feat(skills): ship a consumer skill with the package

package.json

@@ -17,7 +17,9 @@
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
   "files": [
-    "dist"
+    "dist",
+    "docs",
+    "skills"
   ],
   "exports": {
     ".": {
@@ -58,6 +60,9 @@
     "access": "public"
   },
   "antelopeJs": {
-    "test": "src/antelope.test.ts"
+    "test": "src/antelope.test.ts",
+    "skills": [
+      "./skills"
+    ]
   }
 }

skills/auth-interface/SKILL.md

@@ -0,0 +1,83 @@
+---
+name: auth-interface
+description: AntelopeJS interface for token-based authentication - signing and verifying auth tokens (SignRaw, ValidateRaw, SignServerResponse) and injecting the verified payload into interface-api controllers via the @Authentication decorator or custom decorators from CreateAuthDecorator. Use when code imports "@antelopejs/interface-auth", when securing controller routes, generating or validating auth/JWT tokens, injecting authenticated user data into handler parameters, or when implementing an auth provider for internal.Verify/internal.Sign.
+category: antelopejs-interface
+tags: [antelopejs, auth, jwt, tokens, decorators]
+---
+
+# @antelopejs/interface-auth
+
+Token authentication for AntelopeJS modules. Two layers:
+
+- **Proxy crossings** (need a provider module loaded, e.g. a JWT module): `internal.Verify` and `internal.Sign`, wrapped by `SignRaw`, `ValidateRaw`, and `SignServerResponse`. Always async.
+- **Consumer-side helpers** (no crossing by themselves): `Authentication` and `CreateAuthDecorator`, which build parameter providers on top of `@antelopejs/interface-api`.
+
+## Imports
+
+All symbols come from the package root (the exports map exposes no other code subpaths):
+
+```ts
+import {
+  Authentication, CreateAuthDecorator,
+  SignRaw, ValidateRaw, SignServerResponse,
+  internal, // provider side only
+  type AuthSource, type AuthVerifier, type AuthValidator,
+  type SignOptions, type VerifyOptions, type CookieOptions,
+} from "@antelopejs/interface-auth";
+```
+
+`@antelopejs/interface-api` and `@antelopejs/interface-core` are peerDependencies — the consuming module must have them installed.
+
+## Consuming
+
+```ts
+import { Controller, Get, Post } from "@antelopejs/interface-api";
+import { Authentication, SignRaw } from "@antelopejs/interface-auth";
+
+interface LibrarianSession { id: string; branch: string; }
+
+class LibrarianController extends Controller("/librarians") {
+  @Post("login")
+  async login() {
+    // Sign a payload into a token (proxy call to the auth provider)
+    return SignRaw({ id: "lib-7", branch: "riverside" }, { expiresIn: "1h" });
+  }
+
+  @Get("desk")
+  async getDesk(@Authentication() librarian: LibrarianSession) {
+    // Token was read from the request, verified, and injected
+    return { id: librarian.id, branch: librarian.branch };
+  }
+}
+```
+
+Custom pipelines use `CreateAuthDecorator({ source?, authenticator?, authenticatorOptions?, validator? })`; the callbacks run as `source(req, res)` → `authenticator(data, authenticatorOptions)` → `validator(data)` → injected parameter.
+
+## Providing
+
+An auth backend module implements the two proxy points:
+
+```ts
+import { ImplementInterface } from "@antelopejs/interface-core";
+import { internal } from "@antelopejs/interface-auth";
+
+ImplementInterface(internal, {
+  Verify: (token, options) => decodeAndVerify(token, options), // return payload, throw on invalid
+  Sign: (data, options) => signToken(data, options),           // return token string
+});
+```
+
+Declare `"antelopeJs": { "implements": ["@antelopejs/interface-auth"] }` in the provider's package.json.
+
+## Gotchas
+
+- `SignRaw` / `ValidateRaw` / `SignServerResponse` are interface proxy calls: they return Promises and only resolve once a provider module is attached. While a provider module is loaded but not yet attached, earlier calls are queued, not failed — always `await`. But when no loaded module provides the interface (e.g. a stubbed `optionalDependencies` entry), the core neutralizes the proxies and those calls reject instead of queuing.
+- Default token source (`internal.defaultSource`): the `x-antelopejs-auth` request header, falling back to the `ANTELOPEJS_AUTH` cookie. `SignServerResponse` sets that same cookie via `Set-Cookie`.
+- `@Authentication(validator?)` accepts an optional validator at the use site; it overrides any validator configured in `CreateAuthDecorator`.
+- Decorators from `CreateAuthDecorator` (including `Authentication`) apply to parameters, properties, and whole classes (class-level registers a provider for the controller) — NOT to methods; decorating a method silently registers nothing and can break other parameter decorators on that handler.
+- `expiresIn` / `notBefore` (SignOptions) and `maxAge` (VerifyOptions) accept a number of seconds or a timespan string such as `"1h"`.
+- Rejection is exception-based: a failed verification or validator throws, it does not return `undefined`.
+
+## Deeper reference
+
+See this package's `docs/` chapters — Introduction, Authentication Basics, Token Handling, Parameter Decoration — and the shipped `dist/index.d.ts` for full TSDoc signatures. Do not duplicate them here.