x402 Notary MCP runs on your own machine — the client starts it, so there is no endpoint to ping. 75 installs a week from npm. Last commit 1 Sep 2026.
Cryptographic receipts for AI outputs on Base or Solana via x402.
Today is the operative word: we check x402 Notary MCP every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.
This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.
claude mcp add x402-notary-mcp -- npx -y @forgemeshlabs/x402-notary-mcp
{
"mcpServers": {
"x402-notary-mcp": {
"args": [
"-y",
"@forgemeshlabs/x402-notary-mcp"
],
"command": "npx"
}
}
}
[mcp_servers.x402-notary-mcp]
command = "npx"
args = ["-y", "@forgemeshlabs/x402-notary-mcp"]
{
"mcpServers": {
"x402-notary-mcp": {
"args": [
"-y",
"@forgemeshlabs/x402-notary-mcp"
],
"command": "npx"
}
}
}
{
"mcpServers": {
"x402-notary-mcp": {
"args": [
"-y",
"@forgemeshlabs/x402-notary-mcp"
],
"command": "npx"
}
}
}
This one needs environment variables set before it will start:
WALLET_PRIVATE_KEY (Dedicated low-balance Base wallet private key for x402 USDC micropayments. Optional — verification tools work without it. Never use your primary wallet.), NOTARY_RAIL (Payment rail: base or solana. Defaults to base, or solana when NOTARY_BASE_URL contains notary-solana.), NOTARY_BASE_URL (Notary API origin. Use https://notary.forgemesh.io for Base or https://notary-solana.forgemesh.io for Solana.), SOLANA_PRIVATE_KEY (Dedicated low-balance Solana keypair for x402 USDC micropayments. Supports JSON byte array, base58, base64, or hex. Optional — verification tools work without it.).
The author declared them in the registry entry; get the values from the project itself.
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Answers built from our own checks of this server.