@axon-ai/cli

The Axon CLI runs a local, OpenTelemetry-native LLM-observability stack — backend and dashboard on a single URL. Point any OTEL/OpenLLMetry exporter at it and watch your LLM/agent traces in real time. No Axon-specific SDK needed.

Install

npm install -g @axon-ai/cli

Quick start

axon start
#   ✔ Axon running at http://localhost:4000

Then send standard OpenTelemetry spans to http://localhost:4000. With OpenLLMetry (Node):

import * as traceloop from "@traceloop/node-server-sdk";
traceloop.initialize({ baseUrl: "http://localhost:4000" });
// use LangChain / OpenAI / Anthropic / LlamaIndex normally — traces appear in Axon

Or with a raw OTEL SDK: OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4000.

Open http://localhost:4000 (on Windows use http://127.0.0.1:4000 if localhost won't connect). Traces are stored per project under ./.axon-ai/traces.db.

Commands

axon start

Start Axon (backend + dashboard on one URL).

• -p, --port <port> — port to serve on (default: 4000)
• --no-open — don't open the browser automatically
• --project <name> — project name for organizing traces

axon status

Report whether Axon is running and on which port.

axon stop

Stop Axon.

axon version

Print the CLI version.

axon, axon-ai, and agent-trace are aliases for the same CLI.

The dashboard

Each trace offers four views:

• Transcript (default) — the run as a chat dialogue (user → model → tool → result).
• Tree — the span hierarchy with inline duration bars.
• Waterfall — duration bars on a shared time axis.
• Raw — the verbatim OTEL span JSON, with a copy button.

Plus a per-trace cost-by-model breakdown.

Troubleshooting

Port already in use — start on another port: axon start --port 5000, or stop the process holding 4000.

localhost won't connect (Windows) — open http://127.0.0.1:4000 instead; localhost may resolve to IPv6 while the server binds IPv4.

Migrating from the old tracer packages

@axon-ai/langchain-tracer and @axon-ai/openai-tracer are deprecated. Use standard OTEL instrumentation (OpenLLMetry / OpenInference) pointed at http://localhost:4000 instead.

License

MIT — see LICENSE.