> For the complete documentation index, see [llms.txt](https://developers.klasha.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.klasha.com/overview.md).

# Overview

- [Introduction](https://developers.klasha.com/overview/introduction.md)
- [Authentication](https://developers.klasha.com/overview/authentication.md): All our endpoints are secured and requests must be authenticated by passing your merchant public key or Bearer token in the request header.
- [Parameters](https://developers.klasha.com/overview/parameters.md): This page shows the list of template variables used across the documentation and their values.
- [Errors](https://developers.klasha.com/overview/errors.md)
- [Countries & Payment Methods](https://developers.klasha.com/overview/countries-and-payment-methods.md)