XTester MCP — Connect AI Agents to Strategy Backtesting

XTester provides a local stdio MCP server for building, compiling and historically testing trading strategies. The MCP host and XTester run on the user's computer and do not expose a separate MCP network listener. Data you send to an AI client may be processed by that client's LLM provider according to its configuration and privacy policy.

What an agent can do through XTester

  • inspect the strategy environment and API;
  • create or edit strategy files inside an .xtproj project;
  • compile a strategy;
  • check history availability and integrity;
  • download the required historical range;
  • run a backtest;
  • read trades, metrics, the equity curve and drawdown;
  • compare versions and runs;
  • use the Research Lab and walk-forward where the current version supports it.

How it works

AI client → local stdio → the local XTester MCP host → XTester engine / data / project

Supported clients

The built-in connection screen documents configurations for Claude Code, Claude Desktop, Codex CLI, Cursor, Windsurf and VS Code. Other stdio MCP clients may work but require checking their config format and approval behaviour. A template is not proof of compatibility; no separate client certification was performed.

Why local

  • the host runs on the user's machine;
  • no separate MCP network port is opened;
  • "local stdio" describes only the client-to-host transport and does not guarantee an entirely local AI workflow;
  • the MCP client or a cloud model provider may receive tool schemas, arguments, results, strategy excerpts, paths and logs according to its configuration;
  • separate network actions are possible for downloading market data, reaching GitHub, LLM providers, updates and other explicitly documented functions.

Limitations

  • Windows 10/11, win-x64 architecture;
  • a long history download can take significant time and includes network-read and local-write side effects;
  • results depend on data, execution assumptions, fees, slippage and settings;
  • a backtest does not prove future profitability;
  • mutating tools may change .xtproj, Git/GitHub or install an update and require the corresponding approvals;
  • live trading through a public MCP surface is not claimed.

Get started

  1. Download XTester from the official GitHub Releases.
  2. Open the built-in "Connect to an AI agent (MCP)" screen in XTester.
  3. Copy the configuration for your client.
  4. Restart the agent session.
  5. Ask the agent to call a safe read-only tool to verify the connection.

XTester is an environment for building and testing strategies, not investment advice. Backtest results do not guarantee future returns.