agent-proofchain

Tamper-evident action journal for AI agents using hash-linked entries and signed run manifests.

Features

• Deterministic canonical JSON serialization
• SHA-256 hash-linked journal entries (prevHash + entry hash)
• Strong runtime validation with built-in assertion guards
• Ed25519 manifest signing and verification
• Replay verification for full chain integrity and policy consistency
• Action adapters for tool calls and blockchain transactions

Install

npm install agent-proofchain

Quickstart

import { createJournal, createEd25519KeyPair, signManifest, verifyManifestSignature } from "agent-proofchain";
import { createToolCallAction } from "agent-proofchain/adapters/tool-call";

const journal = createJournal({
  policySnapshot: {
    id: "policy-1",
    version: "2026-02-28",
    capturedAt: "2026-02-28T00:00:00.000Z",
    rules: { allowTools: ["search"] }
  }
});

journal.append(
  createToolCallAction({
    toolName: "search",
    args: { q: "agent-proofchain" },
    success: true
  })
);

const verifyResult = journal.verify({ requireConsistentPolicyHash: true });
if (!verifyResult.ok) throw new Error(verifyResult.error);

const keys = createEd25519KeyPair();
const manifest = signManifest(
  {
    runId: "run-123",
    agentId: "agent-alpha",
    startedAt: "2026-02-28T12:00:00.000Z",
    journalHash: journal.journalHash()!
  },
  keys.secretKey,
  keys.publicKey
);

console.log("manifest valid:", verifyManifestSignature(manifest));

Verification Example

import { createJournal, replayVerify } from "agent-proofchain";

const journal = createJournal();
// append entries...

const exported = journal.export();
const replay = replayVerify(exported.entries, {
  requireConsistentPolicyHash: true
});

if (!replay.ok) {
  console.error("tamper detected at index", replay.invalidIndex, replay.error);
}

Blockchain Adapter Example

import { createJournal } from "agent-proofchain";
import { createBlockchainTxAction } from "agent-proofchain/adapters/blockchain-tx";

const journal = createJournal();
journal.append(
  createBlockchainTxAction({
    chainId: 1,
    txHash: "0x123...",
    from: "0xfrom",
    to: "0xto",
    value: "1000000000000000000",
    status: "confirmed"
  })
);

Development

npm install
npm run build
npm run test
npm run lint
npm run typecheck

License

MIT