Lesson 4 — Force outcomes with magic values

Tests must be deterministic. In test mode, magic values are fixed inputs

that force a specific outcome — no real money, no real rails, no flaky tests.

The cheatsheet

Input	Outcome
`reference: "test_success"` or amount `1`	`succeeded`
`reference: "test_fail"` or amount `2`	`failed`
`reference: "test_pending"`	`processing`, then succeeds on the next simulate
any other reference/amount	`succeeded`
MyCash OTP `000000`	fails with `otp_incorrect` (any other OTP approves)
MyCash mobile `+679 999 7888`	rejected (`invalid_mobile`)
bank account ending `0000`	disbursement bounces

Simulate from anywhere

You can drive an intent to its forced outcome without a redirect — useful in

CI. Either call the endpoint directly:


curl -X POST https://api.transxact.io/simulate/pi_...

or use the one-click Simulate box in the magic-values card of the

Developer section.

A deterministic test loop


# always succeeds
curl https://api.transxact.io/payment-intents \
  -H "Authorization: Bearer sk_test_..." \
  -H "Content-Type: application/json" \
  -d '{ "amount": 100, "reference": "test_success" }'

curl -X POST https://api.transxact.io/simulate/pi_...
# → { "intent": { "status": "succeeded", ... } }

The same pattern with test_fail exercises your failure path: mark the order

failed, notify the customer, release stock.