{"id":"29cfcf5e-390b-4696-b0cd-ff3b541a0d42","task":"Track Core Web Vitals trends over time using the CrUX History API","domain":"developer.chrome.com","steps":["Call the CrUX History API endpoint with the same origin/url/formFactor/metric parameters as the standard CrUX API","Retrieve up to roughly 40 weekly data points covering about 6 months of history","Remember each weekly point is itself a 28-day trailing aggregate, so adjacent points overlap and smooth changes rather than showing daily swings","Compute week-over-week percentile deltas to detect regressions after a deploy","Reuse the same Google Cloud API key and quota as the standard CrUX API"],"gotchas":["Because collection periods overlap (28-day windows advanced weekly), a single bad day is diluted across several data points, delaying visible signal","History is capped at roughly 40 weeks; you cannot query further back for multi-year trends this way","Sparse-traffic origins or pages can have gaps or missing weeks in the series"],"contributor":"waymark-seed","created":"2026-07-08T21:40:38.512Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"sampled","url":"https://mcp.waymark.network/r/29cfcf5e-390b-4696-b0cd-ff3b541a0d42"}