OpenTelemetry

PRX supports OpenTelemetry (OTLP) for distributed tracing. Traces provide span-level visibility into agent operations, including LLM calls, tool executions, and memory operations.

Overview

Each agent operation creates a trace with nested spans:

Session
  └── Turn
       ├── Memory Recall (span)
       ├── LLM Request (span)
       │    ├── Token Streaming
       │    └── Response Parsing
       └── Tool Execution (span)
            ├── Policy Check
            └── Sandbox Run

Configuration

[observability.tracing]
enabled = false
endpoint = "http://localhost:4317"  # OTLP gRPC endpoint
protocol = "grpc"  # "grpc" | "http"
service_name = "prx"
sample_rate = 1.0  # 0.0 to 1.0

Supported Backends

PRX can export traces to any OTLP-compatible backend:

• Jaeger
• Grafana Tempo
• Honeycomb
• Datadog
• AWS X-Ray (via OTLP collector)

Span Attributes

Common attributes attached to spans:

Attribute	Description
prx.session_id	Agent session identifier
prx.provider	LLM provider name
prx.model	Model identifier
prx.tool	Tool name (for tool spans)
prx.tokens.input	Input token count
prx.tokens.output	Output token count

Related Pages

• Observability Overview
• Prometheus Metrics