Agents & tools
An open standard that lets AI agents built by different companies find each other, hand over tasks and share results.
Formal
An open protocol in which each AI agent publishes a card describing what it can do and how to reach it, and other agents send it tasks over the web, follow their progress and receive results, without seeing how the agent works inside.
In plain English
Like a shared job board for freelancers - each posts what they are good at, and others can hire them for a piece of work without caring how they do it.
In practice
A travel coordinator at a ministry uses a trip-planning agent that finds a travel agency's booking agent through its card, sends the dates and budget over A2A and gets back three priced options an hour later.
Why it matters
It could let agents from different vendors work together, but every agent you accept work from is a stranger whose answers need the same doubt as any outside input.