Agents And Tool Use medium
Your company runs five agent hosts (an IDE assistant, a chat app, a CI bot, and two internal tools). Each has its own bespoke integration code for the same ten internal systems. You want to stop duplicating that code. What role does the Model Context Protocol (MCP) play?
- A A protocol: wrap each internal system once as an MCP server exposing tools and resources any compliant host can use.
- B A shared model: route all five hosts through a single MCP model that has been fine-tuned to know the ten internal systems.
- C An orchestration framework that replaces each host's planning loop with a centralized MCP agent that makes all decisions.
- D A vector store standard that indexes the ten systems' documentation so each host's model can retrieve API details on demand.
Answer: A. A protocol: wrap each internal system once as an MCP server exposing tools and resources any compliant host can use.
MCP is a **protocol**, not a model or a planner. It standardizes how tools and resources are exposed to a host, so each system is integrated once and reused by every compliant host. Option B is the common misconception that MCP is a model. The tradeoff is running and securing extra server processes. For a single host with two integrations, direct function definitions may be simpler.
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