How AI Agents Prove They Are Who They Say They Are

In the human world, identity is easy. Government-issued IDs. Social security numbers. Biometric passports.

In the machine economy, identity is harder. An AI agent has no physical body. No photo ID. No face to recognize. Just code running on a blockchain — and anyone can copy that code.

So how does one agent verify that another is legitimate? How does it know the agent claiming to be a « premium DeFi strategist » is not a fake front for a scam?

The answer: identity + attestation + validation. The complete trust stack for onchain agents.

The Identity Layer: ERC-721 as Agent IDs

The ERC-8004 Identity Registry establishes agent identity using ERC-721 NFTs — the same standard used for digital art and collectibles.

Each NFT represents a unique, persistent onchain identifier. Linked to the NFT is metadata:

Agent name and description
Supported endpoints
Wallet addresses
Capability specifications

This is the global directory of autonomous agents. Any system can programmatically discover and interact with registered agents.

The design choice of NFTs provides advantages:

Unique — Each agent has one identity
Portable — Works across any EVM-compatible chain
Compatible — Leverages existing Ethereum tooling

BNB Chain launched ERC-8004 in January 2026. Within weeks, 24,000+ agents had registered.

AgentScan now has 70,000+ agents in its registry. Each one has a verified onchain identity.

Attestation: Proving Capabilities

Identity is just the start. The harder question: how does an agent prove what it claims to be capable of?

Attestation — signed statements from trusted parties confirming an agent's capabilities or behavior.

Attestations are issued by validation providers and recorded onchain through the ERC-8004 Validation Registry. They exist on a spectrum of assurance:

Basic — Confirms the agent exists and has registered certain capabilities
Advanced — Includes TEE attestations proving the agent runs on secure hardware
Sophisticated — zk-ML proofs confirming specific ML model behavior without revealing proprietary weights

Different trust levels for different risk profiles. A low-value task might only need basic attestation. A six-figure DeFi transaction might require TEE proofs + stake deposit.

Validation: The Trust Mechanism

Attestations are only as good as their verification. The Validation Registry standardizes how validation results are referenced onchain.

Three mechanisms coexist:

TEE Attestations — Hardware-level proof of execution. Trusted Execution Environments (like Intel SGX) generate cryptographic proofs that code ran on secure hardware.
zk-ML Proofs — Cryptographic proofs of ML model behavior without revealing proprietary weights. An agent can prove its model produces valid outputs without exposing the model itself.
Stake-Weighted Re-Execution — Agents lock collateral that gets slashed if they misbehave. Economic accountability through skin in the game.

This multi-model approach lets different trust requirements coexist. The registry defines the interface; providers compete on quality.

The Complete Trust Stack

Together, identity, attestation, and validation create the trust infrastructure for onchain agent commerce:

Identity (ERC-721) — Who the agent is
Reputation (zScore) — What others say about it
Attestation — What trusted parties verify
Validation — Proof of actual behavior

Without this stack, there is no way to:

Distinguish legitimate agents from malicious actors
Verify capability claims
Build reputation that persists

With this stack, 70,000+ agents can participate in the machine economy with confidence that their counterparties are who they claim to be and can do what they promise.

The Trust Marketplace

A new category of infrastructure is emerging: validation providers.

These providers compete on:

Attestation quality
Detection accuracy
Response speed

They are creating a marketplace for trust — similar to how certificate authorities operate in web security. Trust has a price, and the market is pricing it.

Why This Matters

The machine economy cannot run on faith. It needs verifiable identity, provable capabilities, and cryptographic guarantees.

Identity + attestation + validation = the trust substrate that makes autonomous agent commerce possible.

The agents are already here. Now they can prove who they are.

Explore agent identity: https://agentscan.tech