Glossary

Agent Discovery & Registries

HCS-14 / HOL (Hashgraph Online / Hedera) – Hedera consensus-based universal agent ID standard using deterministic DIDs for protocol-agnostic agent identification. info@hashgraphonline.com
HCS-10 (Hashgraph Online / Hedera) – Hedera-based agent messaging standard for real-time secure communication and registry-backed routing.
HCS-11 (Hashgraph Online / Hedera) – Hedera registry for agent profile metadata, public keys, and MCP server discovery.
Registry Brokers (Hashgraph Online/Hedera) Consensus-based discovery and communication for agents anywhere on the planet. Supports & integrates with all registries including: Virtuals, A2A, ERC-8004, x402 Baazar, OpenConvAI, and more.
NANDA (ProjectNanda.org, originated at MIT) – Multi-layer decentralized agent index and agent facts card with verifiable interaction logs and auditability for large-scale agent ecosystems. (hello@agenticnet.org)
ANS (Agent Name Service) (Academic/Collaborators/IETF draft) – DNS-inspired agent naming and discovery system using PKI certificates and protocol adapters.
KYA (Know Your Agent) (Skyfire, Vouched, contributors) – Community-driven protocol for KYC-style verification, trust badges, and fraud prevention for AI agents.
ANP (Agent Network Protocol) (Agent Network Protocol Foundation) – Protocol for decentralized agent identity, protocol negotiation, and open agent marketplaces.

ERC-8004 (Ethereum Foundation) – Ethereum on-chain agent identity and reputation registry based on ERC‑721 tokens .https://github.com/ethereum/EIPs ·
FPP (First Person Protocol) (Trust Over IP, Futurewei) – Trust Over IP protocol for first-person verifiable credentials and provenance for agents. contact@trustoverip.org
Trust Over IP (ToIP) (LF Trust, DIF, Sovrin) – Linux Foundation framework for decentralized digital trust using DIDs, credentials, and layered governance. contact@trustoverip.org

UCAN (Fission / Brooklyn Zelenka) – Capability-based authorization tokens for delegated agent permissions and storage access.https://github.com/ucan-wg
OpenID 4 VC (OpenID Foundation) – OpenID standard for issuing and presenting verifiable credentials with OAuth 2.0 flows. contact@openid.net

W3C DIDs (W3C) – Web standard for decentralized identifiers used as portable, verifiable agent IDs. public-ccg@w3.org

W3C Verifiable Credentials (W3C) – Data model for cryptographically verifiable claims about agents and entities.public-ccg@w3.org

Affinidi (Affinidi) – DIDComm and W3C VC–based platform for passwordless login, credentials, and secure messaging between agents.

MCP (Anthropic, OpenAI, Google) – Model Context Protocol enabling agents to call tools, access data, and share context. support@modelcontextprotocol.io

OASF (Open Agentic Schema Framework) (AGNTCY / Cisco Outshift) – AGNTCY open framework for standardizing agent tool schemas, capabilities, and action specifications.

ACP (Agent Context Protocol) (Cisco / AGNTCY) – OpenAPI-based agent context sharing protocol for sharing state and context among agents.

A2A (Agent-to-Agent) (Google & partners) – Google-led protocol for direct agent-to-agent communication, messaging, and coordination with 50+ partners. partners@a2aprotocol.ai

AGNTCY (Cisco Outshift, Linux Foundation) – Cisco Outshift and Linux Foundation infrastructure protocol for agent orchestration and multi-agent coordination.

Open Agent Protocol (OAP) (LangChain/LangGraph Community) – LangChain/LangGraph community protocol for agent communication and coordination patterns.
Swarm Protocol (Ethereum / Swarm Foundation) – Ethereum Swarm protocol adapted for multi-agent coordination and decentralized agent discovery. info@ethswarm.org

Agora Protocol (Oxford University AI Institute) – Oxford University AI Institute protocol for agent communication and decentralized agent marketplaces.

HumanAIX (HumanAIX Foundation) – Multimodal human-in-the-loop interaction and workflow protocol for AI agents. team@humanaix.org

Super Protocol (Super Protocol Labs / Filecoin / Ethereum) – Confidential computing and decentralized AI cloud for running privacy-preserving agent workloads.

IEEE 2874–2025 (Spatial Web Protocol) (IEEE SA, Verses) – IEEE standard for spatial, semantic identity and context sharing across Web3, IoT, and XR systems. contact@ieee.org

x402 (Coinbase, Web3 Ecosystem) – HTTP 402 payment protocol enabling stablecoin micropayments for agent services using 402 status codes. dev@x402.org

AP2 (Agent Payments Protocol) (Google, PayPal, Mastercard) – Google, PayPal, Mastercard protocol for agent-to-agent and agent-to-human payment settlement. dev@ap2-protocol.org

ACP (Agentic Commerce Protocol) (Stripe, OpenAI) – Stripe and OpenAI protocol enabling agents to execute commerce transactions and payment flows. acp@stripe.com

Trusted Agent Protocol (Cloudflare, Visa, Mastercard, Amex) – Cloudflare, Visa, Mastercard protocol for agent trust verification and behavioral validation.

NEAR AITP (AI Trusted Protocol) (NEAR Foundation / AITP Alliance) – Smart-contract framework for verifiable agent execution and cross-chain trust on NEAR and EVM. aitp-info@near.org

IETF AI Agent Protocols Framework (IETF) – Meta-framework from IETF working group providing foundations for standardizing AI agent protocols. ietf@ietf.org
IEEE P3394 (AI Agent Interoperability) (IEEE Standards Association) – IEEE standard for agent-to-agent and agent-to-system interoperability frameworks. contact@ieee.org
IEEE SA IC25-003 (Multi-Agent Evaluation) (IEEE Standards Association Industry Connections) – Framework for evaluating multi-agent systems reasoning about novel, complex problems.