Hedera Agent Trust

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.

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 Overview

Each 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 Capabilities

The npm plugin provides 9 tools for developers:

Agent DID generation and signature management

Identity creation and validation on-chain

Agent discovery via service endpoints

Secure handshake initiation and completion between agents

These utilities combine identity creation, verification, and secure message exchange — allowing any AI agent to operate as a verifiable on-chain entity.

Technical Stack

LangChain JS – for LLM-driven agent behavior

Hedera Agent Kit – base framework for agent development

Hedera JS SDK – on-chain interaction layer

Google A2A Protocol (npm) – agent communication protocol

Custom ERC-8004-inspired Registry Contract – for agent registration and lookup

Node.js + TypeScript – for plugin and agent development

Challenges & Hacks

Packaging the npm module with blockchain calls and crypto functions was tricky

Adapting ERC-8004 concepts to Hedera required architectural tweaks

Extending A2A to include runtime signature verification pushed the limits of current SDKs