# SpendGate

> Score a planned spend before an autonomous agent pays. Verdicts are approve, ask_human, or block.

SpendGate is a decision check, not a wallet and not the payment itself. Call it before a tool moves money. The underlying merchant charge is still yours to make or refuse.

## When to use

- Before a crypto transfer, gift card, irreversible purchase, subscription, or paid API call.
- When a planner proposes a spend and you have a daily or monthly budget left. Pass that remaining budget. Over budget is a block.
- When the amount is under the free micro threshold (default $1) and you still want a recorded check. Those return approve unless they exceed a budget you supplied.
- Skip it for pure reads that do not spend. status_check is the low-risk category when you do call.

Do not reword purpose and retry to fish for approve. v1 scoring is deterministic.

## Verdicts

- approve: pay.
- ask_human: do not pay yet. Ask a person.
- block: do not pay.

## Free tier

- Anonymous: 100 scores per UTC day, no key.
- Free key: POST https://spendgate.toolweather.workers.dev/v1/keys, then Authorization: Bearer sg_live_…. 1000 scores per UTC day.
- Toolweather bundle proxy: a matching x-tw-bundle-secret charges x-tw-bundle-client. A hex client (Toolweather API key hash) gets the free-key cap (1000 scores per UTC day). An anonymous Toolweather caller whose client id starts with anon: gets the anonymous cap (100 scores per UTC day). get_quota still reports subject and tier bundle, with daily_limit set to that cap. A missing or wrong secret stays on the anonymous IP cap. An sg_live_ key still wins.
- After the cap, each score costs 0.001 USDC on Base (eip155:8453) via x402. Facilitator: https://facilitator.payai.network.
- get_quota, get_api_key, docs, and this file are not billed.
- Paid calls require PAY_TO on the server. If it is unset, over-cap scores return 402 payment_not_configured and do not invent a wallet.

## API

- [Score a spend](https://spendgate.toolweather.workers.dev/v1/score): POST JSON { amount, currency?, category?, purpose?, merchant?, agent_id?, daily_budget_remaining?, monthly_budget_remaining?, risk_hints? }
- [Quota](https://spendgate.toolweather.workers.dev/v1/quota): GET remaining free scores.
- [Mint a key](https://spendgate.toolweather.workers.dev/v1/keys): POST { label? }
- [Policy](https://spendgate.toolweather.workers.dev/v1/policy): GET the v1 formula.
- [OpenAPI](https://spendgate.toolweather.workers.dev/openapi.json)
- [MCP server card](https://spendgate.toolweather.workers.dev/.well-known/mcp)
- [x402 discovery](https://spendgate.toolweather.workers.dev/.well-known/x402)

## MCP

Endpoint: https://spendgate.toolweather.workers.dev/mcp (streamable HTTP, protocol 2025-06-18).

Tools: score_spend, get_quota, get_api_key.

## Categories

High risk: crypto_transfer, irreversible, gift_card.
Medium risk: api_call, saas, infra.
Low risk: status_check.
Anything else is unknown risk.

## Optional later

Free spend watches are not in v1.