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

# Observability

> Track sessions, debug agent runs, analyze cost, and export events to your own observability stack.

Herm gives you two observability surfaces:

* The **Herm web app** for tracking sessions, inspecting debug events, and
  understanding cost and usage across your workspace.
* The **Sessions API** for exporting the same session events and usage
  snapshots into tools such as Langfuse, Datadog, Honeycomb, or your internal
  logging pipeline.

## Track sessions in the web UI

Open **Sessions** in the Herm app to see the runs created by your agents. Each
session is tied to an agent, a subject, lifecycle timestamps, transcript
history, and usage data when available.

```
https://herm.run/app/sessions
```

Use this view when you want to review what happened across all customer-facing
or internal agent sessions without building your own admin console first.

## Debug a session

Every session detail page includes a **Debug** view. Use it to inspect the raw
event stream behind a conversation, including user messages, agent messages,
reasoning, tool calls, tool results, approvals, status changes, and usage
snapshots.

The debug view is useful when you need to answer questions such as:

* Which tool did the agent call?
* What result came back from that tool?
* Did the turn stop because it finished, needed approval, or required a custom
  tool result?
* How much context, latency, and estimated cost did the turn use?

## Analyze cost and usage

Session details show cost and usage data when Herm has a usage snapshot for the
run. Usage can include tokens, context window percentage, model calls, latency,
estimated cost, and cost status.

For the raw usage shape, see
[Usage snapshots](/api-reference/stream-events#usage-snapshots).

## Use the dashboard

The Herm dashboard aggregates workspace-level activity so you can monitor agent
usage over time. Use it for a quick read on active sessions, message volume,
agent activity, and usage trends before drilling into an individual session.

```
https://herm.run/app
```

## Export to another provider

If your team already uses an observability product, stream Herm events from your
backend and forward them into that system.

Use:

* [List events](/api-reference/stream-events#list-events) for durable history.
* [Stream events](/api-reference/stream-events#stream-events) for live updates.
* [Events Reference](/api-reference/events-reference) for event schemas.

For example, you can forward terminal turn events with `usage` into Langfuse for
per-generation token, cost, model, and latency reporting. You can also forward
tool-call events into Datadog, Honeycomb, or your own logs to reconstruct each
agent run end to end.

Keep the Herm `sessionId`, `turnId`, event `id`, and event `sequence` on any
external record you create. Those fields let you jump back from your external
observability tool to the source session in Herm.