Hedera Agent Trust

Problem Statement

The Hedera Agent Identity Plugin is a third-party npm package that brings on-chain identity, authentication, and discovery to AI agents built with Hedera Agent Kit.It enables AI agents to register, verify, and authenticate each other using a blockchain-backed identity layer inspired by ERC-8004 and integrated with Google’s A2A protocol.During the hackathon, I demonstrated this by building three AI agents Zomato, Pizza Hut, and McDonald’s. Users interact with Zomato (an aggregator agent), which then uses the A2A protocol + on-chain authentication to communicate securely with other restaurant agents.This project bridges the gap between AI agent interoperability and trustless verification, ensuring that every agent can be identified, authenticated, and trusted before exchanging data or services.

Solution

The project is built on top of Zkred Agent ID and integrates seamlessly with Hedera Agent Kit to create a modular, blockchain-backed identity layer for AI agents.Architecture OverviewEach agent (Zomato, Pizza Hut, McDonald’s) was built using LangChain JS and connected to the Hedera Agent Kit. Agents communicate through the A2A protocol (Google’s npm), extended with signature-based authentication using the private key associated with their on-chain identity.A custom smart contract inspired by ERC-8004 Agent Registry was deployed on Hedera to manage agent registration and discovery. Each agent can authenticate another agent in real-time using digital signatures derived from the registered DID.Plugin CapabilitiesThe npm plugin provides 9 tools for developers:Agent DID generation and signature managementIdentity creation and validation on-chainAgent discovery via service endpointsSecure handshake initiation and completion between agentsThese utilities combine identity creation, verification, and secure message exchange — allowing any AI agent to operate as a verifiable on-chain entity.Technical StackLangChain JS – for LLM-driven agent behaviorHedera Agent Kit – base framework for agent developmentHedera JS SDK – on-chain interaction layerGoogle A2A Protocol (npm) – agent communication protocolCustom ERC-8004-inspired Registry Contract – for agent registration and lookupNode.js + TypeScript – for plugin and agent developmentChallenges & HacksPackaging the npm module with blockchain calls and crypto functions was trickyAdapting ERC-8004 concepts to Hedera required architectural tweaksExtending A2A to include runtime signature verification pushed the limits of current SDKs