# Sound Transit

**Canonical:** https://apis.io/providers/sound-transit/  
**Website:** https://www.soundtransit.org/  
**APIs profiled:** 7

Sound Transit is a regional transit authority serving the Seattle-Puget Sound area of Washington State, operating light rail, commuter rail, and express bus services. The Sound Transit Open Transit Data (OTD) program provides GTFS static and real-time data feeds, OneBusAway API access, and GTFS-RT service alerts for transit application developers and researchers.

## Kin Score — 34.2 / 100 (thin)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 34.2).

| Facet | Score |
|---|---|
| Discoverability | 74.1 |
| Contract Quality | 58.9 |
| Governance | 9.8 |
| Contract Governance | 9.8 |
| Operational Transparency | 10.5 |
| Developer Ergonomics | 14.3 |
| Commercial Clarity | 28.6 |
| Access Clarity | 28.6 |

Regulatory layer — **Government & Public Sector**: 27.8 (matched via tags).

## Agent readiness — 24.5 (agent-aware)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | na |
| MCP Server | no |
| Auth Clarity | no |
| Idempotency | na |
| Error Semantics | no |
| OpenAPI Examples | no |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | na |

## Access

Freemium — onboarding: unknown, pricing: freemium, trial: no (confidence: medium).

## APIs (7)

- **Sound Transit Agencies API** — Transit agency information and coverage
- **Sound Transit Arrivals And Departures API** — Real-time and scheduled arrival/departure information
- **Sound Transit Routes API** — Route definitions and schedules
- **Sound Transit Stops API** — Stop locations and schedules
- **Sound Transit System API** — System utilities and configuration
- **Sound Transit Trips API** — Trip details and active vehicle positions
- **Sound Transit Vehicles API** — Active vehicle locations and assignments

## Agentic access (1)

- **Sound Transit Agentic Access** — 20 operations

## Security (1)

- **Sound Transit Domain Security** — TLSv1.3 · HSTS · DMARC

## Plans (1)

- **Sound Transit Plans Pricing**

## Tags

Transit, Transportation, GTFS, Real-Time, Public Transit, Government, Seattle

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/sound-transit/). Scores are computed from the provider's own public artifacts under a published rubric.