Contract 規則範例

硬上限（Hard cap）

- id: hard-cap-stop
  when:
    budget_id: <uuid>
    claim_amount_atomic_gt: "1000000000"
  then:
    decision: STOP
    reason_code: BUDGET_EXHAUSTED

超過門檻就走核可流程

- id: large-spend-approval
  when:
    budget_id: <uuid>
    claim_amount_atomic_gte: "100000000"   # $100 in micro-USD if budget is USD
  then:
    decision: REQUIRE_APPROVAL
    reason_code: AMOUNT_OVER_THRESHOLD
    approver_role: tenant-admin

各 provider 個別 DENY（佔位用；要等規則 taxonomy 擴充）

# Future syntax — POC doesn't yet support context fields beyond claim
# amount and budget_id. Tracked in the v1 spec.

目前先把各 provider 的規則放在 application 邊界處理（讓 Pydantic-AI 的 claim_estimator 依不同 provider 回傳不同的 unit_id）。 詳見 pricing-and-usd。