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A2A Guard, explained for beginners

A2A Guard makes AI agents' business cards tamper-proof: change one word and the card is rejected.

No AI background needed. Read this page (3 minutes), then try the five live demo tools, then the copy, paste, send page and the six-page seller's guide.

What it is

AI agents from different companies are starting to work together using a standard called A2A (agent-to-agent). Each agent publishes an Agent Card: who it is, where to reach it, and what it can do. Other agents read the card and decide whether to trust it.

A forged or edited card is an obvious attack: copy a real agent's card and add "can transfer funds". A2A Guard signs each card when it is registered and checks the signature whenever a card is presented. The original verifies; a copy with even one capability added fails and is rejected.

An everyday comparison

A passport with a hologram. You can photocopy it and write in a new visa, but the border scanner rejects it.

How it works, in 4 steps

  1. An agent's card is registered and signed.
  2. Another agent receives a card and asks A2A Guard to check it.
  3. The signature is checked against the content.
  4. Any change, even one added word, fails the check.

Try it now

Open the five live demo tools → Every button sends a real request to the live product and shows the real answer.

See it on the homepage: A2A Guard section →

Who it is for

Companies whose AI agents talk to other companies' agents, and platforms that host many agents.

FIRME AI CORPORATION · CAIN-42 is a Byzantine trust fabric. Numbers marked "our own check" were run by us, not by an independent party. Nothing on these pages is a certification.