# PayCheck

> Deterministic trust score for a payee (domain, https URL, or 0x wallet) before an agent sends money. Part of the Toolweather suite. PayCheck does not send payments and does not hold wallet keys.

## When to use

Call PayCheck once per payee, immediately before a payment. Do not reword the purpose to fish for a better verdict. amount_usd and category are ignored.

## Endpoints

- [Policy v1](https://paycheck.toolweather.workers.dev/v1/policy): scoring rules, allowlist, denylist, quota, x402 price
- [OpenAPI](https://paycheck.toolweather.workers.dev/openapi.json): REST contract
- [MCP discovery](https://paycheck.toolweather.workers.dev/.well-known/mcp.json): streamable HTTP tools
- [x402 discovery](https://paycheck.toolweather.workers.dev/.well-known/x402): Base USDC overage price
- MCP: https://paycheck.toolweather.workers.dev/mcp (protocols 2025-06-18 and 2025-03-26)
- Check: POST https://paycheck.toolweather.workers.dev/v1/check
- Quota: GET https://paycheck.toolweather.workers.dev/v1/quota (free)
- Key: POST https://paycheck.toolweather.workers.dev/v1/keys (free, pc_live_…)

## Tools

- check_merchant: Check merchant
- get_quota: Get quota
- get_api_key: Get API key

## Free tier

- Anonymous: 100 checks / UTC day
- Free key or bundle hex client: 1,000 checks / UTC day
- Bundle anon: client: 100 checks / UTC day
- Over-cap check: $0.001 USDC on Base (eip155:8453) via x402
- get_quota, get_api_key, docs, and discovery are not billed

## Verdicts

trusted, unknown, suspicious, block. Trusted only for the published allowlist over https on port 443. Wallets are never trusted in v1 (no chain analysis).