PolyMCP – Expose Python/TS functions as MCP tools easily

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PolyMCP – Expose Python/TS functions as MCP tools easily

I made PolyMCP so I could quickly turn normal functions (Python or TypeScript) into MCP tools without much extra work. Python example: from polymcp.polymcp_toolkit import expose_tools def greet(name: str) -> str: """Say hello.""" return f"Hello, {name}!" def add(a: int, b: int) -> int: """Add two numbers.""" return a + b app = expose_tools([greet, add], title="My MCP Tools") Run with: uvicorn server:app --reload MCP endpoints appear at /mcp/list_tools and /mcp/invoke/. TypeScript example: import { z } from 'zod'; import { tool, exposeTools } from 'polymcp'; const uppercaseTool = tool({ name: 'uppercase', description: 'Convert text to uppercase', inputSchema: z.object({ text: z.string() }), function: async ({ text }) => text.toUpperCase(), }); const app = exposeTools([uppercaseTool], { title: "Text Tools" }); app.listen(3000); Business example (Python): import pandas as pd from polymcp.polymcp_toolkit import expose_tools def calculate_commissions(sales_data: list[dict]): df = pd.DataFrame(sales_data) df["commission"] = df["sales_amount"] * 0.05 return df.to_dict(orient="records") app = expose_tools([calculate_commissions], title="Business Tools") What you get: • Reuse existing code with minimal changes • Compatible with MCP clients (Claude Desktop, agents, Ollama, etc.) • HTTP and stdio and Wasm support • Automatic validation • Basic production features (budgets, retries, redaction, logs) • Inspector: polymcp inspector for testing/monitoring Install: • Python: pip install polymcp • TypeScript: clone repo → cd polymcp-ts → npm install → npm run build Repo: https://github.com/poly-mcp/Polymcp Curious what kind of function people would expose first if it was this simple. Feedback welcome.