> ## Documentation Index
> Fetch the complete documentation index at: https://eo.utopy.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# OpenTelemetry

> Export effect-orpc procedure spans through Effect's OpenTelemetry integration.

`effect-orpc` creates Effect spans around procedures. To export them, include an OpenTelemetry layer in your application runtime.

## Install OpenTelemetry packages

```bash title="Install packages" theme={null}
bun add @effect/opentelemetry @opentelemetry/exporter-trace-otlp-http @opentelemetry/sdk-trace-base
```

## Create a tracing layer

```ts title="tracing.ts" theme={null}
import { NodeSdk } from "@effect/opentelemetry";
import { OTLPTraceExporter } from "@opentelemetry/exporter-trace-otlp-http";
import { BatchSpanProcessor } from "@opentelemetry/sdk-trace-base";

const NodeSdkLive = NodeSdk.layer(() => ({
  resource: { serviceName: "my-api" },
  spanProcessor: new BatchSpanProcessor(
    new OTLPTraceExporter({
      url: "http://localhost:4318/v1/traces",
    }),
  ),
}));
```

## Add it to your runtime

```ts title="runtime.ts" theme={null}
const AppLive = Layer.mergeAll(UsersRepoLive).pipe(
  Layer.provideMerge(NodeSdkLive),
);

export const runtime = ManagedRuntime.make(AppLive);
export const effectProcedure = makeEffectORPC(runtime);
```

## Customize procedure span names

```ts title="custom-span.ts" theme={null}
const getUser = effectProcedure
  .traced("users.get_by_id")
  .input(z.object({ id: z.string() }))
  .effect(function* ({ input }) {
    const usersRepo = yield* UsersRepo;
    return yield* usersRepo.findById(input.id);
  });
```

## Local collector

The repository Hono example includes an optional telemetry stack.

```bash title="Run collector" theme={null}
cd examples/hono
docker compose up
```

## Next step

Review the [Tracing capability](/effect-v4/capabilities/tracing) for how spans are named by default.