datasieve-mcp

MCP server for DataSieve — standing infrastructure for AI agents, paid over x402. On-chain conditions on Base (wallet activity, whale transfers, price crossings, new pools), url-change web monitoring (CSS selector / regex scoped), dead-man switches for your own agents (your agent pings a URL; silence fires the alert), cron schedules (fire a webhook every N seconds, at a time, or on a cron expression), and multi-agent coordination (barriers + locks). Every event carries a signed Ed25519 observation receipt. No account, no API key: one gasless USDC payment per watch, signed locally — your key never leaves your machine. Failed calls are never billed.

Setup — no key required to start

claude mcp add datasieve -- npx -y datasieve-mcp

Most tools work with no wallet at all — check our scanner's health, read watch status, drain events, ping dead-man switches, pause/resume, verify receipts, cancel watches. Only the buying tools spend money.

The Claude Code skill (recommended)

npx -y datasieve-mcp --install-skill

Installs a skill into ~/.claude/skills/datasieve/ that teaches Claude when to reach for standing infrastructure proactively: arm a dead-man switch before long autonomous work, schedule wake-ups, watch pages and wallets, coordinate sub-agents.

When you want to buy

x402 means paying is a signature, so purchases need a key. Two rules:

1. Use a dedicated burner wallet holding a few dollars of USDC on Base — never your main wallet. Payments are gasless (EIP-3009), so it needs no ETH.

2. Keep the key out of config files — point at a file instead:

echo '0xYOUR_BURNER_KEY' > ~/.datasieve/key.txt && chmod 600 ~/.datasieve/key.txt
claude mcp add datasieve -e DATASIEVE_PRIVATE_KEY_FILE=$HOME/.datasieve/key.txt -- npx -y datasieve-mcp

(DATASIEVE_PRIVATE_KEY=0x... inline also works if you prefer.)

The key never leaves the process: each payment is a signature authorizing exactly the route price — one at a time, nothing standing. Run payment_status to see the wallet, its balance, and prices before spending anything.

Rehearse for free

claude mcp add datasieve-sandbox -e DATASIEVE_API_URL=https://staging.datasieve.xyz \
  -e DATASIEVE_PRIVATE_KEY_FILE=$HOME/.datasieve/key.txt -- npx -y datasieve-mcp

Same API, Base Sepolia, faucet USDC. Sandbox watches last 1 hour.

Related MCP server: Pylon MCP Server

Tools

Watch ids and secrets are remembered in ~/.datasieve/watches.json (mode 600), so follow-up calls only need the watch id — the persistent memory your ephemeral agent lacks.