Registry Broker Plugin for Hedera Agent Kit

| | @hol-org/rb-hak-plugin brings the Hashgraph Online Registry Broker directly into Hedera Agent Kit so agents can discover, chat with, and register peers from within workflows.Built and maintained by Hashgraph Online.📚 Registry Broker Quickstart · 📦 Standards SDK | | :-------------------------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |

Features

• Full coverage of the Registry Broker REST API (search, registration lifecycle, ledger auth, encryption helpers).
• Seamless conversation handle management so agents can continue chats (encrypted or plaintext) without re-fetching handles.
• Reuses the Hedera Agent Kit Client operator (ledger-auth only) and falls back to API keys when necessary.
• Live integration test + Hedera Agent Kit demo that hit the production Registry Broker (no mocks).
• Matches the Registry Broker Quickstart so every HTTP capability is exposed to agents.

Installation

pnpm add @hol-org/rb-hak-plugin hedera-agent-kit

Quickstart

import { HederaLangchainToolkit, AgentMode } from 'hedera-agent-kit';
import {
  createRegistryBrokerPlugin,
  registryBrokerPluginToolNames,
} from '@hol-org/rb-hak-plugin';

const toolkit = new HederaLangchainToolkit({
  client,
  configuration: {
    plugins: [createRegistryBrokerPlugin()],
    tools: [registryBrokerPluginToolNames.REGISTRY_BROKER_OPERATION_TOOL],
    context: { mode: AgentMode.AUTONOMOUS },
  },
});

const registryTool = toolkit.getTools().find(
  tool => tool.name === registryBrokerPluginToolNames.REGISTRY_BROKER_OPERATION_TOOL,
);

Environment

Use the same Hedera operator credentials you already provide to Hedera Agent Kit (client.setOperator(...) or env vars such as HEDERA_OPERATOR_ID / HEDERA_OPERATOR_KEY, or ACCOUNT_ID as the account id). The plugin inspects the Client you pass to Hedera Agent Kit and reuses its operator + signer for Registry Broker ledger authentication—no duplicate REGISTRY_BROKER_LEDGER_* secrets are required.

Optional:

• HEDERA_NETWORK (defaults to hedera:testnet; set hedera:mainnet to force mainnet).
• REGISTRY_BROKER_API_KEY for API-key-only flows.
• REGISTRY_BROKER_DEMO_UAID to override the default OpenRouter UAID used by the demo.

If you rely on .env to set those values locally, create it inside this repo (never reference secrets from sibling projects).

Commands

pnpm run lint       # ESLint over src
pnpm run typecheck  # tsc --noEmit
pnpm test           # unit + live integration test
pnpm demo:hedera-kit # run the Langchain demo script
pnpm run release    # install, build, and publish with pnpm

Hedera Agent Kit Demo

Run the end-to-end demo to see the plugin registered with a real Hedera Agent Kit (HederaLangchainToolkit) instance. The script:

1. Loads the Registry Broker plugin into Hedera Agent Kit using the same operator account that powers your toolkit client.
2. Runs a live search against the Registry Broker.
3. Starts a chat session with a UAID, sends a message, fetches history, and closes the session.

pnpm demo:hedera-kit

Required environment: HEDERA_OPERATOR_ID (or ACCOUNT_ID) + HEDERA_OPERATOR_KEY (or equivalent MAINNET_* variables) so Hedera Agent Kit can set its operator. Set REGISTRY_BROKER_DEMO_UAID only if you want to test your own UAID; otherwise the script falls back to the bundled OpenRouter agent.

Docs & Resources

• Registry Broker Quickstart
• Hashgraph Online Standards SDK
• Hedera Agent Kit