{
  "slug": "erc-8004-trustless-agents",
  "title": "ERC-8004 Trustless Agents: Identity, Reputation and Validation Registries",
  "description": "ERC-8004 Trustless Agents is a Draft Ethereum standard for discovering agents across organisations through three registries (identity, reputation, validation); what it specifies, what it cannot prove, and where it sits next to MCP, A2A and Web Bot Auth.",
  "category": "Guide",
  "tags": [
    "erc-8004",
    "agent-identity",
    "reputation",
    "ethereum",
    "x402",
    "agents",
    "protocols"
  ],
  "updated": "2026-10-13",
  "premium": false,
  "rights": {
    "access": "free",
    "license": "https://changegamer.ai/license.xml",
    "pricing": "https://changegamer.ai/api/pricing.json",
    "payment": "https://changegamer.ai/api/payment.json"
  },
  "canonical": "https://changegamer.ai/resources/erc-8004-trustless-agents",
  "markdown": "https://changegamer.ai/resources/erc-8004-trustless-agents.md",
  "outline": [
    {
      "depth": 2,
      "text": "Key facts",
      "anchor": "key-facts"
    },
    {
      "depth": 2,
      "text": "What do the three registries do?",
      "anchor": "what-do-the-three-registries-do"
    },
    {
      "depth": 2,
      "text": "What are its limits?",
      "anchor": "what-are-its-limits"
    },
    {
      "depth": 2,
      "text": "How does it relate to MCP, A2A and Web Bot Auth?",
      "anchor": "how-does-it-relate-to-mcp-a2a-and-web-bot-auth"
    },
    {
      "depth": 2,
      "text": "Sources",
      "anchor": "sources"
    }
  ],
  "related": [
    {
      "slug": "a2a-protocol",
      "title": "A2A Protocol (Agent2Agent): Agent Card, Operations, Task States, Bindings",
      "description": "Wire-level reference for the A2A (Agent2Agent) protocol v1.0: the Agent Card at /.well-known/agent-card.json, the 11 operations, the 8 task states, three protocol bindings, security schemes, version negotiation, and what changed from v0.3.",
      "url": "https://changegamer.ai/resources/a2a-protocol"
    },
    {
      "slug": "a2ui-protocol",
      "title": "A2UI: Google's Declarative Agent-to-UI Protocol (vs AG-UI, MCP Apps)",
      "description": "What A2UI is: the open, Apache-2.0 standard in which agents send declarative JSON describing the intent of a UI and the client renders it from a catalog it controls; the four v0.9 message types, transport requirements, renderer status, and how A2UI relates to AG-UI, A2A and MCP Apps.",
      "url": "https://changegamer.ai/resources/a2ui-protocol"
    },
    {
      "slug": "agent-spend-controls",
      "title": "Agent Spend Controls: Budget Caps, Approval Gates, and Kill Switches",
      "description": "How to bound what an autonomous agent can spend — per-transaction caps, session/daily ceilings, human-in-the-loop approval thresholds, and kill switches — across the three layers agents now spend money on: LLM API cost, on-chain wallet payments, and card-network agent tokens.",
      "url": "https://changegamer.ai/resources/agent-spend-controls"
    },
    {
      "slug": "agent-wallets-x402",
      "title": "Agent Wallets: Paying Per Run with x402",
      "description": "Buyer-side guide to giving an AI agent a wallet: how the x402 payment loop works, the client libraries that automate it, spend controls, and what 20,000+ Apify Actors on x402 mean for agent tool budgets.",
      "url": "https://changegamer.ai/resources/agent-wallets-x402"
    }
  ],
  "furtherReading": [
    {
      "slug": "acp-vs-ap2-vs-x402",
      "title": "ACP vs. AP2 vs. x402: Which Agent Payment Rail Should You Implement?",
      "description": "A decision framework for choosing between ACP, AP2, and x402 (plus the self-hosted 402 gate) — sorted by who your buyer actually is, what you are selling, and what is live versus waitlisted as of July 2026.",
      "url": "https://changegamer.ai/articles/acp-vs-ap2-vs-x402"
    },
    {
      "slug": "agent-checkout-vs-human-checkout",
      "title": "Agent Checkout vs. Human Checkout: Why Your Payment Flow Fails Machine Buyers",
      "description": "Why checkout built for a person watching a screen is unusable by an AI agent, and what a checkout flow that actually completes for a machine buyer looks like — 402 + API key versus native x402.",
      "url": "https://changegamer.ai/articles/agent-checkout-vs-human-checkout"
    }
  ],
  "body": "ERC-8004 Trustless Agents is an Ethereum standard proposal for discovering agents and establishing trust in them across organisational boundaries, using three on-chain registries. Decision rule: use it when you need a portable, cross-organisation agent identity and reputation record; it does not make an agent safe.\n\n## Key facts\n\n- Status: Draft (Standards Track: ERC), per the EIP page on 2026-10-13. Drafts can change.\n- Created 2025-08-13. Requires EIP-155, EIP-712, EIP-721 and EIP-1271.\n- Three registries: identity, reputation, validation. The spec expects per-chain singleton deployments.\n- Source: https://eips.ethereum.org/EIPS/eip-8004\n\n## What do the three registries do?\n\n- Identity Registry: ERC-721 with the URIStorage extension. The token owner owns the agent. Key functions: `register`, `setAgentURI` (the URI resolves to a registration file listing endpoints such as MCP, A2A, ENS or DID), `setMetadata`, and `setAgentWallet` (requires an EIP-712 or ERC-1271 signature from the new wallet; the wallet is cleared on transfer).\n- Reputation Registry: `giveFeedback` (signed fixed-point value plus optional tags), `revokeFeedback`, `appendResponse` (anyone may append), and `getSummary`. The agent owner cannot submit feedback for its own agent (nor can its approved operators).\n- Validation Registry: `validationRequest` by the agent owner or operator and `validationResponse` by the named validator, with a response from 0 to 100 (0 failed, 100 passed, values between allowed). Validator incentives and slashing are outside the registry.\n\n## What are its limits?\n\n- Sybil attacks: the spec says fake agents can inflate reputation. `getSummary` requires a non-empty list of client addresses, so you choose whose feedback to trust.\n- Immutability: on-chain pointers and hashes cannot be deleted.\n- The registry ties a registration file to an on-chain agent, but the spec states it cannot cryptographically show that advertised capabilities work or are non-malicious.\n- The `supportedTrust` field is optional; if absent or empty, the registration is for discovery only, not trust.\n\n## How does it relate to MCP, A2A and Web Bot Auth?\n\nBy layer. MCP and A2A are communication protocols (see /resources/mcp-vs-a2a and /resources/a2a-protocol); the EIP motivates ERC-8004 by saying they do not inherently cover agent discovery and trust, and its registration file can point to an MCP or A2A endpoint. Web Bot Auth (/resources/web-bot-auth) is a different layer: HTTP Message Signatures that prove to an origin server who is making a request. The EIP treats payments as orthogonal and shows x402 as an optional proof-of-payment feedback field and a boolean `x402Support` flag in the registration file (see /resources/agent-wallets-x402).\n\nSee also: /resources/agent-identity-authentication, /resources/agent-wallets-x402, /resources/web-bot-auth\n\n## Sources\n\n- ERC-8004: Trustless Agents (Draft), fetched 2026-10-13: https://eips.ethereum.org/EIPS/eip-8004",
  "sources": []
}