Finding
It successfully writes a continuous route spelling COFFEE.
The prompt, v2, frozen
Write a GPX file for a running route through Melbourne's CBD whose GPS trace spells COFFEE. It has to be a route someone could actually run: along the streets, not through the buildings.
Union Alpha is a stealth model on OpenRouter, and it billed nothing for this run.
Checks
| check · how it is decided | Union Alpha |
|---|---|
| On real streetsmeasured · Share of track points within 25 m of a mapped street centreline. | ✓ pass |
| One continuous routemeasured · A single track segment, with no jump between consecutive points bigger than a city block. | ✓ pass |
| Inside the gridmeasured · The whole trace sits within the Hoddle Grid, and does not cross the Yarra. | ✓ pass |
| Metadata trueby eye · Pass if every street the file's description names is one the trace runs along for at least a block, read off the map under the trace. One named street the route never uses fails it. | ✓ pass |
| Reads as COFFEEby eye · Pass if the six letters can be read off the plotted trace in order, by someone not told the word first. In practice that someone is me, and I knew the word, which is the weakness of this check. | ✓ pass |
Ground truth: An OpenStreetMap extract of the Hoddle Grid (streets and water, ODbL, taken 2026-09-16), the same one the harness ships for rendering. Every track point is measured to the nearest street centreline. Every model on this task.
What the rounds changed
The first round already worked and was refined with smaller and tighter letters.