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6.36 Core Web Vitals / Speed Optimization / Performance AI-Readiness

200 checks in Schema, Local, Trust, Deep Audit. Automated Its subsection has a live automated checker in the engine.

Core Web Vitals — LCP, INP, CLS Baseline Validation

ID	Check	Passes when	Weight	Runs
6.36.01	Validate LCP element identifiable	Identifiable	Critical	Deterministic
6.36.02	Validate LCP < 2.5s (or fastest possible)	Optimal	Critical	Deterministic
6.36.03	Validate LCP resource preloaded	Preloaded	Critical	Deterministic
6.36.04	Validate LCP element not lazy‑loaded	Not lazy	Heavy	Deterministic
6.36.05	Validate LCP element in initial viewport	In‑viewport	Heavy	Deterministic
6.36.06	Validate LCP resource optimized (WebP/AVIF)	Optimized	Medium	Deterministic
6.36.07	Validate LCP element not blocked by JS	Unblocked	Medium	Deterministic
6.36.08	Validate INP < 200ms (or as low as feasible)	Responsive	Medium	Deterministic
6.36.09	Validate CLS < 0.1	Stable	Medium	Deterministic
6.36.10	Validate CLS events mapped & documented	Documented	Medium	Deterministic

Render-Path Optimization — Critical CSS, JS Order, Blocking Reduction

ID	Check	Passes when	Weight	Runs
6.36.11	Validate no render‑blocking JS in <head>	None	Heavy	Deterministic
6.36.12	Validate critical CSS inlined	Inlined	Heavy	Deterministic
6.36.13	Validate deferred JS loading	Deferred	Heavy	Deterministic
6.36.14	Validate unused CSS removed	Clean	Medium	Deterministic
6.36.15	Validate unused JS removed	Clean	Medium	Deterministic
6.36.16	Validate async scripts used where possible	Async	Medium	Deterministic
6.36.17	Validate preload hints for key resources	Present	Medium	Deterministic
6.36.18	Validate preconnect hints for third‑party domains	Present	Medium	Deterministic
6.36.19	Validate CSS delivery minimized to critical blocks	Minimal	Medium	Deterministic
6.36.20	Validate hydration load not delaying LCP	Safe	Medium	Deterministic

Image Optimization — Formats, Sizes, Responsive, Dpr

ID	Check	Passes when	Weight	Runs
6.36.21	Validate all images use WebP or AVIF where supported	Optimized	Critical	Deterministic
6.36.22	Validate responsive images (srcset, sizes)	Responsive	Heavy	Deterministic
6.36.23	Validate no oversized images relative to container	Correct	Heavy	Deterministic
6.36.24	Validate hero images compressed	Compressed	Heavy	Deterministic
6.36.25	Validate DPR‑variants exist (1x, 2x)	Present	Medium	Deterministic
6.36.26	Validate lazy‑loading applied to below‑fold images	Lazy	Medium	Deterministic
6.36.27	Validate no duplicate image downloads	None	Medium	Deterministic
6.36.28	Validate next‑gen formats served automatically	Served	Medium	Deterministic
6.36.29	Validate image CDN configured	Configured	Medium	Deterministic
6.36.30	Validate aspect‑ratio attributes set	Set	Medium	Deterministic

Video Optimization — Embeds, Streaming, Preload, Poster Frames

ID	Check	Passes when	Weight	Runs
6.36.31	Validate videos lazy‑loaded	Lazy	Heavy	Deterministic
6.36.32	Validate video preload=“metadata”	Efficient	Heavy	Deterministic
6.36.33	Validate poster frames optimized	Optimized	Heavy	Deterministic
6.36.34	Validate no auto‑play without need	Controlled	Medium	Deterministic
6.36.35	Validate embed code does not load heavy scripts	Light	Medium	Deterministic
6.36.36	Validate streaming served from CDN	CDN	Medium	Deterministic
6.36.37	Validate video dimensions responsive	Responsive	Medium	Deterministic
6.36.38	Validate no heavy third‑party JS on video pages	Minimal	Medium	Deterministic
6.36.39	Validate mobile fallback for video	Present	Medium	Deterministic
6.36.40	Validate transcripts available	Available	Medium	Deterministic

Font Optimization — Loading Strategies, Weights, Swap

ID	Check	Passes when	Weight	Runs
6.36.41	Validate font-display: swap used	Swap	Heavy	Deterministic
6.36.42	Validate no excessive font weights loaded	Minimal	Heavy	Deterministic
6.36.43	Validate no base64‑embedded large fonts	Clean	Heavy	Deterministic
6.36.44	Validate system fonts used when appropriate	Appropriate	Medium	Deterministic
6.36.45	Validate preloading key font files	Preloaded	Medium	Deterministic
6.36.46	Validate WOFF2 used as primary format	WOFF2	Medium	Deterministic
6.36.47	Validate font subsets served	Subsetted	Medium	Deterministic
6.36.48	Validate icon fonts replaced with SVG	SVG	Medium	Deterministic
6.36.49	Validate fallbacks present	Present	Medium	Deterministic
6.36.50	Compute partial Performance score for Chunk 1	Complete	Critical	Deterministic

Script Optimization — Size, Execution Cost, Deferred Logic

ID	Check	Passes when	Weight	Runs
6.36.51	Validate JS bundle size < 150KB (or minimized)	Minimized	Heavy	Deterministic
6.36.52	Validate third‑party scripts loaded after user interaction	Deferred	Heavy	Deterministic
6.36.53	Validate JS execution time < 200ms main thread	Fast	Heavy	Deterministic
6.36.54	Validate expensive scripts removed or replaced	Cleaned	Medium	Deterministic
6.36.55	Validate hydration minimized for framework pages	Minimized	Medium	Deterministic
6.36.56	Validate long tasks (<50ms) minimized	Minimized	Medium	Deterministic
6.36.57	Validate execution waterfall not blocking paint	Unblocked	Medium	Deterministic
6.36.58	Validate side‑effect scripts separated	Separated	Medium	Deterministic
6.36.59	Validate module scripts used (<script type="module">)	Modern	Medium	Deterministic
6.36.60	Validate JS caching effective	Cached	Medium	Deterministic

Server Performance — TTFB, Response Time, Edge Delivery

ID	Check	Passes when	Weight	Runs
6.36.61	Validate TTFB < 200ms	Fast	Critical	Deterministic
6.36.62	Validate server located near primary audience	Near	Heavy	Deterministic
6.36.63	Validate CDN used effectively	Effective	Heavy	Deterministic
6.36.64	Validate caching headers correct (Cache-Control, ETag)	Correct	Heavy	Deterministic
6.36.65	Validate compression (Gzip/Brotli) enabled	Enabled	Medium	Deterministic
6.36.66	Validate no unnecessary server redirects	None	Medium	Deterministic
6.36.67	Validate keep‑alive good (persistent connections)	Persistent	Medium	Deterministic
6.36.68	Validate CDN edge caching high hit‑ratio	High	Medium	Deterministic
6.36.69	Validate no geographic latency spikes	Stable	Medium	Deterministic
6.36.70	Validate HTTP/3 supported	Supported	Medium	Deterministic

AI-Performance Readiness — Read Speed, Token Determ

ID	Check	Passes when	Weight	Runs
6.36.71	Validate HTML generated deterministically each load	Deterministic	Critical	Deterministic
6.36.72	Validate AI‑agents can load critical content in <1s	Fast	Heavy	Deterministic
6.36.73	Validate page consumable without JS	Consumable	Heavy	Deterministic
6.36.74	Validate headers stable for AI crawlers	Stable	Heavy	Deterministic
6.36.75	Validate token order consistent across crawls	Consistent	Medium	Deterministic
6.36.76	Validate DOM tree stable across repeated loads	Stable	Medium	Deterministic
6.36.77	Validate large components prefetched only when needed	Controlled	Medium	Deterministic
6.36.78	Validate no randomized elements (ads, popups) affect HTML	None	Medium	Deterministic
6.36.79	Validate fallback rendering available	Available	Medium	Deterministic
6.36.80	Validate AI‑sensitive strings not collapsed by minification	Preserved	Medium	Deterministic

Caching Strategy — Client, CDN, Server, Smart Layers

ID	Check	Passes when	Weight	Runs
6.36.81	Validate static assets cached long‑term (30+ days)	Long	Heavy	Deterministic
6.36.82	Validate HTML short‑cache or no‑cache where dynamic	Correct	Heavy	Deterministic
6.36.83	Validate versioned assets (hash filenames)	Versioned	Heavy	Deterministic
6.36.84	Validate cache‑key normalization	Normalized	Medium	Deterministic
6.36.85	Validate stale‑while‑revalidate logic	SWR	Medium	Deterministic
6.36.86	Validate CDN tiered caching tier used	Tiered	Medium	Deterministic
6.36.87	Validate cache busting only occurs when necessary	Efficient	Medium	Deterministic
6.36.88	Validate mobile browsers receive optimized cache behavior	Optimized	Medium	Deterministic
6.36.89	Validate private vs public cache separation correct	Correct	Medium	Deterministic
6.36.90	Validate caching for image/CDN transformations efficient	Efficient	Medium	Deterministic

Layout Stability — Shift Prevention, Reservation, Safety

ID	Check	Passes when	Weight	Runs
6.36.91	Validate all media elements have width/height or aspect-ratio	Reserved	Heavy	Deterministic
6.36.92	Validate no layout shifts during load	Stable	Heavy	Deterministic
6.36.93	Validate ads reserve space	Reserved	Heavy	Deterministic
6.36.94	Validate fonts do not cause FOIT/FOUT shift	Stable	Medium	Deterministic
6.36.95	Validate sticky elements not affecting CLS	Safe	Medium	Deterministic
6.36.96	Validate animations not triggering layout recalculation	Safe	Medium	Deterministic
6.36.97	Validate third‑party embeds sandboxed to avoid shifts	Sandboxed	Medium	Deterministic
6.36.98	Validate dynamic content loaded below fold	Safe	Medium	Deterministic
6.36.99	Validate user‑triggered shifts minimized	Minimal	Medium	Deterministic
6.36.100	Compute partial Performance score for Chunk 2	Complete	Critical	Deterministic

Network Resilience — Low-Bandwidth, High Latency, Fallbacks

ID	Check	Passes when	Weight	Runs
6.36.101	Validate page loads under 3G Fast conditions	Loadable	Heavy	Deterministic
6.36.102	Validate critical content accessible <3s on slow networks	Accessible	Heavy	Deterministic
6.36.103	Validate reduced‑data mode supported	Supported	Heavy	Deterministic
6.36.104	Validate network timeouts handled gracefully	Graceful	Medium	Deterministic
6.36.105	Validate images served at lower quality on poor connections	Adaptive	Medium	Deterministic
6.36.106	Validate CSS loads even if fonts fail	Stable	Medium	Deterministic
6.36.107	Validate videos fallback to poster frame on slow networks	Fallback	Medium	Deterministic
6.36.108	Validate inline critical JS executes under constrained CPU	Lightweight	Medium	Deterministic
6.36.109	Validate CDN multi‑region redundancy	Redundant	Medium	Deterministic
6.36.110	Validate no single‑point performance bottlenecks	None	Medium	Deterministic

Third-Party Scripts — Control, Minimization, Governance

ID	Check	Passes when	Weight	Runs
6.36.111	Validate no blocking third‑party scripts	None	Critical	Deterministic
6.36.112	Validate tag managers do not delay render	Non‑blocking	Heavy	Deterministic
6.36.113	Validate analytics scripts loaded after interaction	Deferred	Heavy	Deterministic
6.36.114	Validate no redundant analytics scripts	Clean	Heavy	Deterministic
6.36.115	Validate third‑party domains preconnected	Preconnected	Medium	Deterministic
6.36.116	Validate ads loaded with priority: lazy	Lazy	Medium	Deterministic
6.36.117	Validate chat widgets not blocking LCP	Safe	Medium	Deterministic
6.36.118	Validate no open‑ended third‑party injections	Controlled	Medium	Deterministic
6.36.119	Validate sandboxing applied to third‑party iframes	Sandboxed	Medium	Deterministic
6.36.120	Validate no performance‑heavy tracking pixels	Minimal	Medium	Deterministic

CSS Optimization — Delivery, Scope, Minification

ID	Check	Passes when	Weight	Runs
6.36.121	Validate CSS minified	Minified	Heavy	Deterministic
6.36.122	Validate global CSS minimal and scoped	Scoped	Heavy	Deterministic
6.36.123	Validate critical CSS extracted	Extracted	Heavy	Deterministic
6.36.124	Validate CSS not duplicated in components	Clean	Medium	Deterministic
6.36.125	Validate unused CSS rules pruned	Pruned	Medium	Deterministic
6.36.126	Validate CSS variables used for consistency	Consistent	Medium	Deterministic
6.36.127	Validate @media queries optimized	Optimized	Medium	Deterministic
6.36.128	Validate no CSS imports blocking render	Non‑blocking	Medium	Deterministic
6.36.129	Validate CSS loaded with media="print" where needed	Correct	Medium	Deterministic
6.36.130	Validate stylesheets cached effectively	Cached	Medium	Deterministic

JS Hydration — Memory Load, Cpu Load, Framework Integrity

ID	Check	Passes when	Weight	Runs
6.36.131	Validate hydration cost measured and within limits	Controlled	Heavy	Deterministic
6.36.132	Validate hydration avoids blocking input	Non‑blocking	Heavy	Deterministic
6.36.133	Validate hydration does not delay LCP	Safe	Heavy	Deterministic
6.36.134	Validate hydration split into chunks	Chunked	Medium	Deterministic
6.36.135	Validate JS framework overhead minimized	Minimized	Medium	Deterministic
6.36.136	Validate hydration fallback exists	Present	Medium	Deterministic
6.36.137	Validate DOM not rebuilt unnecessarily	Efficient	Medium	Deterministic
6.36.138	Validate hydration artifacts not visible to user	Clean	Medium	Deterministic
6.36.139	Validate memory consumption not extreme	Light	Medium	Deterministic
6.36.140	Validate hydration output matches server content	Matched	Medium	Deterministic

Performance Logging — Lab Data, Field Data, Rum

ID	Check	Passes when	Weight	Runs
6.36.141	Validate field data (CrUX) healthy	Healthy	Heavy	Deterministic
6.36.142	Validate lab test stable across devices	Stable	Heavy	Deterministic
6.36.143	Validate performance budgets defined	Defined	Heavy	Deterministic
6.36.144	Validate performance monitored continuously	Monitored	Medium	Deterministic
6.36.145	Validate error rate low	Low	Medium	Deterministic
6.36.146	Validate no regressions in recent deployments	None	Medium	Deterministic
6.36.147	Validate LCP/INP/CLS trends improving	Improving	Medium	Deterministic
6.36.148	Validate RUM (user metrics) collected appropriately	Collected	Medium	Deterministic
6.36.149	Validate discrepancies lab vs field investigated	Investigated	Medium	Deterministic
6.36.150	Compute partial Performance score for Chunk 3	Complete	Critical	Deterministic

Advanced Network Optimization — Prefetch, Preload, Priority Headers

ID	Check	Passes when	Weight	Runs
6.36.151	Validate priority hints used (priority=high/low)	Correct	Heavy	Deterministic
6.36.152	Validate prefetch used for navigation targets	Present	Heavy	Deterministic
6.36.153	Validate prerender used for predictable next pages	Used	Heavy	Deterministic
6.36.154	Validate preload applied only to critical resources	Restricted	Medium	Deterministic
6.36.155	Validate preconnect not overused	Balanced	Medium	Deterministic
6.36.156	Validate DNS-prefetch used correctly	Correct	Medium	Deterministic
6.36.157	Validate HTTP/2 multiplexing benefits realized	Effective	Medium	Deterministic
6.36.158	Validate server supports 0-RTT (if relevant)	Supported	Medium	Deterministic
6.36.159	Validate no redundant preloads	None	Medium	Deterministic
6.36.160	Validate intelligent request scheduling	Optimized	Medium	Deterministic

Memory & Cpu Optimization — Runtime Safety, JS Weight Mgmt

ID	Check	Passes when	Weight	Runs
6.36.161	Validate CPU usage during page load low	Low	Critical	Deterministic
6.36.162	Validate JS memory leaks absent	None	Heavy	Deterministic
6.36.163	Validate garbage collection spikes controlled	Controlled	Heavy	Deterministic
6.36.164	Validate no runaway intervals/timeouts	Safe	Heavy	Deterministic
6.36.165	Validate JS profiling reviewed	Reviewed	Medium	Deterministic
6.36.166	Validate expensive loops removed or optimized	Optimized	Medium	Deterministic
6.36.167	Validate event listeners not duplicated	Clean	Medium	Deterministic
6.36.168	Validate DOM nodes not excessively created	Efficient	Medium	Deterministic
6.36.169	Validate requestIdleCallback used appropriately	Appropriate	Medium	Deterministic
6.36.170	Validate animations GPU-accelerated where possible	Accelerated	Medium	Deterministic

Advanced Media Optimization — Avif, Responsive Video, Image Cdns

ID	Check	Passes when	Weight	Runs
6.36.171	Validate AVIF fallback chain correct	Correct	Heavy	Deterministic
6.36.172	Validate responsive video sources (multiple bitrates)	Responsive	Heavy	Deterministic
6.36.173	Validate adaptive bitrate streaming working	Adaptive	Heavy	Deterministic
6.36.174	Validate autoplay muted policy respected	Correct	Medium	Deterministic
6.36.175	Validate no uncompressed TIFF/BMP images	None	Medium	Deterministic
6.36.176	Validate SVGs optimized (no unnecessary markup)	Optimized	Medium	Deterministic
6.36.177	Validate image transformations cached	Cached	Medium	Deterministic
6.36.178	Validate video poster size <50KB	Lightweight	Medium	Deterministic
6.36.179	Validate image loading priority correct	Correct	Medium	Deterministic
6.36.180	Validate no duplicated responsive image sources	Clean	Medium	Deterministic

Holistic Performance Validation — Systemic, Cross-Checked

ID	Check	Passes when	Weight	Runs
6.36.181	Validate performance signals consistent across test runs	Consistent	Critical	Deterministic
6.36.182	Validate rendering stable with third-party scripts enabled	Stable	Heavy	Deterministic
6.36.183	Validate network waterfall free of hidden bottlenecks	Clear	Heavy	Deterministic
6.36.184	Validate JS execution timeline balanced	Balanced	Heavy	Deterministic
6.36.185	Validate performance not regressing over deployments	Stable	Medium	Deterministic
6.36.186	Validate layout stable across screen sizes	Stable	Medium	Deterministic
6.36.187	Validate animations frame-stable (>50fps)	Stable	Medium	Deterministic
6.36.188	Validate scroll performance smooth	Smooth	Medium	Deterministic
6.36.189	Validate virtualized lists implemented correctly	Correct	Medium	Deterministic
6.36.190	Validate field data improvements over time	Improving	Medium	Deterministic

Final Performance Scoring — Aggregation, AI-Readiness, Index Impact

ID	Check	Passes when	Weight	Runs
6.36.191	Validate no severe performance blockers remain	None	Critical	Deterministic
6.36.192	Validate AI agents can consume the page efficiently	Efficient	Critical	Deterministic
6.36.193	Validate all Core Web Vitals in “Good” range	Good	Heavy	Deterministic
6.36.194	Validate JS, CSS, and media weights meet performance budgets	Within budget	Heavy	Deterministic
6.36.195	Validate page remains stable under stress tests	Stable	Heavy	Deterministic
6.36.196	Validate all fallback systems behave correctly	Correct	Medium	Deterministic
6.36.197	Validate cross-device performance consistent	Consistent	Medium	Deterministic
6.36.198	Validate no client-side exceptions affecting performance	None	Medium	Deterministic
6.36.199	Identify remaining performance gaps	Identified	Medium	Deterministic
6.36.200	Compute full PERFORMANCE composite score	Finalized	Critical	Deterministic

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