openclaw-x402-skill

Discover x402 APIs and execute pay-per-call endpoints with USDC on Base.

Updated Mar 3, 2026

Search Tags:#MCP #service discovery #micropayments #x402 #Base #USDC #agentic payments

Ready to run

npx skills add https://github.com/coinvest518/openclaw-x402-skill --skill openclaw-x402-skill

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: openclaw-x402-skill
Source: https://github.com/coinvest518/openclaw-x402-skill/tree/main
Command: npx skills add https://github.com/coinvest518/openclaw-x402-skill --skill openclaw-x402-skill

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

x402 discovery removes the need to preconfigure API keys or subscriptions, while x402 payments let agents pay only when an endpoint is actually used.

Core Features & Use Cases

Autonomous x402 service discovery: Browse and search the x402 Bazaar, then filter by price, type (HTTP/MCP), and keywords for tasks like weather, scraping, and AI inference.
Pay-per-call execution with micropayments: Handle the HTTP 402 payment-required handshake and execute a paid call using USDC on Base for one-off endpoint usage.
MCP tool integration readiness: Expose x402-compatible endpoints as MCP tools so Claude Desktop (and other MCP clients) can discover and call paid APIs without manual payment steps.

Quick Start

Ask your AI agent to "find the cheapest weather API on x402 under 0.01 USDC and get weather for London" (paid calls require EVM_PRIVATE_KEY in .env with USDC on Base).

Frequently Asked Questions about openclaw-x402-skill

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I handle HTTP 402 payment-required responses for autonomous API calls?▼

The Skill handles HTTP 402 payment-required responses for autonomous API calls by automatically processing the x402 handshake and generating payment proofs using USDC on Base. It manages the entire pay-per-call execution flow so agents can access endpoints without preconfigured API keys or subscriptions.

What are agentic micropayments and how do they work on Base?▼

Agentic micropayments on Base are pay-per-call USDC transactions that let AI agents autonomously access x402-compatible APIs without preconfigured API keys. The Skill executes the HTTP 402 handshake, verifying payment requirements and transferring funds via an EVM private key with defined spending limits.

How do I discover and filter MCP tools by price for agent workflows?▼

To discover and filter MCP tools by price for agent workflows, the Skill searches the x402 Bazaar and applies filters for cost, endpoint type, and keywords. This enables browsing available HTTP and MCP services, inspecting payment requirements, and identifying the cheapest options matching specific task criteria.

Do I need a crypto wallet to use x402 API discovery and execution?▼

Yes, a crypto wallet configured via the EVM_PRIVATE_KEY environment variable is required to execute paid calls with x402 APIs. While service discovery in the x402 Bazaar requires no wallet, completing USDC micropayments on Base for pay-per-call execution requires valid wallet credentials.

How do I set spending limits for autonomous API micropayments?▼

You set spending limits for autonomous API micropayments by configuring the MAX_SPEND_PER_CALL guardrail. This prevents unexpected costs during pay-per-call execution by ensuring the agent does not exceed a defined budget threshold when handling the x402 payment handshake on Base.

Can I use x402 endpoints as MCP tools in Claude Desktop?▼

Yes, x402 endpoints can be used as MCP tools in Claude Desktop and other MCP clients. The Skill exposes x402-compatible APIs as MCP tools, enabling clients to discover and call paid APIs autonomously without manual payment steps by handling the USDC micropayment handshake on Base.