diff --git a/src/services/contacts_service.py b/src/services/contacts_service.py
index 0f3f568..69b0cfd 100644
--- a/src/services/contacts_service.py
+++ b/src/services/contacts_service.py
@@ -1,4 +1,5 @@
 from typing import Optional
+from urllib.parse import urlparse
 import uuid
 
 import httpx
@@ -51,6 +52,15 @@ class ContactsService:
             )
         return self._client
 
+    def _build_url(self, path: str) -> str:
+        """Build full URL from a path, handling both relative and absolute paths."""
+        if path.startswith("http://") or path.startswith("https://"):
+            return path
+        # Extract base URL (scheme + host) from carddav_url
+        parsed = urlparse(self.settings.carddav_url)
+        base = f"{parsed.scheme}://{parsed.netloc}"
+        return f"{base}{path}"
+
     def list_addressbooks(self) -> list[AddressBook]:
         client = self._get_client()
 
@@ -112,8 +122,7 @@ class ContactsService:
         client = self._get_client()
 
         # Build URL
-        base_url = self.settings.carddav_url.rstrip("/")
-        addressbook_url = f"{base_url}{addressbook_id}" if addressbook_id.startswith("/") else addressbook_id
+        addressbook_url = self._build_url(addressbook_id)
 
         response = client.request(
             "REPORT",
@@ -183,8 +192,7 @@ class ContactsService:
         client = self._get_client()
 
         # Build URL
-        base_url = self.settings.carddav_url.rstrip("/")
-        contact_url = f"{base_url}{contact_id}" if contact_id.startswith("/") else contact_id
+        contact_url = self._build_url(contact_id)
 
         response = client.get(contact_url)
 
@@ -275,8 +283,7 @@ class ContactsService:
                 adr.type_param = addr_data.get("type", "home").upper()
 
         # Build URL and save
-        base_url = self.settings.carddav_url.rstrip("/")
-        addressbook_url = f"{base_url}{addressbook_id}" if addressbook_id.startswith("/") else addressbook_id
+        addressbook_url = self._build_url(addressbook_id)
         contact_url = f"{addressbook_url.rstrip('/')}/{uid}.vcf"
 
         response = client.put(
@@ -343,8 +350,7 @@ class ContactsService:
             client = self._get_client()
 
             # Build URL
-            base_url = self.settings.carddav_url.rstrip("/")
-            contact_url = f"{base_url}{contact_id}" if contact_id.startswith("/") else contact_id
+            contact_url = self._build_url(contact_id)
 
             response = client.delete(contact_url)
 
diff --git a/test.sh b/test.sh
index 775194e..b12f919 100755
--- a/test.sh
+++ b/test.sh
@@ -74,10 +74,16 @@ echo -e "\n[6/7] Listing address books..."
 ADDRESSBOOKS=$(mcp_request 5 "tools/call" '{"name":"list_addressbooks","arguments":{}}')
 echo "$ADDRESSBOOKS"
 
-# List contacts
+# List contacts (using first addressbook from previous response)
 echo -e "\n[7/7] Listing contacts..."
-CONTACTS=$(mcp_request 6 "tools/call" '{"name":"list_contacts","arguments":{"limit":10}}')
-echo "$CONTACTS"
+# Extract first addressbook ID from previous response
+ADDRESSBOOK_ID=$(echo "$ADDRESSBOOKS" | grep -o '"id":"[^"]*"' | head -1 | cut -d'"' -f4)
+if [ -n "$ADDRESSBOOK_ID" ]; then
+    CONTACTS=$(mcp_request 6 "tools/call" "{\"name\":\"list_contacts\",\"arguments\":{\"addressbook_id\":\"$ADDRESSBOOK_ID\",\"limit\":10}}")
+    echo "$CONTACTS"
+else
+    echo "No addressbook found to list contacts from"
+fi
 
 echo -e "\n================================"
 echo "All tests completed!"