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

# Authentication

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Authentication is only setup for the subscription APIs.
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* All API requests require a valid `Authorization` token in the header.
* Tokens are JWT and must be signed with the corresponding secret key associated with your Flash account.