Python execute

# py_execute_mcp

MCP stdio server that executes Python code inside Pyodide (WASM) using Bun as the runtime and bundler.

Prerequisites

• Bun v1.2 or newer (install script: powershell -Command "iwr https://bun.sh/install.ps1 -UseBasicParsing | iex")

Install dependencies

bun install

Run the server (development)

bun run src/index.ts

Expose bun run src/index.ts as an MCP stdio endpoint in Claude Desktop, Cherry Studio, or any compliant client.

Package as a single executable

bun build src/index.ts --compile --outfile mcp-python

Optional: Offline Pyodide

Download a Pyodide distribution and set PYODIDE_INDEX_URL before launching:

set PYODIDE_INDEX_URL=file:///absolute/path/to/pyodide/full/
./mcp-python

Minimum example request

# /// script
# dependencies = ['pydash']
# ///
import sys
print(sys.version)
print(sum([1, 2, 3]))
"done"

python_execute will stream stdout/stderr and return the expression result under __RESULT__ when present.