Agent Standards
See which tools in the directory are built on each agent standard.
x402
91 listings
Every tool in the directory that speaks x402 — the standard that lets agents pay for APIs in stablecoins over HTTP, with no account and no API key. Each scored on how open, active, and verifiable it is.
Model Context Protocol
200 listings
Onchain tooling that exposes a Model Context Protocol interface — the open standard for giving agents tools. Each listing scored on how open, active, and verifiable it is.
ERC-8004
17 listings
Projects working with ERC-8004, the Trustless Agents standard giving agents an onchain identity and reputation surface. Each scored on how open, active, and verifiable it is.
Agent2Agent
14 listings
Tooling that implements Agent2Agent, the protocol for agents to discover each other and hand off tasks. Each listing scored on how open, active, and verifiable it is.
Unsure what any of these words mean? The glossary defines each one — what it is, how it works and what it is not — with a primary source and the page that measures it.
Which standards get a pageShowHide
A standard gets a page here once at least ten live listings implement it. Below that the page would be a stub pretending to be a survey, so ERC-8183 and the agent-checkout specs stay tracked in the directory until they clear the bar.
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