Phoenix phoenix-pxi

Development guide for the Phoenix PXI agent. Use when modifying PXI-specific frontend or backend behavior, extending PXI tool wiring, updating PXI runtime capabilities, or changing the PXI agent request/dispatch flow. Start here for PXI-specific workflows, then read the relevant resource file for the layer you are changing.

install

source · Clone the upstream repo

git clone https://github.com/Arize-ai/phoenix

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/Arize-ai/phoenix "$T" && mkdir -p ~/.claude/skills && cp -r "$T/.agents/skills/phoenix-pxi" ~/.claude/skills/arize-ai-phoenix-phoenix-pxi && rm -rf "$T"

manifest: .agents/skills/phoenix-pxi/SKILL.md

source content

Phoenix PXI Development

Phoenix has a built-in AI assistant named PXI (pronounced "pixie"). PXI is the user-facing name for the assistant feature — backend configuration (env vars, project names) uses generic

agents

assistant

naming, not "PXI".

Composable guidance for extending PXI across the Phoenix codebase.

Before changing PXI behavior, identify which layer you are working in and read the relevant resource file.

Resources

Read the relevant file(s) based on the task:

Resource file	When to read
`resources/extending-frontend-tool-registry.md`	Adding, editing, or removing a frontend-executed PXI tool; changing capability-gated tool behavior; updating request/dispatch flow for frontend tools
`resources/system-prompt-xml-conventions.md`	Adding to, editing, or reviewing the PXI agent system prompt, any `*ToolCapabilities.ts` module, or cross-cutting output-format guidance

Verification

Use layer-appropriate verification for the PXI surface you touched.

Refer to the makefile for verification commands.