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

# APIs

- [Overview](https://docs.nexusglobalpayments.org/apis/overview.md)
- [Payment Setup API flows](https://docs.nexusglobalpayments.org/apis/payment-setup-api-flows.md)
- [Countries](https://docs.nexusglobalpayments.org/apis/countries.md)
- [Address Types and Inputs](https://docs.nexusglobalpayments.org/apis/address-types-and-inputs.md)
- [Financial Institutions](https://docs.nexusglobalpayments.org/apis/financial-institutions.md)
- [Fees and Amounts](https://docs.nexusglobalpayments.org/apis/fees-and-amounts.md)
- [Quotes](https://docs.nexusglobalpayments.org/apis/quotes.md)
- [ISO 20022 Messages](https://docs.nexusglobalpayments.org/apis/iso-20022-messages.md)
- [FXP Rates](https://docs.nexusglobalpayments.org/apis/fxp-rates.md): APIs for FX Providers (FXPs) to create, retrieve and withdraw the exchange rates they offer on Nexus for quote generation.
- [FXP Tier-based Improvement](https://docs.nexusglobalpayments.org/apis/fxp-tier-based-improvement.md): APIs for FX Providers (FXPs) to manage improvement tiers, which give better rates in basis points for transactions at or above a threshold in a given source currency.
- [Additional optional APIs](https://docs.nexusglobalpayments.org/apis/additional-optional-apis.md)