vat-calculator

The GitHub page [1] of the project this API is based on says it is required for calculating tax when selling in one's own country. I don't know in which exact case though. [1]: https://github.com/mpociot/vat-calculator

The data for the API comes from the most widely used open source library on the subject [1]. It has 418 stars, is used by lots of people and is continually receiving pull requests / input from users. I bet you that it is not easy to find another entity (be it a person, an organisation or a piece of software) that knows as much about the problem. Of course, you are right about liability. You can sue your accountant. But I assume it will be more difficult for an open source project. [1]: https://github.com/mpociot/vat-calculator

> So why ask for the country of the seller in the API? I must admit I'm not 100% sure either. I'm just exposing the API of the underlying open source project which says to supply the seller's country [1]. [1]: https://github.com/mpociot/vat-calculator At the bottom, where it says "Important"

I did read the full page. You linked to https://github.com/mpociot/vat-calculator, which appears to be another unofficial third-party source. I mean no disrespect, but you're asking anyone relying on your API to trust you with their business. If you or anyone you rely on makes a mistake then your user will probably be breaking the law and on the hook for any missing tax. Moreover, by the nature of this system, the damage could be done in real time before any human reviews and approves any changes to what the customer's business is charging. I don't think it's unreasonable to want more information than you (or your immediate source) currently provide before giving that level of trust in this situation.