### API Activation and Authentication

Source: https://app.buchhaltungsbutler.de/docs/api/v1/hc/de/articles/11468075328797-Einrichtung-der-API-Schnittstelle

Details on how to activate the API in your BuchhaltungsButler account and obtain the necessary API Client, API Secret, and API Key for authentication.

```APIDOC
## API Activation and Authentication

### Description
To activate the API, navigate to "Settings" → "Interfaces and API Access" in your BuchhaltungsButler account. Upon activation, you will find your API Client, API Secret, and API Key in the same location. These credentials are required for authenticating with the API.

For integration with authorized partner programs listed in BuchhaltungsButler, API access credentials are not needed. Instead, select and activate the partner service in "Settings" → "Interfaces and API Access". Your API Key will then be displayed for use with the partner service.

### Note on Partner Integrations
For specific integrations like GetMyInvoices, follow the setup instructions within "Settings" → "Document Transfer" under the "Document Transfer with GetMyInvoices" section.

### Authentication Parameters
- **API Client**: Your unique API client identifier.
- **API Secret**: Your secret key for authentication.
- **API Key**: A key for specific partner integrations or general use.
```

--------------------------------

### Testing the API with Postman

Source: https://app.buchhaltungsbutler.de/docs/api/v1/hc/de/articles/11468075328797-Einrichtung-der-API-Schnittstelle

Instructions on how to test the BuchhaltungsButler API using Postman, including setting up authentication and request headers.

```APIDOC
## Testing the API with Postman

### Description
This guide explains how to test the BuchhaltungsButler API using Postman. It covers setting up authentication (Basic Auth) and configuring request headers and body format.

### Setup Steps

1.  **Import Collection**: Download and import the provided Postman Collection for BuchhaltungsButler.
2.  **Configure Authorization**: 
    *   In Postman, edit the Collection.
    *   Navigate to the "Authorization" tab.
    *   Select "Basic Auth" from the dropdown.
    *   Enter your **API Client** in the "Username" field.
    *   Enter your **API Secret** in the "Password" field.
    *   Ensure "Inherit auth from parent" is enabled for individual requests within the collection.
3.  **Configure Headers**:
    *   Go to the "Headers" tab for a request.
    *   Add a new row with Key: `Content-Type` and Value: `application/json`.
4.  **Configure Request Body**:
    *   Go to the "Body" tab.
    *   Select "raw" from the dropdown.
    *   Choose "JSON" as the data format from the adjacent dropdown.
    *   Enter your API Key and define request parameters in the provided console.

### Note
Refer to the detailed API documentation for specific parameter requirements for each request.
```

--------------------------------

### Available API Endpoints Overview

Source: https://app.buchhaltungsbutler.de/docs/api/v1/hc/de/articles/11468075328797-Einrichtung-der-API-Schnittstelle

An overview of the functionalities provided by the BuchhaltungsButler API, categorized by module.

```APIDOC
## Available API Endpoints Overview

### Description
The BuchhaltungsButler API offers endpoints for various operations, including managing receipts, transactions, invoices, postings, settings, accounts, and comments.

### Endpoints

#### Receipts
- **Purpose**: Uploading and retrieving receipts and their associated information.

#### Transactions
- **Purpose**: Creating and retrieving payments, and assigning receipts to transactions.

#### Invoices
- **Purpose**: Creating invoices, quotations, and credit notes, including draft versions.

#### Postings
- **Purpose**: Adding and retrieving journal entries.

#### Settings
- **Purpose**: Adding debtor and creditor accounts.

#### Accounts
- **Purpose**: Querying existing base accounts.

#### Comments
- **Purpose**: Adding comments to receipts or payments.
```

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