Documentation

Build on x402 Agentic

Everything you need to integrate autonomous payments into your APIs, agents, and applications. Start with the quickstart — be live in under 5 minutes.

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Start Here

Quickstart

Accept your first x402 payment in under 5 minutes. No wallet setup required for testing.

Read guide →

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Beta

Agent Wallets

Give your AI agent its own wallet with spend limits, daily caps, and audit trails.

Read guide →

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Q2 2026

Middleware

One line to monetize any API endpoint. Works with Express, FastAPI, Next.js, Cloudflare Workers.

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Q2 2026

SDK Reference

Full API reference for the x402 Agentic JavaScript/TypeScript and Python SDKs.

Browse reference →

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Live

x402 Protocol V2

How HTTP 402 payment flows work under the hood — request lifecycle, headers, and verification.

Deep dive →

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Q2 2026

MCP × x402 Bridge

Drop payments into any MCP server. Claude, GPT-4, Gemini — any model can pay for tools.

Preview →

Protocol Integrations

x402 Agentic is built on top of open standards. Understanding these protocols helps you build more powerful integrations.

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x402 Protocol V2 ● Live

The HTTP 402 payment standard by Coinbase + Cloudflare. V2 adds multi-chain CAIP support, an extensions system, and a modular facilitator SDK. The foundation of everything x402 Agentic builds on.

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ERC-8004 ● Live

Ethereum standard for autonomous agent identity and on-chain reputation. Live on mainnet since Jan 29 2026. Agents get a verifiable identity that persists across services and builds trust over time.

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Google AP2 / A2A ● Integrating

Google's Agent Payments Protocol uses x402 as its crypto payment rail. The A2A (Agent-to-Agent) protocol handles agent communication. x402 Agentic bridges both for seamless agent commerce.

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MCP (Model Context Protocol) ● Coming Q2

Anthropic's protocol for AI model tool use. The x402 × MCP Bridge lets any MCP server charge per tool call. Claude, GPT-4, Gemini, and any MCP-compatible model can pay autonomously.

Recent Updates