Thanks Rushabh for you feedback, I understand the stability of API, but because of my supply chain, this mechanism is the major form to automate te process and reduce the re-input.
Each supplier have a custom system to manage yours Purchase Requests, actualy our have 15 suppliers, if our re-input the data manually from my system to supplier Purchase Request system, the time elapsed in this works is very long, and have a big probality of error.
And more, my old system don't contains an API, because this the choice.