Cardea

Features

• Provides a CLI with parameters and options similar to docker
• Connects to a remote server via SSE and exposes it as a stdio server
• Connects to a local server via stdio and exposes it as an SSE server
• Implements an SSE server that acts as a proxy, forwarding events from a remote SSE server

Usage

Quick install

curl -sSfL 'https://raw.githubusercontent.com/cardea-mcp/cardea-cli/refs/heads/master/install.sh' | sudo bash

Or, download the pre-built binary for your platform. Unzip and drop the cardea binary anywhere in your path.

Building from source

cargo build --release

Running

The proxy can operate in three modes:

1. SSE Client Mode

Connect to a remote MCP server over SSE and expose it as a stdio server.

This allows a local client such as Claude or Cursor connect to a remote server running on SSE.

cardea run -p remote_sse_server_host:remote_sse_server_port/sse

2. Stdio Client Mode

Connect to a local command using stdio and expose it as an SSE server.

This allows remote SSE connections to a local stdio server.

cardea run -p exposed_ip:exposed_port your-command
cardea run -p exposed_ip:exposed_port -e KEY=VALUE your-command

cardea run -p 8000 npx -y @modelcontextprotocol/server-everything

3. Proxy Mode

Connect to a remote MCP server over SSE and expose it as an SSE server.

This allows remote SSE connections proxy to other remote server.

cardea run -p exposed_ip:exposed_port:remote_sse_server_host:remote_sse_server_port/sse

Self testing

// Launch in Stdio Client Mode
cardea run -p 8000 npx -y @modelcontextprotocol/server-everything

// Launch in Proxy Mode, connecting to the SSE server launched above
cardea run -p 8001:http://127.0.0.1:8000/sse

// Run the inspector to verify SSE servers on ports 8000 and 8001
npx @modelcontextprotocol/inspector

Security

Use cardea run --security in the same way as cardea run, with all other parameters unchanged.

The process for obtaining the authentication token is described in the diagram below.

Setup the API Key Server

# Alpha version, please build from source for the latest version
git clone https://github.com/cardea-mcp/api-key-generator
cd api-key-generator
# Build the API Key Server
cargo build --release

# Run the API Key Server
./target/release/api-key-server
# Run the HTTP Server for generating API keys
python3 -m http.server 8080

Obtain the API Key

1. Open the HTTP Server in your browser: http://localhost:8080
2. Click on the "Generate API Key" button.
3. Copy the generated API key sk_... from the page.

Start the Cardea CLI with Security

# cardea run --security -p exposed_ip:exposed_port your-command
# Take memory MCP as an example
cardea run --security -p 8000 npx -y @modelcontextprotocol/server-memory

Connect to the MCP Server with the API Key

1. Start the MCP client

   # Use inspector as an example
   npx @modelcontextprotocol/inspector
   

2. Set the URL: http://localhost:8000/sse
3. Click on the "Authentication" button.
4. Paste the API key sk_... into the Bearer Token field.
5. Click on the "Connect" button.