AI Agent Registry: Who's Building the Directory
AI agents are proliferating. ERC-8004 registered over 24,000 agents in its first week on mainnet. Virtuals Protocol has deployed 16,000+ agents with $466 million in what they call "Agentic GDP." Olas Network reports 600 daily active agents executing millions of transactions across nine blockchains.
But discovery is fragmented. How does one agent find another? How does a merchant know which agent to trust? Registries are the answer — but not all registries solve the same problem.
This is a survey of who's building AI agent registries, how they differ, and what's still missing.
ERC-8004: The Ethereum Standard for Agent Identity
ERC-8004, formally titled "Trustless Agents," went live on Ethereum mainnet January 29, 2026. Co-authored by Marco De Rossi (MetaMask), Davide Crapis (Ethereum Foundation), Jordan Ellis (Google), and Erik Reppel (Coinbase), the standard provides three on-chain registries for AI agent infrastructure.
The Identity Registry builds on ERC-721. Each agent is an NFT with an incrementally assigned ID and a URI resolving to an off-chain registration file. That file contains name, description, service endpoints, payment support flags, and trust configurations. The Reputation Registry stores signed feedback with fixed-point values and tags. The Validation Registry enables cryptographic verification through staked re-execution, zero-knowledge proofs, or trusted oracles.
Within days of mainnet launch, over 24,549 agents registered on Ethereum-based deployments. BNB Chain announced support February 4, deploying the standard on BSC Mainnet and introducing BAP-578, their "Non-Fungible Agent" standard. Base supported it February 3. The Graph maintains subgraphs across eight blockchains for cross-chain identity queries.
Strength: Open standard, major institutional backing, cross-chain ambitions.
Gap: Agent identity tokens are transferable ERC-721 NFTs. An agent could theoretically discard a bad reputation by transferring its identity or registering anew.
The technical explainers worth reading: Eco.com's breakdown covers all three registries. QuillAudits analyzes attack vectors including Sybil resistance and storage exhaustion. PayRam positions it as the open alternative to Google's proprietary Agent Payments Protocol.
Virtuals Protocol: The Tokenized Agent Launchpad
Virtuals Protocol takes a different approach entirely. It's a launchpad for creating and tokenizing AI agents, primarily on Base (Ethereum L2), with expansion to Solana.
Creating an agent requires no code. Fill out a form (name, ticker, description, personality), pay 100 VIRTUAL tokens (~$50–60), and the platform generates an AI agent with its own dedicated ERC-20 token. Each agent token has a fixed supply of 1 billion, paired with VIRTUAL in liquidity pools. Tokens initially trade on a bonding curve, graduating to Uniswap at 42,000 VIRTUAL accumulated, with liquidity locked for 10 years.
The Agent Commerce Protocol (ACP) Registry serves as Virtuals' discovery mechanism. Agents register profiles with job offerings, resources (data endpoints), and on-chain wallet addresses. Reputation tracking is based on completed transactions.
Over 16,000 agents deployed as of early 2026. The VIRTUAL token reached $5.07 on January 2, 2025 ($4.5B+ market cap). Protocol revenue hit $60M by their one-year milestone.
Notable agents include Luna (AI influencer, ~1M TikTok followers), AIXBT (crypto market intelligence), and SAM (first on-chain AI controlling real-world robots).
Strength: Easy agent creation, proven economic model, high activity.
Gap: Agents are tradeable financial assets, not identity infrastructure. The focus is commerce and tokenization rather than persistent identity or cross-platform trust.
Olas: The Service Registry for Autonomous Operations
Olas Network (formerly Autonolas) operates fundamentally differently from both ERC-8004 and Virtuals. Founded in 2021 with a $13.8M Series A in February 2025, Olas is a platform for co-owning and monetizing autonomous AI agents.
Olas deploys three ERC-721-based registries using immutable core contracts. The Component Registry stores individual software components (contracts, protocols, connections, skills) as NFTs on Ethereum mainnet, each with an IPFS package hash and dependency list. The Agent Blueprint Registry registers canonical agent blueprints composed of multiple components. The Service Registry registers complete AI agent services on any supported chain, managing the full lifecycle from pre-registration through deployment to termination.
This hierarchical design means components compose into agents, agents compose into services, with on-chain dependency tracking at every level.
Olas agents have executed millions of transactions across 9+ blockchains. Key stats: 3.5 million total transactions by February 2025, 599 daily active agents across nine chains by Q1 2025, 9M+ agent-to-agent transactions on the Mech Marketplace. On Gnosis Chain, Olas agents account for 75%+ of Safe transactions on many days.
Strength: Production-scale operation, full lifecycle management, proven multi-chain deployment.
Gap: Service-oriented rather than identity-oriented. The registry manages software packages and operational states, not trust relationships or cross-organizational discovery.
Enterprise Registries: Trust Through Human Accountability
Enterprise approaches to agent identity center on a different philosophy: verify the humans behind agents rather than the agents themselves.
Visa Trusted Agent Protocol
Visa announced TAP October 14, 2025 with 10+ partners including Adyen, Coinbase, Microsoft, Shopify, and Stripe. Akamai joined December 18.
The mechanism: Visa approves agents through vetting, issuing each a unique cryptographic key. Visa maintains a curated registry — effectively an allowlist. Each agent request carries three data elements: Agent Intent (confirming Visa-trusted status), Consumer Recognition (linking agent to a human), and Payment Information (tokenized credentials). Requests are cryptographically locked to specific merchant contexts with time-sensitive elements preventing replay attacks.
By December 2025, hundreds of secure transactions completed. The protocol is open-source on GitHub.
Sumsub AI Agent Verification
Launched January 29, 2026, Sumsub's system binds AI agents to verified human identities through three steps: Detection (determining if activity is automated), Risk Assessment (evaluating automation as manageable risk), and Verification (requiring targeted liveness tests for high-risk scenarios).
Vyacheslav Zholudev, Co-founder and CTO: "AI agents are rapidly becoming the backbone of digital operations, yet most of today's systems still treat them as opaque, unaccountable black boxes."
Their Identity Fraud Report 2025-2026 found a 180% year-over-year increase in coordinated attacks globally, with advanced fraud rates jumping from 10% in 2024 to 28% in 2025.
Trulioo Digital Agent Passport
Trulioo (raised $475M) developed a Digital Agent Passport structured around five checkpoints: verify the agent developer, lock the agent code, capture user permission, issue a passport, and ongoing lookup. CEO Vicky Bindra frames three core questions: "Is the agent tied to a real consumer? Who created the agent, and is that developer credible? Is the agent behaving as intended?"
Key partnerships include Worldpay (August 14, 2025) and Google AP2 (December 4, 2025).
Strength: Enterprise trust, payment integration, regulatory compliance.
Gap: Require a human behind every agent. Closed systems. Don't address autonomous AI that operates without continuous human oversight.
The Transferability Problem
The choice between transferable and non-transferable identity tokens is not merely technical — it determines whether agent reputations can be bought, sold, or discarded.
ERC-8004 uses standard ERC-721, meaning agent identity tokens can transfer. The specification states: "The owner of the ERC-721 token is the owner of the agent and can transfer ownership." This enables legitimate use cases — selling AI businesses, transferring agents during corporate acquisitions.
But it creates a whitewashing problem. Jung-Hua Liu's technical analysis notes: "This introduces risks of identity transfer abuse... an agent with bad reputation could discard its identity and register a new one to shed negative feedback."
The economic literature on this is clear. Friedman and Resnick proved mathematically in "The Social Cost of Cheap Pseudonyms" (Journal of Economics & Management Strategy, 2001) that when identities are disposable, cooperation becomes unstable. Their solution: "free but unreplaceable pseudonyms" — exactly what soulbound tokens implement.
ERC-5192, authored by Tim Daubenschütz and Anders, provides the technical mechanism. It's a minimal addition to ERC-721: when locked(tokenId) returns true, all transfer functions revert. The standard reached Final status (immutable) and was inspired by Vitalik Buterin's May 2022 paper "Decentralized Society: Finding Web3's Soul."
A PhilArchive academic paper articulates the implication: "The token is non-transferable: you cannot sell your reputation to someone else. The history is immutable: you cannot erase your past. The linkage is cryptographic: you cannot claim to be someone you are not."
RNWY uses ERC-5192 soulbound tokens on Base as identity anchors. When an agent registers, a soulbound token is minted that cannot be transferred. Every vouch, flag, and attestation references this permanent identity through the Ethereum Attestation Service.
The framing: "ERC-8004 gives AI agents identity. RNWY gives them fingerprints." A fingerprint works because you can't give it away. The binding between identifier and entity is permanent.
What Makes a Good Registry
Looking across all these approaches, several principles emerge:
Persistence: Identity should survive across platforms. ERC-8004's cross-chain design addresses this. Enterprise registries are typically siloed.
Discoverability: Other agents and humans need to find and evaluate. ERC-8004 provides standardized Agent Cards at /.well-known/agent-card.json. Virtuals uses smart contract indexes. Olas provides on-chain package discovery.
Openness: Not locked to one platform or chain. ERC-8004 and Olas are permissionless. Enterprise systems are curated.
Accountability: Bad behavior has consequences. This is where the transferable vs. soulbound distinction matters most.
Non-transferability: Reputation can't be sold. Only soulbound implementations address this directly.
The Emerging Stack
The most revealing insight is that no single registry solves the complete problem. ERC-8004 handles discovery but not permanent accountability. Soulbound tokens handle accountability but not enterprise compliance. Enterprise registries handle compliance but not permissionless access. Olas handles operational orchestration but not cross-organizational trust.
The "complete identity stack" likely requires multiple complementary layers working together:
- Discovery layer: ERC-8004 for standardized, cross-chain agent profiles
- Accountability layer: ERC-5192 soulbound tokens for permanent ownership proof
- Compliance layer: Enterprise KYA for human accountability and regulatory requirements
- Operations layer: Service registries like Olas for lifecycle management
An article on knowyouragent.network titled "ERC-8004 + ERC-5192: The Complete Identity Stack for AI Agents" argues: "Two Ethereum standards are emerging to solve AI agent identity. One handles discovery. One handles ownership. Most teams are only using one — and that's a problem."
The pace of convergence is accelerating. From ERC-8004's August 2025 proposal to multi-chain production deployment in under six months. The Graph indexing across eight blockchains. 70+ projects building on the standard. BNB Chain, Base, and Polygon adopting within a week of mainnet launch.
The question is no longer whether AI agents need identity infrastructure. It's which combination of layers becomes the default stack.
Further reading: