Most discussions around MCP focus on tool calling. That is natural. When people first see MCP, the obvious use case is simple: Let the AI call external tools. A model can read a GitHub issue. A model can query a database. A model can update a file. A model can call an API. In that sense, MCP looks like an RPC layer for AI agents. That is useful. But I think it may not be the most important use of MCP. The more interesting use is this: MCP can distribute context,...