Your code approves every purchase
Before a purchase goes through, Guara asks your endpoint. Answer APPROVE or DECLINE within 1.2 seconds.
- 1.2 s window
- Fails closed
- Signed requests
Live in three steps.
- 0 msA purchase starts
Guara checks the card, limit and balance.
✓ card active✓ limit · balance - < 1,200 msYour code decides
A signed request to your endpoint.
⇢ authorization.request← APPROVE ✓ - AfterIt settles
The result reaches you by webhook.
⇢ transaction.posted ✓· paid from balance
Authorization, end to end.
Fail closed
No answer in 1,200 ms, or anything but APPROVE — the purchase is declined.
Checks in order
Card, limit, balance — then your endpoint.
Signed requests
Verify X-GuaraPay-Signature before you answer.
A reason with a decline
Send DECLINE with your reason code.
No endpoint needed
Without one, card state, limit and balance decide.
A few lines
to start.
Same REST API, same keys and limits for every program. Docs open in the console after sign-up.
# Guara → your endpoint, on every purchase POST /guara/authorize HTTP/1.1 X-GuaraPay-Signature: t=1762850000,v1=5f2c9e… { "type": "card.authorization.request", "data": { "card_id": "crd_8f3k…", "external_user_id": "user_42", "amount_cents": 12000, "currency": "USD", "merchant": "OpenAI" } } # your answer, within 1200 ms HTTP/1.1 200 OK { "decision": "APPROVE" }
Tell us what you're building.
Three steps from here to live cards.
- We reply within a business dayPricing for your volume, by email or your contact.
- You connect the APIKeys, webhooks and MCP for your agents.
- You go liveSwitch to live keys and issue cards to your users.
Authorization: FAQ
What is real-time (JIT) authorization?
Each purchase is sent to your endpoint before it is approved, so your own rules and ledger decide.
What if my endpoint is down?
No answer in 1.2 seconds — the purchase is declined.
What does Guara check before asking me?
The card state, its limit and the balance. If one of them fails, your endpoint is not asked.
Do I have to run an endpoint?
No. In the default mode the card state, limit and balance decide alone.