Test Phoenix as OTel export target for eval results

[christso]

Context

AgentV already supports OTel export via export_otel and otel_backend config fields. Arize Phoenix is an open-source AI observability platform built natively on OpenTelemetry that provides tracing, evaluation visualization, dataset management, and experiment tracking.

Since both tools speak OTel, Phoenix should work as an export target with minimal or no code changes.

Tasks

• Spin up a local Phoenix instance (pip install arize-phoenix && phoenix serve)
• Configure an AgentV eval with export_otel: true pointing at Phoenix's OTLP endpoint
• Run an eval and verify traces appear in Phoenix UI
• Verify eval scores/annotations are correctly mapped
• Test otel_backend: 'phoenix' as a named backend option (if needed)
• Document Phoenix as a supported export target in docs

Expected Outcome

Phoenix shows up as a zero-config observability backend for AgentV eval results. Users get tracing, dashboards, and experiment tracking for free by pointing OTel at Phoenix.

Notes

• Phoenix OTLP endpoint is typically http://localhost:6006/v1/traces
• May need no code changes at all — just validation and docs
• Research: https://github.com/Arize-ai/phoenix