ga4-audit

GA4 Audit

A one-time audit of a Google Analytics 4 property — configuration and data quality. GA4 collects data the moment the tag fires, but most properties quietly leak trust: unmarked key events, PII in parameters, no Ads link, (not set) traffic. This skill finds those before they corrupt a quarter of reporting.

Requires: Cogny Agent subscription ($9/mo) — Sign up

Prerequisites Check

If mcp__cogny__google_analytics_4__tool_get_property is not available:

This skill requires Cogny's Google Analytics 4 MCP server.

Sign up at https://cogny.com/agent
Connect your GA4 property
Add Cogny to your .mcp.json (see the repo README)
Restart Claude Code


Stop here if the tools are missing.

## Usage

`/ga4-audit` — full property audit
`/ga4-audit config` — property + stream + link settings only
`/ga4-audit events` — events, key events, custom dimensions only
`/ga4-audit data-quality` — `(not set)`, PII, anomaly checks only

## Steps

### 1. Property discovery

tool_list_account_summaries tool_get_property (property_id)


Record: time zone, currency, industry category, **data retention setting**, and
property type. Flag data retention left at the 2-month default — it should be 14
months so year-over-year exploration works.

### 2. Data streams

tool_list_data_streams (property_id)


Flag:
- Multiple web streams for one site (splits data, double-counts users)
- Enhanced measurement off, or measuring events the team doesn't actually want
- Missing iOS/Android streams for a business that has apps

### 3. Key events (conversions)

tool_list_conversion_events (property_id)


Flag:
- **No key events configured** — Ads bidding and GA4 reporting both lose their anchor
- Key events marked on noisy automatic events (`page_view`, `scroll`) — inflates the
  conversion count and misleads everyone
- Obvious business goals *not* marked as key events (e.g. `generate_lead`, `purchase`,
  `sign_up`)
- More than ~10–15 key events — when everything is a conversion, nothing is

### 4. Custom dimensions & metrics

tool_list_custom_dimensions (property_id) tool_list_custom_metrics (property_id) tool_get_metadata (property_id)


Flag:
- Event parameters collected by the tag but **never registered** as custom dimensions
  (the data is invisible in reports) — compare `get_metadata` against what the streams
  send
- Approaching the 50 event-scoped / 25 user-scoped dimension limits
- High-cardinality registered dimensions (timestamps, IDs) — they cause `(other)` rows

### 5. Traffic & data-quality report

tool_run_report (property_id, last 30 days, dimensions: sessionDefaultChannelGroup, sessionSource, sessionMedium, metrics: sessions, conversions, totalUsers)


Flag:
- A large `Unassigned` or `(not set)` share — broken UTMs or tagging gaps
  (point the user to `/utm-builder`)
- A `Direct` share above ~40% — usually lost referrer data or missing tags
- Self-referrals (your own domain as a source) — needs an unwanted-referral filter
- Internal traffic visible in reports — no internal-traffic filter applied

### 6. PII & policy check

Scan event and parameter names from `get_metadata` for anything that could carry
personal data — `email`, `phone`, `user_email`, full names, raw addresses in
parameters or in the page path / query string.

🔴 PII in GA4 violates Google's policy and risks the property being deleted. Flag it
as critical and name the exact parameter.

### 7. Integrations

Flag:
- **No Google Ads link** — conversions can't flow to Ads for bidding (check with the
  user; the link isn't always API-visible)
- No BigQuery export — recommend it for any property that wants raw-data analysis
  (`/ga4-bigquery-schema` covers the schema)
- Search Console not linked

### 8. Score and report

GA4 Audit — [Property Name] GA4 Health Score: X/100

Score breakdown: Configuration ...... X/20 (streams, retention, time zone) Key events ......... X/25 (the reporting + bidding anchor) Custom dimensions .. X/15 Data quality ....... X/25 ((not set), Direct, self-referrals) Compliance ......... X/15 (PII, internal traffic)

🔴 Critical — PII collected, no key events, retention at 2 months 🟡 Important — unregistered dimensions, high (not set), no Ads link 🟢 Optimization — BigQuery export, enhanced measurement tuning

Top 3 Actions:

[Highest impact]
...
...


### 9. Record findings

```json
{
  "title": "Email address captured in GA4 'page_location' — policy violation",
  "body": "The checkout-success URL includes ?email=… and GA4 stores it in page_location and page_path. Google policy prohibits PII in Analytics and can delete the property. Strip the parameter at the tag, or redact it before the event fires.",
  "action_type": "data_quality",
  "expected_outcome": "PII removed from collection; property compliant",
  "estimated_impact_usd": 0,
  "priority": "critical"
}

Action types: tracking_configuration, conversion_setup, data_quality, custom_dimension, integration, compliance.

Critical rules

PII is always critical. Flag it loudly and name the parameter.
Key events are the anchor — for GA4 reporting and for Ads bidding. Weight them.
Quote real numbers: retention months, (not set) %, dimension counts.
Read-only. Never change property settings — surface and recommend.

About this skill

Prerequisites Check

Critical rules