Fast

What is Fast?

Fast is a unified payment and shopping infrastructure designed specifically for AI agents. It enables agents to search shops, compare products, prepare quotes, and initiate checkout flows through a single integration called fast-mcp. Merchants and buyers can transact seamlessly without needing separate payment accounts or complex setup. The platform currently lists a merchant directory of stores you can buy from right now, with more being onboarded.

Application scenarios

AI agent shopping
Agents like Claude Desktop, Claude Code, and OpenCode can browse merchant catalogs, compare products, and prepare quotes autonomously.
Cross-store price comparison
Agents can use `fast_shop_search` and `fast_shop_quote` to compare products and delivered prices across multiple merchants.
Guarded checkout handoff
The system requires explicit user confirmation before completing any order, making it suitable for high-stakes purchases.
Merchant onboarding
New merchants can join the directory and become discoverable by AI agents without building custom integrations.
Self-checkout mode
When a merchant's `checkoutModes` only includes "self," or the buyer opts out of Fast Checkout, the agent prepares the merchant's own checkout flow.

Core Features

fast-mcp MCP bundle
A single `.mcpb` file that installs the Fast MCP server on your machine, giving your agent access to all supported merchants.
Merchant directory
A live list of stores your agent can buy from right now, with new merchants being added regularly.
Search and quote flow
Agents call `fast_shop_list_merchants` first, then use `fast_shop_search` and `fast_shop_quote` to compare products and get delivered-price quotes before any checkout step.
Explicit checkout confirmation
Order and handoff tools are guarded boundaries—the agent must get explicit user action/confirmation before completing a purchase.
Multi-platform support
Works with Claude Desktop, Claude Code, and OpenCode via standard MCP configuration.
One-shot install
A single curl command downloads, extracts, and registers the MCP server with your agent client.
Environment variable configuration
Uses `MARKETPLACE_API_BASE_URL` and `FAST_NETWORK` to point the agent to the correct marketplace and network (mainnet).

Target users

AI developers building agentic shopping experiences, merchants who want to be discoverable by AI agents, and end users who want to let their Claude or OpenCode agents shop on their behalf. The platform is also useful for anyone running Claude Desktop, Claude Code, or OpenCode who wants to automate purchasing.

How to use Fast?

Install fast-mcp on your machine using the provided curl command for your agent client (Claude Desktop, Claude Code, or OpenCode).
Configure the MCP server by setting the environment variables MARKETPLACE_API_BASE_URL and FAST_NETWORK to mainnet.
Start your agent—it will auto-discover all fast_shop_* tools on next startup.
Let your agent shop by calling fast_shop_list_merchants first, then searching and quoting products, and finally completing checkout with your explicit confirmation.

Effect review

Fast delivers exactly what it promises: a dead-simple way to let AI agents shop across multiple merchants without custom integration work. The one-command install and explicit checkout guardrails make it practical for real-world use, especially for developers who trust their agents but want a safety net. The merchant directory is still loading, so the available selection is limited right now, but the underlying MCP architecture is solid. For anyone running Claude Desktop or OpenCode, this is the most straightforward agent shopping solution available today.

Frequently Asked Questions

What is Fast by Fast?

Fast by Fast is a unified payment solution designed for AI agents and merchants, enabling seamless and simple transactions.

How does Fast handle payments for AI agents?

Fast provides a single, unified payment system that allows AI agents to process transactions effortlessly without integrating multiple payment methods.

Is Fast compatible with any merchant platform?

Yes, Fast is designed to work with any merchant platform, offering a simple integration for accepting payments from AI agents.

What types of transactions does Fast support?

Fast supports a wide range of digital transactions, including microtransactions and standard payments, tailored for AI agent interactions.

Does Fast require additional setup for AI agents?

No, Fast is built as a plug-and-play solution, requiring minimal setup for AI agents to start processing payments.

Is Fast secure for handling payments?

Yes, Fast employs industry-standard security measures to ensure all transactions are safe and encrypted.