# WenToGo developers

> The developer-facing half of WenToGo in one place: one read-only JSON endpoint, no authentication, structured errors and an edge rate limit. Scoped companion to the site-wide [llms.txt](https://wentogo.com/llms.txt).

## The endpoint

- [OpenAPI 3.1 specification](https://wentogo.com/openapi.json): `GET /api/trip/{country}/{destination}/{start}/{end}` — the score and factor breakdown for exact dates. Its HTML equivalent at `/trip/{country}/{destination}/{start}/{end}` also shows better nearby windows. Every operation is a read-only GET, so retries are always safe.
- [Developer portal](https://wentogo.com/developers/): the human-readable quickstart with a curl example, the error model and the limits.

## Conventions

- No authentication anywhere: no key, no token, no Authorization header. The written statement is [auth.md](https://wentogo.com/auth.md).
- Every `/api/` path returns JSON, including errors: `{source_version, error: {code, message}}` with a stable code. An unknown `/api/` path answers 404 with `NOT_PART_OF_PUBLIC_API`.
- Fair use: 20 requests per 10 seconds per client IP across all `/api/` paths, then a 429 from the edge. On a 429, wait ten seconds and retry. Prerendered pages are not limited.
- Cache by request URL plus `source_version`: identical inputs under the same version return identical answers.

## Discovery documents

- [api-catalog](https://wentogo.com/.well-known/api-catalog): RFC 9727 linkset tying the endpoint to its description and documentation.
- [oauth-protected-resource](https://wentogo.com/.well-known/oauth-protected-resource): RFC 9728 resource metadata.
- [agent-skills index](https://wentogo.com/.well-known/agent-skills/index.json): versioned skill files with digests.

## Data for planning

- [Countries index](https://wentogo.com/countries/): every country and destination slug.
- [planner-countries.json](https://wentogo.com/planner-countries.json): the same catalogue as data.