openclaw-x402

OpenClaw plugin for x402 USDC payments on Solana. Handles LLM inference billing automatically, and gives the agent tools to discover and pay for external x402 services.

What it does

Fetch interception (automatic):

• Intercepts outgoing fetch calls to your configured provider URL
• Handles 402 Payment Required responses using the x402 protocol
• Signs USDC SPL token payments from a local Solana keypair

Agent tools (AI-callable):

• x402_balance - check wallet balance with available/reserved breakdown
• x402_payment - call any x402-enabled paid API with automatic USDC payment
• x402_discover - search the zauth verified provider directory for paid services

User commands (slash commands):

• /x402_balance - show wallet address and USDC balance
• /x402_send - send USDC to a Solana address

Installation

npm install openclaw-x402

Add to your OpenClaw plugin config:

{
  "plugins": [
    {
      "package": "openclaw-x402",
      "config": {
        "providerUrl": "https://your-x402-provider.example.com",
        "keypairPath": "/path/to/solana/id.json"
      }
    }
  ]
}

Configuration

| Field | Required | Default | Description | |---|---|---|---| | providerUrl | Yes | - | Base URL of the x402-enabled provider to intercept | | keypairPath | No | ~/.openclaw/agentbox/wallet-sol.json | Path to Solana keypair JSON | | providerName | No | blockrun | Provider ID for OpenClaw registration | | rpcUrl | No | https://api.mainnet-beta.solana.com | Solana RPC endpoint | | models | No | built-in list | Array of model objects from backend config. When provided, overrides the hardcoded model catalog. |

Inference reserve

$0.30 USDC is reserved for LLM inference and cannot be spent by agent tools. This prevents the agent from spending all funds on external APIs and losing the ability to respond.

Funding the wallet

1. Run /x402_balance to get your wallet address
2. Send USDC (SPL token on Solana mainnet) to that address
3. Keep a small amount of SOL (0.001+) for transaction fees

How it works

On startup the plugin loads the keypair, creates an x402 client with ExactSvmScheme for Solana mainnet, and replaces globalThis.fetch with a wrapper. Any request to providerUrl goes through x402 payment handling. All other requests pass through unmodified. Agent tools use the same x402 fetch wrapper to pay for external endpoints.

License

Apache-2.0 - see LICENSE.