---
title: "MCP is a toolbox. A2A is a coworker."
date: 2026-07-14
description: "MCP and A2A get lumped together, but they solve different problems."
---

Something I've been chewing on: [MCP](https://modelcontextprotocol.io/specification) and A2A get lumped together, but they solve different problems.

MCP exposes tools, resources, and prompts to an AI client. It gives an agent capabilities like `search_notes`, `read_note`, or `create_note_pr`.

A2A is also a protocol, but designed for one agent to delegate work to another. Instead of calling a low-level tool, the caller asks a publishing agent to "turn this idea into a note and open a PR." The publishing agent owns the workflow and decides how to do it.

The mental model I keep landing on:

- **MCP is a toolbox.**
- **A2A is a coworker.**

They're complementary. An A2A agent can use MCP tools internally.

Example flow: ChatGPT → A2A publishing agent → MCP tools (GitHub, Vercel, and so on).

MCP is the plumbing. A2A is the collaboration layer.