Phoenix v20.4.0 ships in-process MCP toolset and retrieval-relevance evaluator

Arize AI

Tools official 1 src. ~1 min

arize-phoenix v20.4.0 (Aug 26) introduces an in-process Phoenix MCP toolset for agents (so an eval/observability session can be driven from any MCP-capable agent), a retrieval-relevance evaluator, Gemini 3.7 Flash playground support, AI Query for trace-filter DSL, GET /model_providers REST endpoint, and PATCH /projects retention endpoint. The model providers endpoint was restructured but only affected unreleased clients. v3.5.1 of arize-phoenix-evals upgrades to Anthropic SDK v1.

Why it matters

Phoenix becoming an MCP server closes the loop between agent frameworks and observability — agents can query their own traces natively without bespoke adapters.

Importance: 2/5

default

phoenix arize observability mcp evals release

Sources

official Phoenix v20.4.0 release