How does MCP compare to OpenAI function calling and Anthropic tool use?
Function calling and tool use are provider-specific APIs that let an LLM invoke tools. MCP (Model Context Protocol) is a shared open protocol that lets any MCP-speaking client — Claude Desktop, Cursor, ChatGPT Desktop, Zed, the OpenAI Agents SDK — invoke tools from any MCP server, regardless of who wrote them. In practice you use both: MCP for portability across agents; function calling / tool use for provider-native performance and features. See /vs/mcp-vs-rest-api.
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Framework dimensions
Call this framework and its tools from your own agent via the Model Context Protocol (MCP) server. Works with Claude Desktop, Cursor, Zed, Continue, and the OpenAI Agents SDK.
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