
Arize Phoenix MCP Server
MCPConnects to the Arize Phoenix observability platform so agents can query LLM traces and sessions, manage prompts, browse datasets and read experiment evaluation results. Maintained by Arize; needs a self-hosted or cloud Phoenix instance.
Phoenix MCP Server is an implementation of the Model Context Protocol for the Arize Phoenix platform. It provides a unified interface to Phoenix's capabilities.
You can use Phoenix MCP Server for:
- Projects Management: List and explore projects that organize your observability data
- Traces, Spans & Annotations: Retrieve traces, spans, and annotation configs for analysis and debugging
- Sessions: Explore conversation flows and session-level annotations
- Prompts Management: Create, list, update, and iterate on prompts
- Datasets: Explore datasets and synthesize new examples
- Experiments: Pull experiment results and visualize them with the help of an LLM
Don't see a use-case covered? @arizeai/phoenix-mcp is open-source! Issues and PRs welcome.
Installation
This MCP server can be used with npx and can be directly integrated with clients like Claude Desktop, Cursor, and more.
{
"mcpServers": {
"phoenix": {
"command": "npx",
"args": [
"-y",
"@arizeai/phoenix-mcp@latest",
"--baseUrl",
"https://my-phoenix.com",
"--apiKey",
"your-api-key"
]
}
}
}
Development
Install
This package is managed via a pnpm workspace.
// From the /js/ directory
pnpm install
pnpm build
This only needs to be repeated if dependencies change or there is a change to the phoenix-client.
Building
To build the project:
pnpm build
Development Mode
To run in development mode:
pnpm dev
Debugging
You can build and run the MCP inspector using the following:
pnpm inspect
Environment Variables
When developing, the server requires the following environment variables:
PHOENIX_API_KEY: Your Phoenix API keyPHOENIX_ENDPOINT: The base URL for PhoenixPHOENIX_PROJECT: Optional default project for project-scoped tools (alias:PHOENIX_PROJECT_NAME)PHOENIX_CLIENT_HEADERS: Optional JSON-encoded request headers
Make sure to set these in a .env file. See .env.example.
At runtime the server also discovers the nearest .env.phoenix file at or
above the working directory. Process environment variables and command-line
options take precedence. If a higher-priority API key is paired with an
endpoint from the file, the server warns once and continues. Set
PHOENIX_DISCOVER_CONFIG=false to disable discovery.
Tool Coverage
The MCP server covers the main operational Phoenix workflows:
Prompts — list-prompts, get-prompt, get-latest-prompt, get-prompt-by-identifier, get-prompt-version, list-prompt-versions, get-prompt-version-by-tag, list-prompt-version-tags, add-prompt-version-tag, upsert-prompt
Projects — list-projects, get-project
Traces — list-traces, get-trace
Spans — get-spans, get-span-annotations
Sessions — list-sessions, get-session
Annotation Configs — list-annotation-configs
Datasets — list-datasets, get-dataset, get-dataset-examples, get-dataset-experiments, add-dataset-examples
Experiments — list-experiments-for-dataset, get-experiment-by-id
For Phoenix documentation search, use the separate Phoenix Docs MCP server instead of this package.
Community
Join our community to connect with thousands of AI builders:
- 🌍 Join our Slack community.
- 📚 Read the Phoenix documentation.
- 💡 Ask questions and provide feedback in the #phoenix-support channel.
- 🌟 Leave a star on our GitHub.
- 🐞 Report bugs with GitHub Issues.
- 𝕏 Follow us on 𝕏.
- 💼 Follow us on LinkedIn.
- 🗺️ Check out our roadmap to see where we're heading next.
License
Apache 2.0
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