# Validation — Concourse Divide / Kimi K3.1 Pro

Superbench 2.1 brief 22. Fresh tool-free generation with a compact-output limit; the published `index.html` is the agent's complete closing document, without an operator repair.

## Artifact and environment

| Item | Value |
| --- | --- |
| Artifact | `index.html`, 17,572 bytes, one inline script, closing `</html>` present |
| Standalone checks | Pass: JavaScript parsed with `new Function`; no external script, stylesheet, image, fetch, XHR, or WebSocket dependency found |
| Browser | Google Chrome 155.0.8059.84, headless CDP, Node v22.23.3 |
| Loads | `file://`, offline network emulation, 1280×720 and 390×844 |
| Smoke result | No runtime exceptions, console errors, or external requests; body width matched both viewports |

## Targeted reviewer checks

These are post-delivery operator checks, not authoring-agent claims or a complete rubric adjudication. One recovery sequence used the normal real-time animation loop. A separate cross-check accelerated time by invoking the artifact's own `step(1/60)` in one-second chunks with animation frames paused; traveler positions, destinations, IDs, and gate states were not directly assigned in either sequence.

| Check | Result | Evidence |
| --- | --- | --- |
| Two seeded flows and conservation | Pass | 24 cyan + 24 amber travelers; active + arrived remained 48 |
| Pause and resume | Pass | Simulation time stayed fixed while paused, then advanced after resume |
| Reset determinism | Pass | Two reset/pause cycles produced identical IDs, positions, and destination slots at simulation time 0 |
| Traveler selection and trail | Pass | Real pointer input selected C01; detail showed its North route and 16 actual trail samples at capture |
| Gate control | Pass | North button entered `closing`; the artifact's drain/seal path remained active |
| Open-gate movement and arrivals | Pass | After a separate 14-second open-gate run, 46 had arrived and 2 remained active; total remained 48 |
| All-closed, South-only recovery | **Fail** | Under the normal real-time animation loop, Center drained and closed after the 3-second mark and all gates closed by simulation second 10.73. Reopening only South restored movement, but 90 recovery seconds ended with 47 arrived and 1 waiting; it remained stuck at 95.17 seconds. Requirement: all 48 within 90 seconds |
| Accelerated recovery cross-check | **Fail** | A separate fixed-step run closed all gates by simulation second 10 and reached a state where only 43 had arrived and 5 remained active after 90 recovery seconds. This confirms failure in both drivers, with different stall counts |
| Supplemental collision audit | **Not clean** | During the accelerated recovery run, minimum pair-center distance was 13.959 versus body diameter 14; four wall-overlap samples were counted. Shutter-overlap count was 0 and active + arrived remained 48 |
| Render nonblank | Pass | Sampled canvas pixels contained 164 distinct RGBA colors |
| Runtime during interactions | Pass | No uncaught exceptions during the targeted checklist |

## Limits and unchecked items

- No numeric score or full rubric passage is claimed. Screenshots were captured but not visually reviewed; pixel diversity is not an aesthetic judgment.
- The required South-only all-48 recovery was exercised and failed; it must not be described as passing. Other gate-first permutations, exhaustive head-on deadlock cases, every keyboard shortcut, and extended repeat/soak testing beyond the two failed recoveries remain unreviewed.
- Mobile layout had no horizontal overflow; its document scrolls vertically to the controls. Not every touch gesture was exercised.