# Read the checkout funnel in GA4

> Tier: recipe. Operating recipe: real tool sequence, core rules, known traps.

The checkout-specific funnel with ecommerce diagnostics first, because this is where measurement gaps cost most.

**Intent.** Cart to purchase, the retail money path.

## When to use

- Retail weekly.
- After checkout releases.

## When not to use

- No specific contraindication beyond the preconditions below.

## Sources

Required: Google Analytics 4

## Preconditions

- The account is ticked in the dashboard, confirmed via list_accounts.

## Inputs

- `window`: Analysis window. Default: last 30 days.

## Procedure

1. Check ecommerce measurement health. — tools: `ga4_get_ecommerce_diagnostics`
2. Run cart → checkout → shipping → payment → purchase, cut by device. — tools: `ga4_run_advanced_funnel_report`

## Decision rules

- **When** Payment-step drop moved after a release → **conclude** Highest-severity product finding on the site: date it against the deploy.

## Evidence requirements

- Every figure carries its account, metric and window.
- Anything below a readable sample size is reported as unjudged, not as zero.

## Human approval boundary

- The readout changes nothing. Any change it motivates goes through Safe Writes: preview, human confirmation, then apply.

## Failure modes

- Payment redirects to PSPs break session continuity: configure referral exclusions before believing the step.

## Output

- **Readout**: The figures, with windows and accounts named.
- **Flags**: What deserves a deeper skill or a human decision.

## Related

- Skill: [funnel-analysis](https://www.getmcpads.com/skills/funnel-analysis.md)
- Skill: [tracking-audit](https://www.getmcpads.com/skills/tracking-audit.md)