Manifest position 355 · CrUX rank bucket 1000

https://www.gov.uk

Coverage complete

Coverage-complete atomic audit of six representative GOV.UK templates, one transactional step, and a 404 recovery state. Excluded: external sign-in destinations, authenticated account areas, payment/checkout, individual country pages, and every sitemap URL because they are separate hosts/flows or duplicate the selected archetypes.

Attempts

1 / 3

Judged checks

58 / 58

Blocked

Not run

This report has no published overall score. Blocked and not-run checks are not passes. A coverage-complete report means every check has a judged outcome; it does not mean every check passed.

All 58 atomic check outcomes

Principle / check	Status	Confidence	Evidence or reason
respect-user-preferences `respects-color-scheme`	issues	high	Screenshot and CSS probe under prefers-color-scheme: dark showed no palette adaptation. F-001 medium: GOV.UK does not adapt its palette to the user’s dark colour-scheme preference.
respect-user-preferences `respects-reduced-motion`	pass	high	The reduced-motion emulation was active, no running animations were exposed, and the stylesheet includes reduced-motion handling.
respect-user-preferences `respects-contrast`	pass	high	Forced/high-contrast CSS rules are present and the prefers-contrast screenshot retained visible text and controls.
implement-natural-interactions `view-transitions`	issues	medium	Representative same-origin route changes were abrupt and multiple templates had no View Transition declaration. F-002 low: Cross-document navigation still swaps pages abruptly rather than using progressively enhanced View Transitions.
implement-natural-interactions `scroll-driven-animations`	pass	high	No scroll-linked visual effect or scroll event animation was observed on the representative templates; the UI does not implement a main-thread parallax anti-pattern.
implement-natural-interactions `physical-gestures`	pass	high	Navigation and disclosure interactions use native links, buttons, details, and standard scrolling; no custom pointermove gesture layer was observed.
provide-guided-navigation `scroll-state-aware-chrome`	pass	high	The audited pages avoid persistent sticky chrome that needs scroll-state adaptation; contents, step, and A-Z navigation remain available in document flow.
provide-guided-navigation `anchored-positioning`	pass	high	No tooltip or floating menu that could drift from an anchor was present on the audited paths; menus are in-flow and edge-safe.
provide-guided-navigation `directs-attention`	pass	high	Breadcrumbs, contents links, step navigation, descriptive headings, and visible focus cues consistently orient users.
maximize-content-reduce-noise `no-intrusive-interruptions`	pass	high	The cookie choice is an in-flow banner that pushes rather than obscures content, offers accept/reject/settings equally, and no modal interstitial appeared.
maximize-content-reduce-noise `semantic-dismissible-primitives`	pass	high	Audited controls use native buttons, fieldsets, radios, selects, and details; no ad-hoc modal div was found.
maximize-content-reduce-noise `reduced-chrome`	pass	high	Screenshots show a restrained design with content-dominant layouts, limited framing, and consistent navigation/footer chrome.
adapt-to-the-form-factor `responsive-no-horizontal-scroll`	pass	high	All six representative templates reported 0px horizontal overflow at 360x800 and included a viewport meta tag.
adapt-to-the-form-factor `component-level-responsiveness`	pass	high	Container-query and logical-property signals are present in major shared templates, and mobile screenshots show components reflowing rather than merely shrinking.
adapt-to-the-form-factor `input-modality-aware`	pass	high	Lighthouse accessibility scored 1.0; controls retained strong focus styling and the mobile layouts kept controls usable.
support-core-task-success `clear-purpose-and-primary-action`	pass	high	Each archetype exposes a descriptive H1 and an obvious next action: search, topic links, contents, country lookup, or Start now.
support-core-task-success `primary-flow-completion`	pass	high	A passport query returned 5,962 filterable results and the State Pension journey advanced from its landing page to a clearly labelled first question without an account wall.
support-core-task-success `clear-system-state-and-recovery`	pass	high	The search reports its result count and a deliberately invalid route returns a titled 404 with homepage and search recovery routes.
be-fast-and-stable `good-core-web-vitals`	issues	high	Lighthouse measured LCP 1.6s and TBT 0ms but CLS 0.565, above the good threshold. F-003 high: The lab Core Web Vitals run fails the good CLS threshold despite fast paint and an idle main thread.
be-fast-and-stable `visual-stability`	issues	high	Lighthouse reported CLS 0.565; the separate mobile observer also recorded a late shift at 2.37s, though only 0.0129. F-004 high: The homepage has a substantial condition-dependent layout shift during the Lighthouse load.
be-fast-and-stable `efficient-main-thread`	pass	high	The trace and Lighthouse both recorded zero long tasks/zero total blocking time.
be-fast-and-stable `efficient-resource-delivery`	pass	high	The load transferred 205,446 bytes in 17 successful requests with no cache, compression, redirect, or HTTP hygiene warnings; the flagged application script is type=module at the body end and therefore deferred by platform semantics.
be-fast-and-stable `trim-unused-and-duplicate-code`	issues	high	Lighthouse estimated 26,909 bytes unused JS and 39,277 bytes unused CSS on the homepage. F-005 low: The homepage ships a mostly unused shared CSS bundle and a substantially unused JavaScript bundle.
be-inclusive `names-roles-labels`	pass	high	Lighthouse accessibility scored 1.0 with image-alt, form-label, and link-name audits passing; DOM probes found labels on representative fields.
be-inclusive `sufficient-contrast`	pass	high	Lighthouse colour contrast passed and the high-contrast screenshot preserved legible controls and text.
be-inclusive `structure-and-focus`	pass	high	Lighthouse heading order passed; landmarks and headings were present on all templates, with skip navigation and visible high-contrast focus styling.
be-inclusive `legible-text`	pass	high	Representative desktop and 360px screenshots show generous line spacing, readable measure, clear hierarchy, and no clipping or overflow.
be-inclusive `zoom-reflow-targets-and-media`	pass	high	All templates reflowed at 360px without horizontal overflow, viewport scaling was not disabled, and Lighthouse accessibility scored 1.0. No audited path contained time-based media requiring captions.
follow-best-practices `no-console-errors`	pass	high	Lighthouse found no browser errors logged to the console.
follow-best-practices `sound-document-and-assets`	pass	high	Lighthouse doctype and charset audits passed; all homepage images had explicit dimensions and correct display proportions.
follow-best-practices `browser-platform-hygiene`	pass	high	Lighthouse best-practices scored 1.0 and reported no BFCache blocker; no permission prompt or paste prevention appeared during the paths.
be-discoverable `title-and-description`	pass	high	Every representative template had a descriptive title and meta description.
be-discoverable `crawlable-and-mobile-friendly`	pass	high	Lighthouse SEO scored 1.0; links, viewport, and robots audits passed, while raw HTML retained all rendered content words.
be-discoverable `canonical-and-indexing-signals`	pass	high	Public pages returned 200 and robots.txt points to a current sitemap; canonical URLs were present on homepage, article, calculator, and intentionally noindexed search canonicalized to the search endpoint.
be-discoverable `structured-and-shareable-metadata`	pass	high	Entity-bearing article and service templates exposed JSON-LD and Open Graph metadata; the homepage also exposed social metadata.
be-private-and-secure `secure-transport-and-headers`	pass	high	HTTPS, nonce-based CSP, HSTS, nosniff, frame protection, Referrer-Policy, and Permissions-Policy were present. The sole first-party preference cookie was Secure and not authentication-sensitive.
be-private-and-secure `data-minimisation-and-third-parties`	pass	high	Before optional consent, the network and tracker probes observed zero third-party requests/origins and no known trackers.
be-private-and-secure `in-context-permissions-and-modern-auth`	pass	high	No browser permission request occurred on load and no authentication form was present in the audited GOV.UK templates; sign-in destinations were links to separate services, so passkey support was not asserted here.
be-private-and-secure `defensive-browser-policies`	pass	high	HSTS, SAMEORIGIN/frame-ancestors, a nonce CSP, strict-origin referrer policy, and a permissions policy were all active; no third-party cookie was set.
be-resilient `progressive-enhancement`	pass	high	Raw-server HTML contained 100% of rendered content words on homepage, article, and search, with titles/descriptions preserved and no empty app shell.
be-resilient `resilient-runtime-behaviour`	pass	high	Native, in-flow controls avoided clipped overlays; the menu toggled aria-expanded predictably and no console/runtime error was reported.
be-resilient `offline-and-installable`	not-applicable	high	The audited property is a public, server-rendered information and service directory rather than an installable web app; offline completion of live government transactions was not treated as a requirement.
be-resilient `network-and-http-failure-states`	pass	high	A deliberate unknown route returned a clear Page not found state, status code 404, and actionable homepage/search recovery.
be-internationalised `lang-dir-and-logical-properties`	pass	high	All representative documents declared lang=en and shared CSS included logical inline/block properties; content and reading order were coherent.
be-internationalised `locale-aware-data`	not-applicable	high	The representative public paths are deliberately UK-English and did not present currency, user-locale number formatting, or locale-selectable data requiring an Intl comparison.
be-internationalised `time-zone-correctness`	not-applicable	high	No audited path displayed or accepted time-zone-sensitive events or timestamps; a time-zone/DST implementation claim would be fabricated.
be-trustworthy `no-dark-patterns`	pass	high	Cookie accept and reject actions have equal prominence, settings are linked, and no disguised advertising, forced continuity, or confirmshaming appeared.
be-trustworthy `humane-error-handling`	pass	high	The calculator uses a clear fieldset/radio question and preserves browser/server navigation; the exercised 404 uses plain language and recovery actions rather than blame.
be-trustworthy `trustworthy-input-assistance`	pass	high	Search and filter inputs had explicit labels and appropriate input types; autocomplete=off was limited to searches and a bot-trap, not personal identity/payment fields.
be-trustworthy `safe-commercial-and-account-flows`	not-applicable	high	No checkout, subscription, authentication, consent grant beyond optional cookies, or account-management form was part of the representative GOV.UK-owned paths; outbound sign-in services were not audited as this host.
be-sustainable `optimised-assets`	issues	high	The image audit found four legacy PNG promotional images and one 240px app icon rendered at 80px, although all were dimensioned and lazy-loaded. F-006 low: Homepage promotional raster assets are all legacy PNGs, and the app icon is delivered at three times its rendered width.
be-sustainable `no-wasteful-work`	pass	high	The page loaded only 17 requests, transferred 205KB, had no third-party requests, and trace observers saw no long tasks or persistent animation.
be-sustainable `third-party-and-media-budget`	pass	high	The homepage transferred 205KB with zero third-party bytes, no audio/video, no autoplay, and only 25KB of images.
be-agent-ready `structured-agent-capabilities`	not-applicable	high	This is an information and navigation publication with crawlable semantic HTML, not a declared agent-action surface; no WebMCP capability requirement was inferred.
be-agent-ready `on-device-inference`	not-applicable	high	No summarisation or language-model feature is offered on the audited pages, so requiring on-device inference would add a feature unrelated to the site’s stated tasks.
be-memory-efficient `no-leak-under-repeated-interaction`	pass	high	After ten menu open/close cycles, heap grew only 69,109 bytes (1.14%) and 800 nodes (0.71%); constructor populations remained essentially stable.
be-memory-efficient `bounded-footprint`	pass	high	The homepage heap was about 6.04MB with 112,444 snapshot nodes, proportionate for the 129-control server-rendered page.
be-memory-efficient `no-detached-dom-or-unbounded-listeners`	pass	high	No Detached constructor appeared among the top constructors, and repeated menu interaction added only 7 closures and 2 arrays, with no material accumulation signal.

Provenance

Canonical report: results/atomic/reports/0355-www_gov_uk.json
Report SHA-256: 9667dc8c4d7f19e170d8b6a596b94cded5073660e8ca83eff114fb7808f5b22d
Local retained report: runs/2026-07-17T17-27-24-856Z/atomic-reports/www_gov_uk/2026-07-20T04-40-09-666Z/report.json
Local evidence root: runs/2026-07-17T17-27-24-856Z/atomic-reports/www_gov_uk/2026-07-20T04-40-09-666Z
Catalog SHA-256: sha256:78ccfdb2d483f4c57d9dafed80fd86c6265585a56457c8dcfddc254b80fb44d7

Raw screenshots, HARs, traces, heaps, and other browser artifacts are retained at the local evidence root and intentionally are not committed. Artifact paths in the canonical report are relative to that root.