LLM observability: Observability: Traces Across Prompt, Retrieval, Tools

from opentelemetry import trace
tracer = trace.get_tracer("ai.gateway")

def handle_turn(req):
    with tracer.start_as_current_span("agent.turn") as root:
        root.set_attribute("session.id", req.session_id)
        with tracer.start_as_current_span("retrieve") as sp:
            chunks = retrieve(req.question)
            sp.set_attribute("retrieve.k", len(chunks))
            sp.set_attribute("index.sha", INDEX_SHA)
        with tracer.start_as_current_span("converse") as sp:
            sp.set_attribute("model.id", MODEL)
            out = converse(...)
            sp.set_attribute("usage.input_tokens", out["usage"]["inputTokens"])
        with tracer.start_as_current_span("cite.gate") as sp:
            gated = gate(out, chunks)
            sp.set_attribute("cite.ok", not gated.get("refuse"))
        return gated