[OkGoDoIt]

Part of the reason AI agents and MCP work is because AI can programmatically at runtime determine what plug-ins to use. Without the AI part, how does the host app know when to call a MCP server function?

[baq]

Same way it would call any other api: exactly when it was programmed to.

[notatoad]

same as any other api function call in an app - because an app developer programmed it to call that function.

[brabel]

That only works for the MCPs your app knows about, which is not that great. The usefulness of a plugin system like MCP is that an app can automatically use it. But MCPs are literally just a function, with some metadata about what it does and how to invoke it. The only thing generic enough to figure out how to use a function given only this metadata seems to be an LLM. And not even all of them, only some support “toll calling “.