Building Zero-Dependency MCP Servers in Pure Python

Short summary

Anthropic's Model Context Protocol (MCP) enables AI assistants to access external tools, but the official SDK requires 47 transitive dependencies. This article walks through implementing a complete MCP server in pure Python using only the standard library (json, socket, asyncio), explaining JSON-RPC 2.0 transport over stdio and covering the three core capabilities: tools, resources, and prompts. Valuable for developers in sandboxed environments, security-conscious deployments, or learning the protocol architecture.

• •MCP is Anthropic's open standard protocol for connecting AI assistants to external data and tools
• •Official SDK has 47 dependencies; this tutorial implements MCP using only Python's standard library
• •Covers JSON-RPC 2.0 over stdio with full tool, resource, and prompt capabilities

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