Logfire Observability

This example instruments an Agno-Go agent with OpenTelemetry and forwards spans to Logfire. It is useful when you want to correlate reasoning content, token usage, and tool activity inside your observability platform.

Requirements

• Go 1.21+
• OpenAI API key (or another reasoning-capable provider)
• Logfire write token (LOGFIRE_WRITE_TOKEN)
• Optional: custom OTLP endpoint (LOGFIRE_OTLP_ENDPOINT defaults to logfire-eu.pydantic.dev)

Run

export OPENAI_API_KEY=sk-your-key
export LOGFIRE_WRITE_TOKEN=lf_your_token
go run -tags logfire cmd/examples/logfire_observability/main.go

Note
The example is guarded by the logfire build tag to avoid pulling OpenTelemetry dependencies during normal builds.

What the Example Does

1. Configures an OTLP/HTTP exporter with TLS and the Logfire write token.
2. Runs a reasoning-capable agent (OpenAI o1 preview by default).
3. Records span attributes for runtime, loop count, and token usage.
4. Emits a reasoning.complete span event containing the reasoning snippet (and optional redacted content).

In Logfire you will see spans similar to:

• agent.run
  • Attributes: agent.model, agent.provider, agent.duration_ms, agent.usage.*
  • Events: reasoning.complete with reasoning.content, reasoning.token_count

Related Docs

• docs/release/logfire_observability.md – deep dive guide (GitHub).
• website/advanced/observability.md – overview of the observability stack, including the SSE event stream.