Open interoperability infrastructure for AI agents.
HOL builds open standards, registry infrastructure, SDKs, and reference implementations that help AI agents, MCP servers, skills, tools, wallets, registries, and payment systems work together.
Use HOL to discover agents, register services, resolve portable agent IDs, route across protocols, and attach trust, privacy, and provenance signals without wiring every ecosystem by hand.
HOL standards are developed in the open through the HCS process and use Hedera Consensus Service where verifiable ordering, audit trails, and durable public records are useful.
HOL Guard is an AI security layer that scans plugins, MCP servers, skills, and agent tooling before tools run. It protects Codex, Claude Code, Cursor, Gemini, OpenCode, and other AI harnesses from malicious or risky code.
- Scan plugins before install — detect prompt injection, data exfiltration, and unsafe file access
- Verify MCP servers against a registry of known-safe tools
- Lint agent skills for compliance with HOL trust and privacy standards
- Publish readiness — plugins that pass HOL Guard scans earn a verification badge in the plugin registry
# Install HOL Guard
pip install hol-guard
# Scan a plugin or MCP server
hol-guard scan ./my-plugin
# Verify a published plugin
hol-guard verify --plugin my-plugin-slugThe @hashgraphonline/standards-sdk provides TypeScript libraries for HCS standards — agent identity, registries, communication, and more.
npm install @hashgraphonline/standards-sdkimport { HCS14Client, HCS11Client } from '@hashgraphonline/standards-sdk';
// Resolve a Universal Agent ID (HCS-14)
const hcs14 = new HCS14Client({
network: 'mainnet',
operatorId: process.env.HEDERA_ACCOUNT_ID!,
privateKey: process.env.HEDERA_PRIVATE_KEY!,
});
const profile = await hcs14.resolveUaidProfile('uaid:hiero:mainnet:0.0.12345');
// Create an agent profile (HCS-11)
const hcs11 = new HCS11Client({
network: 'mainnet',
auth: {
operatorId: process.env.HEDERA_ACCOUNT_ID!,
privateKey: process.env.HEDERA_PRIVATE_KEY!,
},
});
const result = await hcs11.createAndInscribeProfile({
name: 'My Agent',
bio: 'An AI assistant for developer workflows.',
});Browse the SDK docs → https://hol.org/docs
| Asset | What it does |
|---|---|
| Universal Agentic Registry | Discover agents, MCP servers, skills, and plugins across protocols |
| Registry Broker | Route agent discovery queries across registries and protocols |
| Standards SDK | TypeScript libraries for HCS standards — identity, registries, communication |
| HOL Guard | AI antivirus — scan and verify plugins, MCP servers, and skills before tools run |
| Universal Agent IDs / HCS-14 | Portable, cross-protocol agent identifiers with DNS and DID proofs |
| OpenConvAI / HCS-10 | Agent communication standard for messaging and presence |
| Agent Profiles / HCS-11 | Metadata, capabilities, and service discovery for agents |
| Skills & Verification | Plugin scanning, trust signals, and attestation infrastructure |
| Area | Examples |
|---|---|
| Agent discovery | Universal Agentic Registry, HCS-2 registries, HCS-21 capability attestations |
| Agent identity | HCS-11 profiles, HCS-14 UAIDs, DNS/domain proofs |
| Communication | HCS-10/OpenConvAI, adapter-based routing for A2A and XMTP |
| Tooling | MCP servers, skills, plugins, SDK integrations |
| Trust and provenance | HOL Guard scanning, verification signals, attestations, audit trails |
| Payments and intents | Agent commerce/payment metadata, working group exploration |
| Privacy and governance | Enterprise audit patterns, privacy working group |
Adapter work includes cross-protocol routing for A2A and XMTP where supported.
AI-agent infrastructure standards, prioritized:
| Standard | Title | Status |
|---|---|---|
| HCS-10 | OpenConvAI — agent communication | Published |
| HCS-11 | Profiles — agent/service metadata | Published |
| HCS-14 | Universal Agent IDs — portable agent identifiers | Published |
| HCS-2 | Discovery Registries | Published |
| HCS-20 | Auditable Points — transparent incentives/rewards | Published |
| HCS-21 | Agentic Data Registries — discovery/capability attestations | Published |
| HCS-1 | File Storage & Retrieval | Published |
| HCS-3 | Resource Linking & Recursion | Published |
Full standards catalog → https://hol.org/docs/standards
| If you want to... | Start here |
|---|---|
| Search or register agents | Universal Agentic Registry |
| Scan a plugin for safety | HOL Guard CLI |
| Build with HOL standards | Standards SDK |
| Add discovery to an assistant | Registry Broker |
| Build HCS-10 agents | Standards SDK HCS-10 modules |
| Propose a standard | hcs-improvement-proposals |
| Explore examples | Quickstarts and demos |
- Propose or review a standard — open issues and PRs in hcs-improvement-proposals
- Build protocol adapters — help extend cross-protocol routing
- Publish agents, skills, or MCP servers — list them in the registry
- Improve SDK examples — PRs welcome in standards-sdk
- Contribute test vectors — see each repo's
CONTRIBUTING.md - Open issues/PRs — follow each repo's contribution guidelines
- Website: https://hol.org
- Registry: https://hol.org/registry
- Docs: https://hol.org/docs
- X (Twitter): @HashgraphOnline
- Telegram: https://t.me/hashinals
- Brand kit: https://hol.org/brand
- Blog: https://hol.org/blog
Unless noted otherwise, HOL software is released under Apache-2.0.
Check each repository's LICENSE for details.
