# Documentation

How Fylane works, what it returns, and what to do when it returns an error. Every page here also exists as Markdown — append `.md` to any URL.

> **Every page has a Markdown twin**
>
> Append `.md` to any documentation URL for the same content as CommonMark. Both are rendered from one source, so they cannot disagree. The machine-readable contract is at `/openapi.json`.

## Start here

- [Quickstart](/docs/quickstart) — Upload a file, ask for an operation, receive the result. Three calls, none of which block on the work.
- [Concepts](/docs/concepts) — Files, jobs, artifacts and credits — the four nouns the whole API is built from, and how they relate.

## Reference

- [API reference](/docs/api) — Every endpoint, generated from the OpenAPI document.
- [Uploads](/docs/api/uploads) — Getting bytes into Fylane without them touching the API.
- [Jobs](/docs/api/jobs) — Asking for work and finding out how it went.
- [Files](/docs/api/files) — Stored files and the artifacts derived from them.
- [Webhooks](/docs/api/webhooks) — Signed delivery of events, so you do not have to poll.
- [Usage](/docs/api/usage) — Credits, storage and egress for the current period.
- [Errors](/docs/errors) — Every code the API can return, and whether retrying helps.