> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.tiankii.com/api-reference/tiankii-api-api-key/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.tiankii.com/_mcp/server. # Overview Endpoints of the TK Merchant API that accept **API Key** authentication. Covers the **Checkout Invoice**, **Customers**, **Products** and **Payment Requests** (with its two active types: **Payment Links** and **Invoices**) modules. ## Configuration | | | | -------------------- | --------------------------------------------------------------------------------------------------------------------------- | | **Base URL** | `https://api.md.tiankii.com` | | **Auth header** | `x-api-key: {{api_key}}` (alias `x-account-api-key`) | | **Optional scoping** | `x-application-account-id` (alias `x-account-id`), also accepted as the `application_account_id` / `account_id` query param | Transaction endpoints additionally take `store_id`, `app_id`, and `pay_method_id` in the request body. > **Note** > > Don't have credentials yet? The [getting started guide](/docs) walks through creating your API key and finding your `store_id` and `app_id` in the merchant portal. ## Collection structure * **Checkout Invoice** — the Lightning/on-chain *charge* generated when someone pays. Not to be confused with the **Invoices** type of a payment request. * **Customers** — the merchant's clients; recipients of the invoices you issue. * **Products** — the catalog (products and their modifiers) the merchant sells at its places (apps / terminals). * **Payment Requests** — the aggregate used to collect payment. Every payment request has a `type`: * **Payment Links** (`PAYMENT_LINK`) — a hosted, shareable payment page. * **Invoices** (`INVOICE`) — a bill issued to a customer. Lifecycle and query operations (list, pay, activate, archive, complete, delete) are common to both types and live in the **General operations** subfolder. ## Docs - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/payment-links.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/invoices.md) - [Overview](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations.md) ## API Docs - TIANKII API - API Key > Checkout Invoice [List invoices](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/list.md) - TIANKII API - API Key > Checkout Invoice [Create invoice](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/create.md) - TIANKII API - API Key > Checkout Invoice [Get invoice](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/get.md) - TIANKII API - API Key > Checkout Invoice [Get invoice status](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/get-status.md) - TIANKII API - API Key > Checkout Invoice [Get checkout payload](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/get-checkout.md) - TIANKII API - API Key > Checkout Invoice [List invoice events](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/list-events.md) - TIANKII API - API Key > Checkout Invoice [Re-check invoice status](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/recheck.md) - TIANKII API - API Key > Checkout Invoice [Update payment method](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/update-payment-method.md) - TIANKII API - API Key > Checkout Invoice [Send paid notification](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/send-notification.md) - TIANKII API - API Key > Checkout Invoice [Reopen invoice](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/reopen.md) - TIANKII API - API Key > Checkout Invoice [Cancel invoice](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/cancel.md) - TIANKII API - API Key > Checkout Invoice [Mark as paid](https://docs.tiankii.com/api-reference/tiankii-api-api-key/invoice/mark-as-paid.md) - TIANKII API - API Key > Customers [List customers](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers/list.md) - TIANKII API - API Key > Customers [Create customer](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers/create.md) - TIANKII API - API Key > Customers [Get customer](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers/get.md) - TIANKII API - API Key > Customers [Delete customer](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers/delete.md) - TIANKII API - API Key > Customers [Update customer](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers/update.md) - TIANKII API - API Key > Customers [List customer invoices](https://docs.tiankii.com/api-reference/tiankii-api-api-key/customers/list-invoices.md) - TIANKII API - API Key > Products > Modifiers [List modifiers](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/list.md) - TIANKII API - API Key > Products > Modifiers [Create modifier](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/create.md) - TIANKII API - API Key > Products > Modifiers [Get modifier](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/get.md) - TIANKII API - API Key > Products > Modifiers [Replace modifier](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/replace.md) - TIANKII API - API Key > Products > Modifiers [Delete modifier](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/delete.md) - TIANKII API - API Key > Products > Modifiers [Link products to modifier](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/link-products.md) - TIANKII API - API Key > Products > Modifiers [List modifier products](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/modifiers/list-products.md) - TIANKII API - API Key > Products [List products](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/list.md) - TIANKII API - API Key > Products [Create product](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/create.md) - TIANKII API - API Key > Products [Get product](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/get.md) - TIANKII API - API Key > Products [Delete product](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/delete.md) - TIANKII API - API Key > Products [Update product](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/update.md) - TIANKII API - API Key > Products [List product modifiers](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/list-modifiers.md) - TIANKII API - API Key > Products [List product locations](https://docs.tiankii.com/api-reference/tiankii-api-api-key/products/list-locations.md) - TIANKII API - API Key > Payment Requests > Payment Links [Create payment link](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/payment-links/create.md) - TIANKII API - API Key > Payment Requests > Payment Links [Update payment link](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/payment-links/update.md) - TIANKII API - API Key > Payment Requests > Invoices [Create invoice](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/invoices/create.md) - TIANKII API - API Key > Payment Requests > Invoices [Update invoice](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/invoices/update.md) - TIANKII API - API Key > Payment Requests > Invoices [Send invoice by email](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/invoices/send.md) - TIANKII API - API Key > Payment Requests > Invoices [Download invoice PDF](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/invoices/download-pdf.md) - TIANKII API - API Key > Payment Requests > General Operations [List payment requests](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/list.md) - TIANKII API - API Key > Payment Requests > General Operations [List available apps](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/list-available-apps.md) - TIANKII API - API Key > Payment Requests > General Operations [Get associated app](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/get-app.md) - TIANKII API - API Key > Payment Requests > General Operations [List coupons](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/list-coupons.md) - TIANKII API - API Key > Payment Requests > General Operations [Activate payment request](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/activate.md) - TIANKII API - API Key > Payment Requests > General Operations [Deactivate payment request](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/deactivate.md) - TIANKII API - API Key > Payment Requests > General Operations [Archive payment request](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/archive.md) - TIANKII API - API Key > Payment Requests > General Operations [Complete payment request](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/complete.md) - TIANKII API - API Key > Payment Requests > General Operations [Delete payment request](https://docs.tiankii.com/api-reference/tiankii-api-api-key/payment-requests/general-operations/delete.md) ## OpenAPI Specification The raw OpenAPI 3.1 specification for this API is available at: - [OpenAPI JSON](https://docs.tiankii.com/api-reference/tiankii-api-api-key/openapi.json) - [OpenAPI YAML](https://docs.tiankii.com/api-reference/tiankii-api-api-key/openapi.yaml)