Payroll Engine API

Idempotency

A timeout tells you nothing about whether the work happened. Send an Idempotency-Key on every mutating call and the retry is free: the engine returns the first response instead of acting twice.

bash

curl -X POST https://api.indpayroll.com/v1/payroll-runs/run_2026_09_0042/mark-paid \
  -H "Authorization: Bearer $INDP_API_KEY" \
  -H "Idempotency-Key: markpaid-run-2026-09-0042" \
  -H "Content-Type: application/json" \
  -d '{ "paid_on": "2026-10-05", "payment_method_id": 2 }'

The rules

Keys are scoped to the API key and remembered for 24 hours.
A replay within that window returns the original status and body, and changes nothing.
Reusing a key with a different body returns 409 idempotency_key_reused - it is a bug, not a retry.
Keys are at most 255 characters. Derive them from your own identifiers, not from a clock.

Where it matters mostcalculate, mark-paid, reverse and the FnF endpoints. A double calculation wastes a cycle; a double mark-paid corrupts what you tell your customer they disbursed.

GET requests need no key - they change nothing. PUT endpoints that replace a whole resource are already idempotent by shape, but a key still protects you from an interleaved retry landing after a later write.

Pagination and formats

Webhooks