> For the complete documentation index, see [llms.txt](https://docs.apollopayment.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apollopayment.io/english-2/api-reference/01base_actions.md).

# Base actions

- [Check x-api-signature](https://docs.apollopayment.io/english-2/api-reference/01base_actions/post_test-signature.md)
- [Fetch available currencies](https://docs.apollopayment.io/english-2/api-reference/01base_actions/post_available-currencies.md)
- [Current price request](https://docs.apollopayment.io/english-2/api-reference/01base_actions/post_price-rate.md)
- [Search for operations by TX hash](https://docs.apollopayment.io/english-2/api-reference/01base_actions/post_find-tx.md)
- [Check address format](https://docs.apollopayment.io/english-2/api-reference/01base_actions/post_validate-address.md)
- [Get transaction history](https://docs.apollopayment.io/english-2/api-reference/01base_actions/post_get-transaction-history.md)