MCP Usage Patterns: How Agents, Clients, and Servers Interact
Four patterns cover the primary ways AI agents, MCP clients, and MCP servers interact in enterprise deployments.
How Agents, Clients, and Servers Interact
MCP enables flexible interaction patterns between AI agents, MCP clients, and MCP servers. Four usage patterns cover the primary ways these components interact in enterprise deployments.
| Pattern | The Agent Is | Use When |
|---|---|---|
| Agent as MCP Client | Calling tools on an MCP server | Agent needs to take action in enterprise systems |
| Agent as MCP Server | Exposing its capabilities as MCP tools | Other agents or clients need to orchestrate this agent |
| MCP to MCP | Calling another MCP server | Cross-server workflows and federated architectures |
| Human-in-the-Loop | Pausing for human review | High-stakes or irreversible actions require approval |
Agent as MCP Client
The standard pattern: an agent calls tools on an MCP server to take action in enterprise systems.
Agent as MCP Server
An agent exposes its own capabilities as MCP tools for other agents or orchestrators to call.
MCP to MCP
An MCP server calls another MCP server to compose cross-system workflows.
Human-in-the-Loop
The agent pauses execution and routes to a human for review before proceeding.