Sessions

A session groups every trace that shares a sessionId — a multi-turn chat, a support thread, or a long-running agent run. Sessions turn a stream of individual requests into one reviewable timeline. Served by Hanzo O11y, tenant-scoped by org.

Starting a session

There is no "create session" call — a session comes into existence the moment a trace carries a sessionId. Set it as an OpenTelemetry attribute (or the trace field) and reuse the same value across turns.

with tracer.start_as_current_span("chat.turn") as span:
    span.set_attribute("session.id", "sess_9f")   # groups this trace into the session
    span.set_attribute("user.id", "u_42")
    respond(message)

Related

• Traces — the individual requests a session groups
• Scores — evaluations can be attached at the session level
• O11y — the observability platform behind sessions