Method
How a street becomes a score.
The same open rubric, the same bins, and a hard line between what a camera proposed and what a field audit verified.
The honesty contract
StreetLens publishes two kinds of evidence. Confusing them would make the numbers look stronger than they are.
- Camera-observed: a vision model proposes scores; an admin reviews the walk before anything is public. Provisional until field-audited.
- Field-audited: a person scores the street against rubric v0.1 on site. This is the source of truth for Ley 7600 compliance claims.
- Counters and means never mix the two. Insights, the map, and the landing keep them labeled apart.
Lineage
The rubric derives from validated instruments, not invented ones.
MAPS-Mini
A validated microscale audit of pedestrian streetscapes: sidewalks, crossings, and buffers.
LANAMME-UCR
Costa Rica's national road-materials laboratory at the University of Costa Rica, for pavement and condition standards.
Ley 7600
Equal Opportunities for Persons with Disabilities Act and its Reglamento (Decreto Ejecutivo N° 26831-MP).
OpenStreetMap
Segment geometry under ODbL; audited sidewalk geometry is contributed back under OpenSidewalks.
The five lenses
Every segment is scored 0–100 on four independent lenses plus an overall composite. The same instrument runs in any municipality — Escazú is the pilot, not a special case in the math.
Accessibility
Curb ramps, tactile paving, safe crossings, effective width — can everyone use this sidewalk?
Drainage
Grates and inlets, cross slope, ponding history — does it flood, or drain?
Shade
Tree canopy, cover, sun exposure — heat resilience on the sidewalk.
Bike
Lanes, separation from traffic, connectivity — can you ride it, and is it protected?
Overall
The composite sidewalk score — one number anyone can act on.
Accessibility and the law
An accessibility score below 50 is treated as failing the legal minimum for audited segments. Camera scores use the same scale for orientation only — they are not legal determinations.
- Art. 125 — sidewalks ≥ 1.20 m, non-slip, no steps, cross slope ≤ 3%.
- Art. 126 — curb ramps at corners, gradient ≤ 10%, width ≥ 1.20 m.
- Art. 127 — signs and projecting objects clear ≥ 2.20 m.
Scoring bins
Scores are continuous 0–100 and grouped into four legend bins. The legend is never color-only.
| Bin | Range |
|---|---|
| Excellent | 80–100 |
| Good | 60–79 |
| Fair | 40–59 |
| Poor | 0–39 |
Re-audits are first-class
When a street is walked again, the newest walk becomes the canonical camera reading and earlier ones move to archive. Change over time — did it get fixed? — is queryable once multiple observations exist.