GA4 Site Blood Test

GA4 Site Blood Test runs a health check on your website the way a blood panel works: a fixed set of measurements, compared against reference ranges, producing a score and a list of what is out of range. It pulls engagement and conversion metrics from Google Analytics 4 broken down by device — bounce rate, average session duration, session conversion rate, pageviews per session, engagement rate — compares each against industry reference bands, computes an overall health score from 0 to 100, and surfaces the critical and warning findings. The mobile-versus-desktop gap is derived as its own signal, which is usually where a site's real problem hides: a desktop-healthy site with a broken mobile funnel averages out to fine. Every measurement and every threshold is deterministic. A language model writes the prescription — what to do about each finding — and is never allowed to invent or alter a metric. Without a model configured it falls back to a template prescription and the diagnosis is unchanged. It then goes one step further than most analytics tools: a rule-based engine matches each finding to real B2B SaaS products that typically address it, so a high mobile bounce rate comes back with ranked vendor candidates rather than just a red number. Each part is callable alone. `get_metrics_panel` returns the raw per-device panel. `get_worst_pages` ranks your worst offenders by bounce rate. `analyze_findings` diagnoses a panel you already have with no model call. `get_metrics_thresholds` shows the reference bands so you can check the scoring against your own benchmarks. Connecting GA4 needs a Google service account with viewer access to the property. Built for growth marketers, web teams and anyone who has been asked why conversion dropped and needs an answer with numbers behind it.