MCP and function calling are often framed as competing approaches, but they operate at different layers. Function calling is how an LLM expresses intent by returning structured tool requests, while MCP (Model Context Protocol) standardizes how those requests are executed across tools and providers via a client-server
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What function calling and MCP actually doHow the architecture differs under the hoodThe vendor lock-in problem across OpenAI, Anthropic, Gemini, and LlamaWhen MCP is worth the overheadSecurity, credentials, and governing MCP at scaleChoosing function calling, MCP, or bothShip Faster with AISort: