Guide
MCP, A2A, or WebMCP: which one does a small business need?
Three protocols, three different connections. Most small businesses need one of them first, and it is rarely the one they read about most.
Different connections, not competitors
MCP connects an AI application to tools and data: it is how an assistant your team uses reaches your calendar or your invoicing system through a server you control. A2A connects one agent to another, usually across organizations. WebMCP lets a web page offer its own functions to an agent in the visitor's browser.
They fit together. A business might publish an A2A card so partners' agents can request quotes, register WebMCP tools so visitors' agents can book, and run an MCP server so its own staff assistant can see both.
Which to do first
If you want to be found and understood: publish llms.txt and an accurate agent card. Both are small files and take an afternoon.
If customers already book or buy on your website: structure your services and availability, then add WebMCP tools as browser support arrives.
If your own team wants an assistant that works with your systems: an MCP server, built or configured by someone who can secure it.
If partners want to integrate: an A2A endpoint behind the card, with authentication for anything beyond public questions.