Coal — Payments For AI Agents
Let AI agents pay merchants in USDC on Base through Coal checkout and dual payment protocols.
Overview
Coal MCP is a Build-phase MCP server that gives AI agents USDC payment rails on Base via x402 and OKX APP.
What is this MCP server?
- USDC payments on Base with wallet signing via EIP-3009
- Dual-protocol support: x402 and OKX APP
- Remote streamable-http MCP at mcp.usecoal.xyz/api/mcp
- Optional X-Coal-Agent-Key (wallet) and X-Coal-Api-Key for checkout and merchant memory
- Read-only Coal tools work without keys; v1.3.0 server
- Server version 1.3.0; schema 2025-12-11
- Remote URL: https://mcp.usecoal.xyz/api/mcp
- Two optional secret headers: X-Coal-Agent-Key and X-Coal-Api-Key
Community signal: 1 GitHub stars.
What problem does it solve?
Agents cannot complete real merchant purchases or agent-native checkouts without a standardized on-chain payment and signing integration.
Who is it for?
Builders shipping agent products that must pay APIs, merchants, or x402-gated resources in USDC on Base.
Skip if: Teams needing only human-driven fiat checkout without agent wallets or on-chain USDC.
What do I get? / Deliverables
Your agent can pay in USDC on Base and use Coal checkout tools when keys are configured, with read paths available keyless.
- Agent-callable USDC payment and checkout tools on Base
- Dual-protocol x402 and OKX APP payment paths
- Merchant memory queries when Coal API key is configured
Recommended MCP Servers
Journey fit
Payment rails are wired during Build when you connect agent capabilities to real money movement and merchant APIs. Integrations is the shelf for MCP servers that extend agents with third-party payment and checkout APIs.
How it compares
Agent payment MCP on Base, not a competitive-research or conversation-memory server.
Common Questions / FAQ
Who is Coal MCP for?
Solo builders and small teams building agents that need programmatic USDC payments and Coal checkout on Base.
When should I use Coal MCP?
When you integrate paid agent workflows, x402 paywalls, or merchant checkout that must settle in USDC rather than manual card flows.
How do I add Coal MCP to my agent?
Point your MCP client at https://mcp.usecoal.xyz/api/mcp (streamable-http); add X-Coal-Agent-Key for signing and X-Coal-Api-Key from usecoal.xyz/console/keys for checkout tools.