The Model Context Protocol (MCP) allows large language models like Claude to access external data sources, such as Neo4j databases, through a client-server architecture. The MCP server provides context, tools, and prompts to clients, enabling them to query the database, generate code, and visualize results. The protocol follows JSON-RPC 2.0 and supports different transport protocols, including HTTPS and STDIO. Security is a key concern, with features like user consent, data privacy access control, tool safety, and LLM sampling controls in place to prevent malicious code execution and ensure safe tool usage. Implementing an MCP server for a tool of your choice can be straightforward, and combining it with Claude's code generation and execution capabilities takes the interaction to the next level. The MCP enables large language models like Claude to access external data sources, providing a more comprehensive conversational experience.