Discounts
Fixed or percentage offers, eligibility rules, limits, stacking, and atomic redemption.
Promotions are infrastructure.Treat them like it.
Run vouchers, gift cards, loyalty, and referrals behind one typed API. OfferKit is MIT-licensed, agent-ready, and yours to deploy.
Promotion graphLive checkout
OperationalIncoming checkoutSUMMER10$129.00 order
OKOfferKitevaluate()
Discount− $12.90
Gift cardBalance checked
Loyalty+116 points
ReferralReward queued
✓redemption.accepted42 ms · order_1042200 OK
✓
REST API
OpenAPI 3.1 from the live contract
✓
TypeScript SDK
Types without a codegen step
✓
CLI
Back-office actions from the terminal
✓
MCP server
Agent tools with explicit risk metadata
One model for every incentive.
Replace scattered checkout conditionals and one-off admin tools with a system your team can inspect, test, and operate.
Gift cards
Stored balances with partial spend, an immutable ledger, expiration, and rollback safety.
Loyalty
Programs, tiers, earning rules, rewards, member ledgers, and points expiration.
Referrals
Stable referral codes, idempotent conversion, and configurable rewards for both sides.
Own the hot path.
Checkout logic needs clear outcomes under retries, concurrency, and partial failure. OfferKit makes those constraints part of the contract.
Read the API conventionsPOST
/api/v1/vouchers/SUMMER10/validateconst preview = await offerkit.vouchers.validate({
code: "SUMMER10",
order: { amount: 9999, currency: "USD" },
});voucher.eligible200 OK
- Rules evaluated
- No state changed
- Reason included
POST
/api/v1/vouchers/SUMMER10/redemptionconst result = await offerkit.vouchers.redeem({
code: "SUMMER10",
order: { amount: 9999, currency: "USD" },
idempotencyKey: "order-42",
});redemption.accepted200 OK
- Idempotent
- Balance committed
- Event emitted
POST
/api/v1/vouchers/WELCOME/explainconst decision = await offerkit.vouchers.explain({
code: "WELCOME",
customerId: "cus_88",
order: { amount: 2400, currency: "USD" },
});voucher.ineligibleMINIMUM_NOT_MET
- Typed reason
- Safe for support
- Rule identified
GET
/api/v1/events?subject=order-42const events = await offerkit.events.list({
subject: "order-42",
types: ["redemption.accepted"],
});webhook.deliveredSIGNED
- Audit linked
- Webhook verified
- Trace available
Your promotions. Your data. Your infrastructure.
Start locally, keep the contract stable, and deploy OfferKit wherever your stack runs.