diff --git a/src/fellchensammlung/animal_shelter.py b/src/fellchensammlung/animal_shelter.py
index ad9ab5a..472a241 100644
--- a/src/fellchensammlung/animal_shelter.py
+++ b/src/fellchensammlung/animal_shelter.py
@@ -1,12 +1,40 @@
+import argparse
 import json
+import os
+
 import requests
 
-OSM_DATA_FILE = "osm_data.geojson"
-ENDPOINT = "https://test.notfellchen.org/api/organizations/"
-HEADERS = {
-    "Authorization": "API_KEY",
-    "Content-Type": "application/json"
-}
+DEFAULT_OSM_DATA_FILE = "osm_data.geojson"
+
+
+def parse_args():
+    """Parse command-line arguments."""
+    parser = argparse.ArgumentParser(description="Upload animal shelter data to the Notfellchen API.")
+    parser.add_argument("--api-token", type=str, help="API token for authentication.")
+    parser.add_argument("--instance", type=str, help="API instance URL.")
+    parser.add_argument("--data-file", type=str, help="Path to the GeoJSON file containing (only) animal shelters.")
+    return parser.parse_args()
+
+
+def get_config():
+    """Get configuration from environment variables or command-line arguments."""
+    args = parse_args()
+
+    api_token = args.api_token or os.getenv("NOTFELLCHEN_API_TOKEN")
+    instance = args.instance or os.getenv("NOTFELLCHEN_INSTANCE")
+    data_file = args.data_file or os.getenv("NOTFELLCHEN_DATA_FILE", DEFAULT_OSM_DATA_FILE)
+
+    if not api_token or not instance:
+        raise ValueError("API token and instance URL must be provided via environment variables or CLI arguments.")
+
+    return api_token, instance, data_file
+
+
+def load_osm_data(file_path):
+    """Load OSM data from a GeoJSON file."""
+    with open(file_path, "r", encoding="utf-8") as file:
+        data = json.load(file)
+    return data
 
 
 def load_osm_data(file_path):
@@ -33,9 +61,9 @@ def transform_osm_data(feature):
     }
 
 
-def send_to_api(data):
+def send_to_api(data, endpoint, headers):
     # Send transformed data to the Notfellchen API.
-    response = requests.post(ENDPOINT, headers=HEADERS, json=data)
+    response = requests.post(endpoint, headers=headers, json=data)
     if response.status_code == 201:
         print(f"Success: Shelter '{data['name']}' uploaded.")
     elif response.status_code == 400:
@@ -46,13 +74,24 @@ def send_to_api(data):
 
 
 def main():
+    # Get configuration
+    api_token, instance, data_file = get_config()
+
+    # Set headers and endpoint
+    endpoint = f"{instance}/api/organizations/"
+    headers = {
+        "Authorization": f"Token {api_token}",
+        "Content-Type": "application/json"
+    }
+
     # Step 1: Load OSM data
-    osm_data = load_osm_data(OSM_DATA_FILE)
+    osm_data = load_osm_data(data_file)
 
     # Step 2: Process each shelter and send it to the API
     for feature in osm_data.get("features", []):
         shelter_data = transform_osm_data(feature)
-        send_to_api(shelter_data)
+        send_to_api(shelter_data, endpoint, headers)
+
 
 if __name__ == "__main__":
     main()