# Reference

> Reference for every scafo surface: the CLI, the node API, the ingress protocol, the Caddy modules, the registry layout and the error codes.

| Page | Contents |
| --- | --- |
| [CLI](/reference/cli) | Every `scafo` command and subcommand: usage, arguments, flags, what each talks to, exit behaviour. |
| [Node API](/reference/node-api) | Every HTTP route of the node daemon: method, path, auth, request, response, status codes. |
| [Ingress protocol](/reference/ingress-protocol) | The routing document, `prefer` and ordering rules, denied paths, the Traefik rendering, and the storage protocol. |
| [Caddy modules](/reference/caddy-modules) | `scafo-ingress`: module IDs, builds, images, DNS providers, options, request variables, worked Caddyfile. |
| [Registry](/reference/registry) | Bucket key layout, record JSON shapes, CAS operations, celld fleet prefix, observation keys, TLS prefixes. |
| [Errors](/reference/errors) | Problem-document format, every error code and its HTTP status, CLI rendering, ingress failure values. |

::note
Configuration settings — flags, environment variables and config-file keys — are documented under [/config](/config). This section documents surfaces, not settings.
::