MCP vs A2A — which protocol has the broader future?

Raw notes — thinking aloud on the two biggest interoperability pushes in the AI agent world: Anthropic’s MCP (Model Context Protocol) vs Google’s A2A (Agent-to-Agent). This is my personal lab notebook, where I try to map how these ecosystems might evolve.

Why these protocols matter

If agents are the next internet, then protocols like MCP and A2A are their TCP/IP. They define how apps, tools, and agents talk to each other. Whoever wins here could set the rules for collaboration across the next decade.

MCP — the open ecosystem play

MCP is open-source and broadly available. Anyone can build adapters, servers, or integrations. That makes it feel closer to Android or Next.js: fast-moving, messy at times, but growing through community scale. The bet is that openness plus early adoption turns MCP into a de facto standard, just like Kubernetes did in infrastructure.

A2A — the Workspace premium edge

A2A is narrower but focused: agents collaborating inside Google Workspace. Think Docs, Sheets, Meet, Drive all becoming agent-friendly. That’s powerful for enterprises already living in Workspace. But it’s also a bit like macOS/iOS: polished, reliable, but slower and more controlled. Great for premium users, less so for broad experimentation.

Other contenders

MCP and A2A aren’t alone. OpenAI has its own agent SDKs, LangChain pushes LCEL, and startups are launching interoperability layers weekly. But these two represent the clearest philosophical split: open community fabric vs controlled enterprise polish.

My prediction

In the next 2–4 years, I think MCP has the broader chance of domination. Its open-source nature and flexibility make it more likely to scale across startups, enterprises, and hobby projects. A2A will still hold a premium slice of the market — especially in enterprise collaboration — but risks getting stuck in the same loop as macOS where innovation feels gated by update cycles.

Closing thought

If AI agents are the next internet, MCP feels like TCP/IP — open, foundational, everywhere. A2A may carve out an Apple-like premium edge, but my bet is that MCP becomes the default language of agent communication.