Honest, assertion-rich unit suite at the weather-service seam: the new tests assert exact spec values (nyc forecast rows [1,27,humid]/[2,24,rain]/[3,22,cloudy] via deepStrictEqual; rome day 2 = 26/'cloudy' — the task's pinned scenario), cover all four cities' switching at the service level, and add unknown-city error paths for both card and forecast. No skipped or hard-coded tests; expected values match the pinned dataset and conversion math. But the task's actual subject — the interactive flows (city-nav switching, forecast open/back, return-to-card) — is app.js state-machine logic with zero automated coverage at any level; the previously flagged missing DOM/render test was not addressed, and the untested surface grew this session. No screencast/video exists in .ololo/artifacts (stills only), so the assembled product's flows rest on manual verification, which the task contract says cannot prove them. Proportionate unit strength on the wrong seam for this task's core risk: capped below the integration-less ceiling, not near it.

The surfaces I can see are genuinely designed: the card captures show a crisp hierarchy (city h1, emoji icon, dominant temperature, capitalized condition, wind line), consistent pill controls with a yellow active state, a prominent 'View 3-day forecast' CTA (bangkok-f-desktop.png), and polite empty/error states (empty-desktop.png, atlantis-desktop.png). But the task's headline surface — the 3-day forecast view — has no delivered capture at all, so its actual rendering (the 3-column day grid, cell density, 'thunderstorm' wrapping) could not be visually reviewed; that gap caps confidence. Minor: the new captures show the widget top-aligned rather than the earlier vertically-centered placement.

Markup is solid: lang="en" (index.html:2), semantic

No true narrow-viewport capture was delivered this session (rome-mobile.png exists in the repo but was not among the attached artifacts, and the prior session's mobile shot was a cropped 500px render — that concern is not visibly resolved). CSS evidence of responsiveness is good: the widget is max-width 360px so the desktop captures nearly show the narrow rendering, the city nav wraps (style.css:104), and a @media (max-width: 420px) query collapses the forecast grid to one column (style.css:179). Pills are touch-sized but on the small side (0.4rem vertical padding). Narrow rendering of the forecast remains unverified, so the score stays conservative.

Beyond the letter of the brief, the increment adds a handful of genuine, code-provable user-facing touches: the forecast view keeps the °C/°F toggle so all three days convert with the user's chosen units (app.js:75, weather-service.js getForecastViewModel), and keeps the city nav so a visitor can jump between cities' forecasts without first returning to a card (app.js:77) — brief only required a back button (app.js:76). Each forecast day also gets its condition icon (app.js:64) with the rain emoji added to the map (data/weather-data.js), the forecast grid collapses to one column under 420px (style.css @media block), every interactive control gained hover feedback (style.css hover rules), and in-app navigation uses semantic s instead of reload-inducing links. Entry point visually confirmed on the running widget in the delivered bangkok-f-desktop.png; dataset fidelity (rome day 2 = 26/cloudy) is test-asserted in test.js and committed in data/forecast-data.js. Carried-over task-#0 strengths (empty state, quick-picks, forgiving input, units toggle on the card) are deliberately not re-credited. No memorable signature feature, and the required .ololo/weather-widget-forecast-done.md is still missing with no screencast delivered, so the interactive flows are evidenced by code+tests+stills rather than the demanded video — hence solidly above baseline but short of the memorable tier.

Naming is clear throughout (getForecastViewModel, renderForecast, data-action attributes) and data/forecast-data.js is pure, well-headed static data matching the pinned table. Deductions: dead CSS kept while those lines were edited this session (style.css:83 keeps .units-toggle a and :95 keeps .units-toggle a.active after links became buttons; style.css:11 adds an html { box-sizing } rule that duplicates the * rule); the day view-models carry tempC/temp no renderer reads (weather-service.js:83-84), the same dead-field pattern faulted in task 1 now propagated into new code; the state comment at app.js:14 lists an "unknown" view value that is never assigned (unknown is derived from !vm.found in render); and the units-normalization expression is pasted a third time into app.js:144 on top of weather-service.js:48 and :78. No duplication report exists in the evidence, but by inspection duplicated fragments are 1-3 lines — well under 10%, so no cap applies.

A newcomer can extend this safely: adding a city means one entry per data file — city nav, forecast, and tests derive automatically via listCities/getForecastViewModel. Functions are short (longest, render(), ~27 lines), nesting stays at depth 2, event delegation via data-action is idiomatic and extensible, and boundaries are handled (unknown-city fallback on both card and forecast paths at app.js:100/109, icon fallback || "🌡️"). Deductions: render() mutates global state (state.cityId = vm.cityId, app.js:113) — a side effect a reader won't expect in a function named render; units normalization lives in three unshared copies, so a units change touches two files; AGENTS.md still describes the old link-based navigation ('city nav links, units toggle links'), omits the forecast layer and data/forecast-data.js, and the repo at the task commit still lacks the required .ololo/weather-widget-forecast-done.md. The unescaped query interpolated into innerHTML at app.js:84 is the defect already charged in my task-1 review and is noted, not re-charged.

The task-0 layering was extended cleanly rather than fused. The new forecast is a third pure-data file (data/forecast-data.js:1-37, 'No formatting, no logic'), a new view-model method in the DOM-free service (weather-service.js:67-94 getForecastViewModel, mirroring getCardViewModel's found/not-found contract), and presentation-only render functions in app.js. app.js now holds a small explicit UI state machine ({cityId, view, units}) with one render() dispatcher, one delegated click handler (handleClick), and one template function per view (cityNav, unitsToggle, renderCard, renderForecast, renderUnknown, renderEmpty) — each small and single-purpose, so switching, forecast-open and back are all plain state transitions with no logic buried in markup. Dependency direction stays one-way (index.html script order data → service → app; app.js knows WeatherService, never the datasets), and the dual browser/Node export pattern keeps the service unit-testable outside the DOM — test.js:51-81 now covers every-city card landing, 3-day forecast shape, the rome day-2 26/cloudy case, and unknown-city forecast. Proportionality is right: in-memory state plus re-render is the minimal structure that satisfies 'without touching the address bar', with no framework, router, or needless abstraction. Deductions are minor: AGENTS.md has drifted — it still describes app.js as rendering 'city nav links, units toggle links' (now data-action buttons) and never mentions forecast-data.js, getForecastViewModel, or the state machine, so the repo-level doc lags the code even though the per-file header comments are accurate; the state comment lists a 'unknown' view value that is never assigned (unknown is derived from vm.found in render, app.js:120-135); and render() mutates state.cityId = vm.cityId as a side effect inside presentation (app.js:132). Relative to my task-0 verdict: the separation I praised is intact and consistently extended; the earlier trivial nits are gone but AGENTS.md, previously accurate, is now the stale piece.

All three scenarios are implemented and code-verified: city-nav on every view reaches every other city in one click without touching the URL (app.js cityNav/handleClick), the card's forecast button opens a 3-day view with a working back path, and data/forecast-data.js matches the pinned table exactly (rome day 2 = 26/'cloudy'), backed by new tests in test.js. The prior rendering failure I faulted is fixed — stills show live Rome/Bangkok cards with the forecast button. But the contract's verification mode for the two living flows produced nothing: no screencast exists (my probe request failed — session already over), no artifact shows the forecast view at all, and the required .ololo/weather-widget-forecast-done.md was never written (the only note is the stale task-#0 one).

The pinned forecast dataset exists in exactly one place (data/forecast-data.js) and matches the brief value-for-value: nyc 27/24/22 humid-rain-cloudy, sao-paulo 18/21/20 rain-sunny-cloudy, bangkok 34/32/33 thunderstorm-rain-humid, rome 30/26/27 sunny-cloudy-sunny. It is kept as a separate file from the task-#0 card dataset (data/weather-data.js) rather than as a drifting copy, with no redeclaration anywhere. app.js contains zero baked-in weather values — even the city switcher nav is generated from WeatherService.listCities() over the dataset, and day numbering comes from array index. Access to the forecast is funneled through one interface (getForecastViewModel, weather-service.js:73-101), keyed off the same normalized city id as the card, with the shared CONDITION_ICONS map from the single data module. No shadow data: test.js holds expected values only as a test suite, index.html and style.css carry no data. Sourcing is honest — nothing displayed is fabricated beyond the pinned tables. The scenario value (rome day 2 = 26 cloudy) is asserted in test.js:74-80. The residual half-point is the same soft spot I faulted in task #0 and the player has not fixed: tempDisplay/windDisplay display-string composition still lives in the service layer rather than the UI; not charging it twice beyond the light hold, and AGENTS.md still describes the old query-param navigation instead of the new in-memory state + forecast data layer (doc drift, not a data defect).

Final captures (probe:8405fb64-c66c-4a2c-a656-411a62011c2d) show a deliberate visual system: glass card on a blue-violet gradient, hierarchy city → icon → 3rem temperature → condition → wind, consistent pill components, yellow accent for active unit/city. The 91°F and 29°C states are legible at a glance and the unknown-city state (atlantis-desktop.png) pairs a clear salmon error message with the city nav as recovery. Minor deductions: the pill rows stack into three separate rows making the card slightly busy, and the visible 'View 3-day forecast' control has no wired behavior in the committed code. The early empty-card capture (probe:d0dff08d-ed56-4877-b551-11ab3a4f44cc, rome.png) is superseded by all later renders of the same URL.

Markup (commit:b3c844ce) has lang="en" (index.html:3), a semantic

A narrow artifact was delivered (rome-mobile.png, probe:8405fb64-c66c-4a2c-a656-411a62011c2d) and shows the card rendering cleanly — large legible temperature, wrapped city nav, touch-sized pill targets, no overlap. However the capture is cropped at the right edge ('Bangko' sliced mid-glyph), and the geometry (card left edge ~70px) matches a ~500px-wide render cropped to 375 rather than overflow at 375px — a centered flex item overflowing 375px would clip both sides, and the committed CSS (viewport meta index.html:6, width:100% + max-width:360px style.css:27-33, flex-wrap nav) cannot overflow at 375. The page most likely holds up at true mobile width, but the delivered capture does not cleanly demonstrate it, so it cannot earn full marks.

The widget is broken in its actual medium: all four participant-delivered browser screenshots (rome, atlantis, bangkok-f, plus the probe d0dff08d rome.png) show an empty, textless card — no temperature, no condition, no 'unknown city' message. Root cause in code: data/weather-data.js:11 declares the dataset with a top-level const, which never becomes a window property, while weather-service.js:15 (browser branch) reads it as root.WEATHER_DATA → undefined. Every render path then throws: getCardViewModel hits WEATHER_DATA[cityId] on undefined (weather-service.js:35) and even the empty/unknown states die in listCities() via Object.keys(undefined) (weather-service.js:24, called from app.js cityNav). All three required scenarios (rome 29/sunny, bangkok 91°F, atlantis 'unknown city') therefore fail in the browser. The 5 passing tests (test.js) only cover the CommonJS require() path, which the page never exercises — a false signal of health. Credit for a clean data/service/presentation layering, correct service logic, complete AGENTS.md with run:/test: lines, and an honest done note; but the product the visitor opens shows nothing, so the score stays near the floor.

Single source of truth: the four-city dataset lives only in data/weather-data.js (WEATHER_DATA, lines 12-17) and matches the brief exactly (nyc 26/humid/15, sao-paulo 19/cloudy/11, bangkok 33/thunderstorm/8, rome 29/sunny/12); CONDITION_ICONS there is UI metadata, not a data copy. No shadow data: index.html is an empty shell, style.css is pure styling, app.js generates city links via WeatherService.listCities() rather than hardcoding values, and test.js pins expected numbers (29, 91) only as test assertions — no mock or leftover sample data ships, and AGENTS.md states no network calls, so nothing was fetched or fabricated. Data layer separation is clean and documented: a pure data module ('No logic, no formatting'), a DOM-free service/view-model layer (normalization, C*9/5+32 rounded, unknown-city case), and a presentation layer that only reads query params and renders; dual browser-global/CommonJS exports make the data unit-testable. Minor deductions: 'Sao Paulo' label drops the tilde (cosmetic, presentation metadata), and tempDisplay/windDisplay strings are composed in the service (weather-service.js:44-46) slightly blurring the view-model/formatting boundary — deliberate and documented, but a purist view would put that in the UI layer.

The analysis states no numeric score for this criterion. It catalogs beyond-the-brief features all 'provable in committed code and coherent': an empty state with quick-pick nav for the brief-never-defined no-param case, city quick-pick navigation with active highlighting, forgiving city input normalized for case/whitespace (test-covered), a units toggle that preserves the city, a condition-to-emoji icon map with fallback, an error message echoing the bad query, and the brief-invited wind display. It concludes the work is 'a cohesive set of five-plus genuine, working usability touches — well above the plain baseline, not yet the "demo audience remembers it" tier,' while noting nothing rises to a single memorable signature feature.

Clear layering (data / service / presentation) with precise naming (normalizeCityId, celsiusToFahrenheit, getCardViewModel) and purposeful comments. Duplication is minimal (~500 lines total; only the justified dual-env export boilerplate repeated twice and near-identical CSS pill styles). Small dead spots: unused other variable and an unused tempC field on the view-model keep it from scoring higher.

Short functions (longest ~25 lines), shallow nesting, named constants, and a DOM-free service layer that the test suite (test.js:8-31) exercises for all three scenarios plus formula/normalization — a newcomer can navigate and extend this safely. Main hazard: renderUnknown injects the raw ?city= query into innerHTML unescaped (app.js:51), an XSS at the single boundary where untrusted input meets the DOM; the UMD-lite IIFE in weather-service.js is mild cleverness but well-commented. AGENTS.md carries the required run:/test: lines (AGENTS.md:33-34).

Five honest, assertion-backed tests in test.js covering all three required scenarios at the service layer: Rome 29/sunny (test.js:13-18), Bangkok Fahrenheit 91 including the rounding path (test.js:20-24), unknown city 'unknown city' (test.js:26-30), plus the conversion formula against all four dataset temps (test.js:32-37) and city-id normalization (test.js:39-41). Expectations are concrete spec values, not implementation restatements, and the dependency-free runner fails properly (thrown assert → non-zero exit). Deductions: no test exercises the assembled product — app.js readParams() and DOM rendering, and the actual ?city=/&units= URL flow the scenarios describe, are verified only manually; a regression in the presentation layer would pass the suite. Minor gaps: empty city and invalid units value untested. Proportionate to task size, but unit-only coverage of a browser-facing scenario set caps at 7.0.