Instrument Hermes Agent with Grafana observability traces

grafana-agento11y-hermes is a Grafana Agent Observability plugin for Hermes Agent. It records LLM calls and tool executions as generations and emits OpenTelemetry traces and metrics, so those interactions show up in Grafana Cloud's Observability -> Agent -> Conversations view. With no capture mode set, it records full content by default - the system prompt, tool definitions, prompts, assistant replies, tool arguments, and tool results all leave the machine - so setting AGENTO11Y_CONTENT_CAPTURE_MODE=metadata_only is the way to keep recording every call while no prompt, response, or tool I/O content leaves the machine.

Use it when running Hermes Agent and you want its LLM calls and tool executions visible as traces and metrics in Grafana Cloud, using the free tier if you don't already have a Grafana Cloud account. It replaces an earlier package, hermes-plugin-sigil: the package name, module, entry-point key, and environment variable prefix all changed from sigil/SIGIL_* to agento11y/AGENTO11Y_*, and upgrading requires uninstalling the old package explicitly, since pip would otherwise install the renamed package alongside the old one and register both as plugins. Hermes's own plugins enable CLI does not see pip-installed plugins yet - it only scans ~/.hermes/plugins/ and the bundled directory - so the plugin has to be enabled by editing ~/.hermes/config.yaml directly, and hermes plugins list won't confirm it either; the only way to confirm it's working is to check that data actually arrives in Grafana Cloud.

pip install grafana-agento11y-hermes

Install into the same Python environment Hermes runs from (check with which hermes), then enable it in ~/.hermes/config.yaml:

plugins:
  enabled:
    - agento11y

Credentials come from one setup page per Grafana stack (https://<stack>.grafana.net/a/grafana-agento11y-app/setup): create a token, copy it as environment variables, and put that block in the environment Hermes starts from (or ~/.hermes/.env, which Hermes loads with override on, so a value there beats the same variable exported in the shell with no warning). To verify, run AGENTO11Y_DEBUG=true hermes in interactive mode (one-shot hermes -z disables logging entirely) and check ~/.hermes/logs/agent.log for lines confirming the TracerProvider, MeterProvider, and client initialized, then ask Hermes anything and check the Conversations view in Grafana Cloud.

The plugin can also be installed by pasting an install prompt into Hermes, Claude, Codex, Cursor, or a similar agent capable of fetching a URL, which walks through the pip install, config file edit, and credential setup itself. It exports over OTLP HTTP to the endpoint and headers Grafana Cloud's setup page provides. Licensed under Apache-2.0.

Teams running Hermes Agent who want its LLM calls and tool usage observable as traces and metrics in Grafana Cloud, with explicit control over whether prompt and response content leaves the machine.