Connect a client

The server URL is the same for everyone:

https://app.rerun.build/api/mcp/account

It is an HTTP MCP server. Every snippet below sends your key in an Authorization header. The app shows these same snippets with your real key already filled in, right after you create it, under the workspace pill then API keys & MCP.

Replace rk_your_key with the key you copied. See Authentication if you do not have one yet.

Claude Code

claude mcp add --transport http rerun https://app.rerun.build/api/mcp/account --header "Authorization: Bearer rk_your_key"

Then ask Claude Code what it can do with Rerun. It calls tools/list on its own and discovers the 45 tools.

Codex

Codex reads the key from the environment each time it starts the server, so export it first.

export RERUN_MCP_KEY="rk_your_key"
codex mcp add rerun --url https://app.rerun.build/api/mcp/account --bearer-token-env-var RERUN_MCP_KEY

This is the Codex CLI. The ChatGPT app only accepts OAuth connectors, so an API key gets you nowhere there.

Cursor

Add the server to ~/.cursor/mcp.json:

~/.cursor/mcp.json

{
  "mcpServers": {
    "rerun": {
      "url": "https://app.rerun.build/api/mcp/account",
      "headers": {
        "Authorization": "Bearer rk_your_key"
      }
    }
  }
}

A Rerun agent

You can give one of your own agents the same reach over the workspace as an outside client. Open the agent panel, go to the MCP tab, click New, and paste:

{
  "name": "rerun",
  "transport": "http",
  "url": "https://app.rerun.build/api/mcp/account",
  "headers": {
    "Authorization": "Bearer rk_your_key"
  }
}

This lets that agent create, edit and delete every other agent of the workspace, including itself. Do it on purpose, and prefer a dedicated agent for it.

Any other client

Point the client at the URL and add the header.

Field	Value
Server URL	`https://app.rerun.build/api/mcp/account`
Transport	HTTP
Header	`Authorization: Bearer rk_your_key`

For a client that only speaks stdio, bridge it:

npx -y mcp-remote https://app.rerun.build/api/mcp/account --header "Authorization: Bearer rk_your_key"

Check the connection

The cheapest call that proves everything works is tools/list.

curl -s https://app.rerun.build/api/mcp/account \
  -H "Authorization: Bearer rk_your_key" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

A 401 Unauthorized in plain text means the key is missing, malformed or revoked. Anything else comes back as JSON-RPC. See Protocol for the full handshake.

Get started

Tool reference

HTTP

Connect a client

Claude Code

Codex

Cursor

A Rerun agent

Any other client

Check the connection

​Claude Code

​Codex

​Cursor

​A Rerun agent

​Any other client

​Check the connection

Claude Code

Codex

Cursor

A Rerun agent

Any other client

Check the connection