# Minimal provider example

Provider packages can publish widget lines without importing `pi-widget-host`. They only need to write a `ProviderEntry` into the process-local registry on `globalThis`.

```ts
const registrySymbol = Symbol.for("pi-widget-host.registry.v1");

type ProviderEntry = {
  providerId: string;
  available: boolean;
  lines: string[];
  updatedAt: string;
  priority?: number;
  tags?: string[];
  mode?: string;
  ttlMs?: number;
};

type WidgetHostRegistry = {
  set(entry: ProviderEntry): void;
};

const registry = Reflect.get(globalThis, registrySymbol) as WidgetHostRegistry | undefined;

registry?.set({
  providerId: "example.now-playing",
  available: true,
  lines: ["Now Playing", "Example Artist — Example Song"],
  updatedAt: new Date().toISOString(),
  priority: 20,
  tags: ["music", "playing-now"],
});
```

Required fields are `providerId`, `available`, `lines`, and `updatedAt`. Optional fields such as `priority`, `tags`, `mode`, and `ttlMs` help the host choose between eligible providers. See [`protocol.md`](protocol.md) for the full registry shape and host selection notes.