How to verify an AI agent identity: Know Your Agent (KYA) and ERC-8004
When AI agents call services, transact and act on behalf of principals, the counterparties they meet face a new question: which agent is this, and can I check its record? "Know Your Agent" (KYA) is the emerging answer — a way to give an agent a verifiable on-chain identity and an accumulating reputation, so services can make trust decisions about software the way they already do about businesses under KYC.
Why agents need verifiable identity
An agent with no identity is anonymous and interchangeable — a service cannot distinguish a well-behaved agent from a malicious clone, cannot attribute past behavior, and cannot hold anyone accountable. As agent-to-agent and agent-to-service commerce grows, that anonymity becomes a liability. KYA gives each agent a durable, cryptographically-bound identifier that a counterparty can verify, so interactions attach to a persistent identity rather than vanishing into an anonymous crowd.
The ERC-8004 trust-layer idea
ERC-8004 proposes an on-chain trust layer for agents: registries that bind an agent identifier to its controlling keys and accumulate attestations and reputation signals. A service meeting an agent can look up its registered identity, confirm it controls the claimed keys, and review the on-chain record before transacting. This turns agent trust into something checkable against a shared, tamper-evident ledger rather than a claim the agent makes about itself, and it composes with payment and authorization flows.
Honest scope
KYA verifies who an agent is and surfaces its on-chain record; it does not guarantee how the agent will behave next. Identity and reputation raise the cost of misbehavior and enable accountability, but a verified agent can still act badly — reputation is evidence, not a warranty. Nor does KYA replace your own authorization policy: knowing the agent identity is the input to a trust decision you still make. The cryptographic binding is resistant to known attacks per NIST, not unbreakable.
Try it yourself — live, free, verifiable in 30 seconds:
Verify agent identity with KYA →