---
title: "Observability"
description: "Track session activity with OpenTelemetry."
icon: "chart-line"
---

Use OpenTelemetry to instrument session traffic, then ship telemetry to your collector/backend.

## Common collectors and backends

- [OpenTelemetry Collector](https://opentelemetry.io/docs/collector/)
- [Jaeger](https://www.jaegertracing.io/)
- [Grafana Tempo](https://grafana.com/oss/tempo/)
- [Honeycomb](https://www.honeycomb.io/)
- [Datadog APM](https://docs.datadoghq.com/tracing/)

## Example: trace a prompt round-trip

Wrap `session.prompt()` in a span to measure the full round-trip, then log individual events as span events.

Assumes your OTEL provider/exporter is already configured.

```ts
import { trace } from "@opentelemetry/api";
import { SandboxAgent } from "sandbox-agent";

const tracer = trace.getTracer("my-app/sandbox-agent");

const sdk = await SandboxAgent.connect({
  baseUrl: process.env.SANDBOX_URL!,
});

const session = await sdk.createSession({ agent: "mock" });

// Log each event as an OTEL span event on the active span
const unsubscribe = session.onEvent((event) => {
  const activeSpan = trace.getActiveSpan();
  if (!activeSpan) return;

  activeSpan.addEvent("session.event", {
    "sandbox.sender": event.sender,
    "sandbox.event_index": event.eventIndex,
  });
});

// The span covers the full prompt round-trip
await tracer.startActiveSpan("sandbox_agent.prompt", async (span) => {
  span.setAttribute("sandbox.session_id", session.id);

  try {
    const result = await session.prompt([
      { type: "text", text: "Summarize this repository." },
    ]);
    span.setAttribute("sandbox.stop_reason", result.stopReason);
  } catch (error) {
    span.recordException(error as Error);
    throw error;
  } finally {
    span.end();
  }
});

unsubscribe();
```
