Usage
Pixel.fire(pixel: .newFeatureUsed, withAdditionalParameters: [
    PixelParameters.featureName: "voice_search",
    PixelParameters.userActionSource: "keyboard_shortcut"
])

Performance Metrics

Track performance metrics consistently:

// ✅ CORRECT - Performance tracking pattern
final class PerformanceTracker {
    static func trackPageLoad(duration: TimeInterval, url: URL) {
        let parameters = [
            PixelParameters.duration: String(format: "%.3f", duration),
            PixelParameters.domain: url.host ?? "unknown"
        ]
        
        Pixel.fire(pixel: .pageLoadTime, withAdditionalParameters: parameters)
    }
    
    static func trackMemoryUsage(bytes: Int, context: String) {
        let parameters = [
            PixelParameters.memoryUsage: "\(bytes)",
            PixelParameters.context: context
        ]
        
        Pixel.fire(pixel: .memoryUsage, withAdditionalParameters: parameters)
    }
}

Read the full file on GitHub · 156 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 156 lines · 0 tokens per session scan A b79ea936cafc

Subscribe to this mod's changes

analytics-patterns is a cursor rule published in the GitHub repository duckduckgo/apple-browsers (252 stars, last pushed yesterday), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 902 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-01.