Glossary

x402

An HTTP-native payment protocol built on 402 Payment Required. Clients pay for resources at request time — no API keys, no subscriptions.

Facilitator

The service that verifies payment payloads, sponsors transaction fees (on Solana), and settles transactions on-chain. Dexter's public facilitator lives at https://x402.dexter.cash.

OpenDexter

The public, no-auth x402 gateway for searching and paying for paid APIs. Available as a hosted MCP server at open.dexter.cash/mcp and as the @dexterai/opendexter npm package.

Dexter MCP

The authenticated MCP server at mcp.dexter.cash/mcp with managed wallets and broader platform tooling.

@dexterai/x402

Dexter's SDK for integrating x402 payments into client and server applications. Includes Express middleware, React hooks, browser client, and pricing models.

Merchant / Seller

A developer or operator exposing a paid endpoint through x402.

Resource

A paid endpoint or API that returns 402 Payment Required with x402 payment requirements. Discoverable through the OpenDexter marketplace.

Payment Requirements

The JSON returned with a 402 response that tells the client which chains, assets, and amounts are accepted.

Settlement

Verifying, signing, and finalizing a payment transaction on-chain through the facilitator.

Verification

Dexter's AI quality evaluation that tests whether a resource actually works and delivers useful responses. Produces a 0-100 score and letter grade.

Access Pass

An SDK mode where the buyer pays once for a time window (e.g. 1h, 24h) instead of signing every request.

CAIP-2

Chain Agnostic Identifier format for naming networks. Examples: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp (Solana mainnet), eip155:8453 (Base).

Dexter Lab

The AI-powered builder that creates, deploys, and publishes paid APIs from a chat interface at lab.dexter.cash.

ERC-8004

On-chain identity standard for resources. Lab-deployed APIs get an ERC-8004 identity on Solana or Base.