WORDS · Glossary8 terms · plain EnglishReference
Reference
The agent economy in 8 words.
Every term that appears anywhere on this site, defined here in language that doesn’t assume crypto fluency.
- x402
- A way for software to pay other software automatically, using the long-forgotten HTTP "402 Payment Required" status code. No accounts, no API keys, no invoices.
- agent
- A program (often built on top of an LLM) that decides what to do on your behalf. When it needs data or compute it doesn’t have, it pays for it.
- MCP
- Model Context Protocol, a standard way for agents to plug into tools and data sources. An MCP server can be free or paid; if paid, it usually charges via x402.
- facilitator
- A server that watches the blockchain and tells an API "yes, the agent paid you." Removes the need for the API to run its own crypto stack.
- USDC
- A digital dollar that lives on a blockchain. One USDC = one US dollar. x402 uses USDC for payments because it settles in under a second.
- split
- When a single payment is automatically divided between several wallets, for example, the API operator, the platform that sent the agent, and the protocol itself.
- gate
- A small wrapper that sits in front of your API and turns it into an x402-payable endpoint. With Chest Gate, deploying one is a single command.
- referrer
- The platform, agent host, or developer that brought a paying agent to an API. With trustless splits, the referrer earns a share of every payment they originate.
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