Connect to the AX MCP Server

The MCP server is hosted, so there is nothing to install. You need the endpoint for your region and a way to authenticate: either sign in with your Arize account (OAuth) or use an Arize API key. Every request sends the credential as Authorization: Bearer <token>. The Bearer prefix is required. The URLs on this page use the US endpoint, https://api.arize.com/mcp. If your account is in the EU or CA region, use your regional URL from the endpoints page instead.

Add the server to your client

Claude Code
Claude Desktop
Cursor
Codex
Other clients

Registering at project scope writes to .mcp.json in the repository root:

claude mcp add-json arize-ax --scope project '{
  "type": "http",
  "url": "https://api.arize.com/mcp",
  "headers": {"Authorization": "Bearer ${ARIZE_API_KEY}"}
}'

Use --scope user instead to make the server available in every project on your machine.

Check the connection

Run claude mcp list, which shows whether each server connected, or run /mcp inside Claude Code for interactive status.

Remove it (optional)

Run claude mcp remove arize-ax.

Cursor requires an API key in the Authorization header. OAuth sign-in is not supported there.

Add the server

Go to Settings → MCP → Add new global MCP server, then add this entry to the JSON config:

"arize-ax": {
  "type": "http",
  "url": "https://api.arize.com/mcp",
  "headers": {"Authorization": "Bearer ${ARIZE_API_KEY}"}
}

Restart Cursor

Restart Cursor if the tools do not appear.

OAuth
API key

codex mcp add arize-ax --url https://api.arize.com/mcp --oauth-client-id codex

codex mcp login arize-ax

Check the connection

Run codex mcp get arize-ax, or list every configured server with codex mcp list. Remove it with codex mcp remove arize-ax.

codex mcp add arize-ax --url https://api.arize.com/mcp --bearer-token-env-var ARIZE_API_KEY

This writes to ~/.codex/config.toml. --bearer-token-env-var points Codex at the variable name, so the key itself never lands in the file. Codex sends it as Authorization: Bearer <value> on every request.You can also edit config.toml directly:

[mcp_servers.arize-ax]
url = "https://api.arize.com/mcp"
bearer_token_env_var = "ARIZE_API_KEY"

Check the connection

Run codex mcp get arize-ax, or list every configured server with codex mcp list. Remove it with codex mcp remove arize-ax.

Any client that speaks Streamable HTTP and supports custom headers works. The config shape is the same:

{
  "mcpServers": {
    "arize-ax": {
      "type": "http",
      "url": "https://api.arize.com/mcp",
      "headers": {"Authorization": "Bearer ${ARIZE_API_KEY}"}
    }
  }
}

Some clients expand ${...} from your environment and some do not. If the connection fails with an auth error, replace the placeholder with the key directly to rule it out.A few clients take a top-level "auth" field instead of headers and send it as Authorization: Bearer <key> for you.

Verify the connection

Ask your agent something that requires a tool call, such as “list my Arize projects.” It should call list_projects and come back with names rather than a guess. To test outside a client, use the MCP Inspector CLI. It needs Node 22.19.0 or newer and runs through npx with no install:

npx @modelcontextprotocol/inspector --cli https://api.arize.com/mcp \
  --transport http \
  --header "Authorization: Bearer $ARIZE_API_KEY" \
  --method tools/list \
  --format json | jq .result

Call a tool the same way:

npx @modelcontextprotocol/inspector --cli https://api.arize.com/mcp \
  --transport http \
  --header "Authorization: Bearer $ARIZE_API_KEY" \
  --method tools/call \
  --tool-name list_projects \
  --tool-arg name=my-project \
  --format json | jq .result

The CLI exits non-zero on failure. Exit code 3 means authentication failed and exit code 4 means the server was unreachable.

Troubleshooting

Connection errors such as 401, 404, 429, and timeouts are covered in the FAQ.

Next steps

Endpoints

Regional URLs for the MCP server.

Authentication

Tool catalog

Every tool your agent can now call, with arguments and pagination rules.

Skills

Run scripted workflows for datasets, experiments, evaluators, and prompt optimization. Skills and the CLI suit repeatable jobs.

Skills

MCP server

API reference

API clients

Connect to the AX MCP Server

Add the server to your client

Verify the connection

Troubleshooting

Next steps

Endpoints

Authentication

Tool catalog

Skills

​Add the server to your client

​Verify the connection

​Troubleshooting

​Next steps

Endpoints

Authentication

Tool catalog

Skills

Add the server to your client

Verify the connection

Troubleshooting

Next steps