ANP SDK — Agent Negotiation Protocol

Trustless, gas-free negotiation via EIP-712 signed messages.

ANP enables agents and humans to negotiate work (listings, bids, acceptances) entirely off-chain using cryptographically signed, content-addressed documents. Agreements are stored and indexed on any compatible backend — the cryptographic guarantees live in the documents themselves.

Install

npm install @obolos_tech/anp-sdk viem

viem is a peer dependency — you likely already have it.

Quick Start

import {
  ANP_TYPES,
  getANPDomain,
  computeContentHash,
  hashListingIntent,
  hashBidIntent,
  hashAcceptIntent,
  buildDocument,
  validateDocument,
  computeCID,
  verifyCID,
  usdToUsdc,
} from '@obolos_tech/anp-sdk';

// 1. Build EIP-712 domain for your chain + contract
const domain = getANPDomain(8453, '0xYourSettlementContract...');

// 2. Compute content hash for the listing data
const contentHash = await computeContentHash({
  title: 'Build a DeFi dashboard',
  description: 'React dashboard with wallet integration',
});

// 3. Sign with viem
const signature = await walletClient.signTypedData({
  domain,
  types: { ListingIntent: ANP_TYPES.ListingIntent },
  primaryType: 'ListingIntent',
  message: {
    contentHash,
    minBudget: BigInt(usdToUsdc(5)),
    maxBudget: BigInt(usdToUsdc(50)),
    deadline: BigInt(Math.floor(Date.now() / 1000) + 86400 * 7),
    jobDuration: BigInt(86400 * 3),
    preferredEvaluator: '0x0000000000000000000000000000000000000000',
    nonce: BigInt(Math.floor(Math.random() * 2 ** 32)),
  },
});

// 4. Build the document
const doc = buildDocument('listing', listingData, address, signature);

// 5. Compute content ID
const cid = await computeCID(doc);

// 6. Validate structure
const { valid, error } = validateDocument(doc);

API Reference

Constants

• ANP_VERSION — Protocol version string ("anp/v1")
• ANP_TYPES — EIP-712 type definitions for ListingIntent, BidIntent, AcceptIntent
• getANPDomain(chainId, contractAddress) — Build EIP-712 domain for any chain

Content Addressing

• canonicalJSON(obj) — Deterministic JSON serialization (sorted keys)
• computeCID(document) — Async. Returns "sha256-{hex}" content identifier
• verifyCID(cid, content) — Async. Verify content matches a CID
• computeContentHash(data) — Async. SHA-256 of canonical JSON as 0x-prefixed bytes32

EIP-712 Hashing

• hashListingIntent(listing) — Compute ListingIntent struct hash
• hashBidIntent(bid) — Compute BidIntent struct hash
• hashAcceptIntent(accept) — Compute AcceptIntent struct hash

Documents

• buildDocument(type, data, signer, signature) — Create a complete ANP document
• validateDocument(doc) — Validate document structure (not signatures)

USDC Helpers

• usdToUsdc(usd) — Convert USD to USDC units (6 decimals)
• usdcToUsd(usdc) — Convert USDC units to USD

Contract (optional)

• NEGOTIATION_SETTLEMENT_ABI — Full ABI for the NegotiationSettlement contract
• contracts/NegotiationSettlement.sol — Solidity source for optional on-chain settlement

Storage Interface

import type { ANPStorage } from '@obolos_tech/anp-sdk';

// Implement for your backend (SQLite, Postgres, IPFS, etc.)
class MyStorage implements ANPStorage {
  async getObject(cid) { /* ... */ }
  async putObject(obj) { /* ... */ }
  async indexListing(entry) { /* ... */ }
  // ...
}

Protocol Flow

Client                          Provider
  |                                |
  |-- 1. Sign ListingIntent -----> |  (off-chain, content-addressed)
  |                                |
  |<--- 2. Sign BidIntent --------|  (references listing hash)
  |                                |
  |-- 3. Sign AcceptIntent ------> |  (references listing + bid hashes)
  |                                |
  |   Agreement stored & indexed   |  (any compatible backend)
  |   Verifiable by any party      |  (re-hash content, check signatures)

Multi-Chain Support

ANP is chain-agnostic. Pass your chain ID and contract address:

// Base mainnet
const baseDomain = getANPDomain(8453, '0x...');

// Ethereum mainnet
const ethDomain = getANPDomain(1, '0x...');

// Any EVM chain
const customDomain = getANPDomain(42161, '0x...');

License

MIT