cron402-mcp

cron402-mcp

MCP server for cron402 — schedule webhook calls and pay per run in USDC on Base via x402. No accounts, no API keys; your wallet is the credential.

Built so that small models can drive it safely: schedules can be written in plain English, every schedule can be validated for free before a paid call, and every response carries an explicit next_step telling the model what to do next.

Price: $0.008 USDC per run · Network: Base mainnet (eip155:8453)

Quick start

export CRON402_PRIVATE_KEY=0x...   # fund with USDC on Base
npx -y cron402-mcp

Optional env vars:

Variable	Default	Description
CRON402_PRIVATE_KEY	(required for paid tools)	Agent wallet private key. Without it the server still starts and the free tools work.
CRON402_NETWORK	eip155:8453	CAIP-2 id; use eip155:84532 for Base Sepolia
CRON402_API_URL	production Worker	Override API base URL
CRON402_STATE_DIR	~/.cron402	Where created job ids are remembered for list_crons

MCP client config

Cursor / Claude Desktop:

{
  "mcpServers": {
    "cron402": {
      "command": "npx",
      "args": ["-y", "cron402-mcp"],
      "env": {
        "CRON402_PRIVATE_KEY": "0x..."
      }
    }
  }
}

OpenCode (opencode.json):

{
  "mcp": {
    "cron402": {
      "type": "local",
      "command": ["npx", "-y", "cron402-mcp"],
      "environment": {
        "CRON402_PRIVATE_KEY": "0x..."
      },
      "enabled": true
    }
  }
}

Tools

Tool	Cost	Description
cron402_guide	free	The whole procedure, prices and rules — the tool a model should read first
check_wallet	free	Address, network, USDC/ETH balance, and how many runs it can afford
preview_schedule	free	Validate a schedule and list the next 5 run times in UTC
create_cron	$0.008	Create a scheduled webhook job (includes 1 run credit)
topup_cron	$0.008–$0.80	Add 1, 10, or 100 prepaid run credits
get_cron	free	Job status, credits, last 20 executions
list_crons	free	Jobs created from this machine, with live status
pause_cron	free	Pause a job (EIP-712 signed)
resume_cron	free	Resume a paused job (requires credits)
delete_cron	free	Permanently delete a job (EIP-712 signed)

Paid tools handle x402 payment automatically. Management tools sign locally with your key.

Designed for weak models

• Plain-English schedules. "every 15 minutes", "every weekday at 9am", "every monday at 5pm", "weekly" and raw cron all work. Ambiguous or impossible phrases ("every 2 weeks", "at teatime") fail loudly with a fix, rather than silently scheduling the wrong thing.
• Timezones. Pass timezone: "America/New_York" and the time-of-day is converted to the UTC cron the API stores, with a DST caveat in the response.
• Free dry run. preview_schedule shows the next 5 fire times before a cent is spent, and create_cron re-validates locally so a bad schedule never costs money.
• Money guardrails. Paid tools say PAID in their descriptions, name the exact amount, and every response tells the model not to call them twice.
• Actionable errors. Insufficient funds, unreachable API, an unowned job or a localhost target each come back as { ok: false, error, next_step }.
• Job memory. Created job ids are written to ~/.cron402/jobs.json so list_crons can recover them — the API has no list endpoint.
• Starts without a key. A missing CRON402_PRIVATE_KEY degrades to read-only instead of failing to boot, so the model can explain what is missing.

Agent skill

A drop-in skill teaching an agent this whole workflow lives at skills/cron402/SKILL.md:

mkdir -p .claude/skills/cron402
curl -sL https://raw.githubusercontent.com/userdefault13/ai-cron-site/main/skills/cron402/SKILL.md \
  -o .claude/skills/cron402/SKILL.md

Links

• Integration docs
• OpenAPI spec
• Agent skill file
• Source
• MCP Registry

License

MIT