Choose a telemetry exporter

Instrument the execution object or its event bus, then choose where the completed trace goes. By default, capture retains lifecycle metadata and usage while omitting prompt text, tool arguments/results, response text, and error bodies.

Exporter	Destination	Choose when
`ConsoleExporter` / `"console"`	Console trace tree	Inspect a local application
`JsonFileExporter` / `"json-file"`	Compact append-only JSONL	Retain local structured traces
`CallbackExporter`	Host callback	Feed an existing internal sink
OTelExporter / `"otel"`	OTLP over HTTP JSON	Send directly to a compatible collector
OTelBridgeExporter	Host-owned OTel tracer	Use your SDK’s sampling, processors, or binary exporter
LangfuseOTLPExporter / `"langfuse-otlp"`	Langfuse OTLP ingestion	Use the current Langfuse integration
`LangfuseExporter` / `"langfuse"`	Legacy ingestion	Maintain an explicitly compatible older integration; emits a migration diagnostic

Write JSONL traces

npm install @agentium/core@4.0.0 @agentium/observability@4.0.0 openai

This complete example requires OPENAI_API_KEY and a TypeScript runner. It makes a model call and appends a metadata trace to traces.jsonl.

traces.ts

import { Agent, openai } from "@agentium/core";
import { instrument, JsonFileExporter } from "@agentium/observability";

const agent = new Agent({ name: "traced-agent", model: openai(process.env.OPENAI_MODEL ?? "gpt-6-luna") });
const observation = instrument(agent, { exporters: [new JsonFileExporter({ path: "traces.jsonl" })] });
try {
  const result = await agent.run("Say hello in one sentence.");
  console.log(result.status, result.text);
} finally {
  await observation.shutdown();
  await agent.close();
}

Observe a harness

Pass an EventBus as HarnessRuntime.telemetry and attach instrumentBus(bus, options) to observe runtime/direct model and controller calls. Keep Agent-driver instrumentation on its own bus to avoid counting a call twice. A tool event or missing trace is not evidence of whether an external effect happened; use application records for that.

Capture and shutdown

Choosing an exporter does not opt into content. If you need content, set an explicit bounded capture/redaction policy at both instrumentation and each explicit exporter instance. See capture policy. Export queues and retention are bounded. Slow exporters do not block the Agent’s outcome; drops and export errors appear as diagnostics. Call shutdown() after active work settles to detach and drain within its deadline. The host still owns external providers and clients it supplied.

Find an integration

Voice and call adapters

Sandbox and telemetry

Providers and services

Protocols and devices

Choose a telemetry exporter

Write JSONL traces

Observe a harness

Capture and shutdown

​Write JSONL traces

​Observe a harness

​Capture and shutdown

Write JSONL traces

Observe a harness

Capture and shutdown