For developers
One endpoint, zero setup.
Everything WenToGo knows about a set of travel dates is one GET away. There is no key to provision, no SDK to install and no environment to distinguish, because the API is read-only and answers the same for everyone.
Reference
The resources that describe the whole API.
OpenAPI 3.1
The specification
Parameters, response schemas and the structured error model for the one endpoint, with no authentication to declare.
Openllms.txt
This section, scoped
A developer-only companion to the site-wide llms.txt: the API surface, conventions and quickstart in one short index.
Openauth.md
Authentication: none
The written statement that no page or endpoint wants a key, token or Authorization header.
OpenRFC 9727
API catalogue
The linkset that ties the endpoint to its OpenAPI description, its documentation and its metadata.
Openllms.txt
The whole site
The URL grammar for browsing pages, when a page beats the API, and every machine-readable file in one index.
OpenJSON
Skills index
Versioned skill files for dated, monthly and comparison questions, each with a content digest.
OpenQuickstart
Score one trip by asking for its dates. Country and destination are lowercase slugs; dates are inclusive ISO YYYY-MM-DD.
curl https://wentogo.com/api/trip/japan/tokyo/2027-04-01/2027-04-08
The response is JSON with a source_version, the scored trip and the factor breakdown. The same inputs on the same version return the same bytes, so cache by URL plus source_version and refetch only when the version moves.
The HTML twin of that answer lives at /trip/japan/tokyo/2027-04-01/2027-04-08: same verdict, written for people. Several browse pages also answer in Markdown when you send Accept: text/markdown, and every Markdown page is fetchable by appending .md to its URL.
Errors, limits and retries
Every origin error is JSON in one shape: {source_version, error: {code, message}} with a stable code such as UNKNOWN_DESTINATION or INVALID_DATE. An unknown /api/ path returns the same shape with NOT_PART_OF_PUBLIC_API, so a typo never hands you an HTML error page.
Fair use is enforced at the edge: 20 requests per 10 seconds per client IP across all /api/ paths, then a 429. Prerendered pages carry no limit, so prefer them for browsing. On a 429, wait the ten-second window and retry.
Every operation is a read-only GET, which makes the whole API idempotent by construction: a retry can never duplicate a booking, a charge or a record, because there is nothing to duplicate.
No key, no sandbox, nothing to sign up for
There is no free tier to buy, no API key to generate and no sandbox to point at, because the production API already is the safe environment: it reads a versioned data export, mutates nothing and bills nothing. If you can fetch this page, you have production access.
Need a destination list before you plan? /countries/ indexes every country and destination, and /planner-countries.json is the same catalogue as data.
Small timing, big difference.
