What is an MCP Client?

In the Model Context Protocol architecture, the client and server are cleanly separated: the client (living inside the AI application) handles the connection, capability negotiation, and request/response lifecycle, while the server exposes a specific set of tools or data sources without needing to know anything about the model or application consuming it. A single client can maintain connections to multiple servers simultaneously — a local file-system server, a remote CRM integration, a database server — presenting the agent with a unified, dynamically discovered toolset rather than each integration needing custom, hardcoded glue code. Because the client mediates every tool call, it's also the natural enforcement point for permissions and auditing: it can scope which servers and tools are available for a given session, log every call and its result, and reject calls that fall outside the current task's authorized scope. This makes the client-server split in MCP as much a security architecture decision as a technical convenience — it lets an organization add or remove integrations without touching the agent's core logic, and centralizes control over what an agent can actually reach.