composer-mcp-server 0.1.1

Composer MCP Server - Backtest and Automate your trades with LLMs

Official Composer Model Context Protocol (MCP) server that allows MCP-enabled LLMs like Claude Desktop, Cursor, OpenAI Agents and others to validate investment ideas via backtests and even trade multiple strategies (called "symphonies") in parallel to compare their live performance.

Features

• Create automated investing strategies
  • Use indicators like Relative Strength Index (RSI), Moving Average (MA), and Exponential Moving Average (EMA) with a diverse range of equity and crypto offerings to build your ideal portfolio.
  • Don't just make one-off trades. Composer symphonies constantly monitor the market and rebalance accordingly.
  • Try asking Claude: "Build me a crypto strategy with a maximum drawdown of 30% or less."
• Backtest your ideas
  • Our Backtesting API provides a fast feedback loop for AI to iterate and validate its hypotheses.
  • Try asking Claude: "Compare the strategy's performance against the S&P 500. Plot the results."
• Monitor performance (requires API Key)
  • View performance statistics for your overall account as well as for individual symphonies.
  • Try asking Claude: "Identify my best-performing symphonies. Analyze why they are working."
• Control your investments (requires API Key + Composer subscription)
  • Ask AI to analyze your investments and adjust your exposure accordingly!
  • Try asking Claude: "Research the latest trends and news. Analyze my symphonies and determine whether I should increase / decrease my investments."

Quickstart with Claude Desktop

This section will get you started with creating symphonies and backtesting them. You don't even need a Composer account to use these features!

Note that other tools will require an API Key.

1. Install uv (Python package manager) with curl -LsSf https://astral.sh/uv/install.sh | sh or see the uv repo for additional install methods.
2. Go to Claude > Settings > Developer > Edit Config > claude_desktop_config.json to include the following:

{
  "mcpServers": {
    "composer": {
      "command": "uvx",
      "args": [
        "composer-mcp-server"
      ]
    }
  }
}

3. If this doesn't work, check the "Spawn uvx ENOENT" section below.
4. That's it. Your MCP client can now interact with Composer! Try asking Claude something like, "Create and backtest a basic 60-40 strategy."

If you're using Windows, you will have to enable "Developer Mode" in Claude Desktop to use the MCP server. Click "Help" in the hamburger menu at the top left and select "Enable Developer Mode".

Getting your API Key

An API key will be necessary to interact with your Composer account. For example, saving a Composer Symphony for later or viewing statistics about your portfolio.

Trading a symphony will require a paid subscription, although you can always liquidate a position regardless of your subscription status. Composer also includes a 14-day free trial so you can try without any commitment.

Get your API key from Composer by following these steps:

1. If you haven't already done so, create an account.
2. Open your "Accounts & Funding" page
3. Request an API key
   
4. Save your API key and secret
   
5. Modify your claude_desktop_config.json to include your API key and secret:

{
  "mcpServers": {
    "composer": {
      "command": "uvx",
      "args": [
        "composer-mcp-server"
      ],
      "env": {
        "COMPOSER_API_KEY": "<insert-your-api-key-here>",
        "COMPOSER_SECRET_KEY": "<insert-your-api-secret-here>"
      }
    }
  }
}

Available tools

Once your LLM is connected to the Composer MCP Server, it will have access to the following tools:

• create_symphony - Define an automated strategy using Composer's system.
• backtest_symphony - Backtest a symphony that was created with create_symphony
• backtest_symphony_by_id - Backtest an existing symphony given its ID
• save_symphony - Save a symphony to the user's account
• update_saved_symphony - Update a saved symphony
• list_accounts - List all brokerage accounts available to the Composer user
• get_account_holdings - Get the holdings of a brokerage account
• get_aggregate_portfolio_stats - Get the aggregate portfolio statistics of a brokerage account
• get_aggregate_symphony_stats - Get stats for every symphony in a brokerage account
• get_symphony_daily_performance - Get daily performance for a specific symphony in a brokerage account
• get_portfolio_daily_performance - Get the daily performance for a brokerage account
• get_saved_symphony - Get the definition about an existing symphony given its ID.
• get_market_hours - Get market hours for the next week
• invest_in_symphony - Invest in a symphony for a specific account
• withdraw_from_symphony - Withdraw money from a symphony for a specific account
• cancel_invest_or_withdraw - Cancel an invest or withdraw request that has not been processed yet
• skip_automated_rebalance_for_symphony - Skip automated rebalance for a symphony in a specific account
• go_to_cash_for_symphony - Immediately sell all assets in a symphony
• liquidate_symphony - Immediately sell all assets in a symphony (or queue for market open if outside of market hours)
• preview_rebalance_for_user - Perform a dry run of rebalancing across all accounts to see what trades would be recommended
• preview_rebalance_for_symphony - Perform a dry run of rebalancing for a specific symphony to see what trades would be recommended
• rebalance_symphony_now - Rebalance a symphony NOW instead of waiting for the next automated rebalance
• execute_single_trade - Execute a single order for a specific symbol like you would in a traditional brokerage account
• cancel_single_trade - Cancel a request for a single trade that has not executed yet

Troubleshooting

Logs when running with Claude Desktop can be found at:

• Windows: %APPDATA%\Claude\logs\mcp-server-composer.log
• macOS: ~/Library/Logs/Claude/mcp-server-composer.log

MCP Composer: spawn uvx ENOENT

If you encounter the error "MCP Composer: spawn uvx ENOENT", confirm its absolute path by running this command in your terminal:

which uvx

Once you obtain the absolute path (e.g., /usr/local/bin/uvx), update your configuration to use that path (e.g., "command": "/usr/local/bin/uvx"). This ensures that the correct executable is referenced.