MCP Solves Tool Discovery for LLMs
Coding agents like Claude Code and OpenAI Codex don’t struggle with terminals; they struggle to discover tools that exist. If a command isn’t in the model’s training set or post-training hill climbing, they won’t even know to try it. MCP fixes discovery by giving models a live, machine-readable catalog of tools with names, descriptions, input schemas, and example calls. MCP gives the models tokens.

Unix pipes and man pages gave humans both composition and discovery. In agentic systems, LLMs provide composition and MCP gives LLMs discoverability + affordances.
MCP is the universal plugin interface, but LLM behavior is
fundamentally driven by, and constrained by, input tokens. MCP offers something
that CLIs ambiently available in $PATH
(or training data) never could: a
built-in mechanism to automatically prompt the model so it doesn’t have to guess
or hunt for tools.
The CLI your developer productivity team built to accelerate human developers is illegible to a coding agent. Agent-first development means prompting the model from the start — and MCP bakes that into tool authorship.