Function instrument

instrument<Env, QueueMessage = unknown>(
handler: ExportedHandler<Env, QueueMessage>,
options?: InstrumentOptions<Env>,
): ExportedHandler<Env, QueueMessage>
Wrap a Cloudflare Workers handler with automatic tracing
- fetch: extracts traceparent from request headers, or creates root span
- queue: extracts traceparent from message body (_traceparent field), or creates root span
- scheduled: generates new root span for each invocation
Type Parameters
- Env
- QueueMessage = unknown
Parameters
- handler: ExportedHandler<Env, QueueMessage>
- Optionaloptions: InstrumentOptions<Env>
Returns ExportedHandler<Env, QueueMessage>
Example
```
// Basic usage (no export, just context propagation)
export default instrument({
  async fetch(request, env, ctx) {
    const logger = getLogger();
    logger.info('handling request'); // includes trace_id, span_id
    return new Response('OK');
  },
});
```
Example
```
// With typed queue messages
interface MyMessage {
  orderId: string;
  _traceparent?: string;
}

export default instrument<Env, MyMessage>({
  async queue(batch, env, ctx) {
    for (const msg of batch.messages) {
      console.log(msg.body.orderId); // typed!
    }
  },
});
```
- Defined in instrument.ts:799