diff --git a/aleph_alpha_client/document.py b/aleph_alpha_client/document.py
index 2afe14a..434f64b 100644
--- a/aleph_alpha_client/document.py
+++ b/aleph_alpha_client/document.py
@@ -1,7 +1,7 @@
 import base64
 from typing import Any, Dict, Optional, Sequence, Union
 
-from aleph_alpha_client.prompt import Image, Prompt, PromptItem, Text, _to_json
+from aleph_alpha_client.prompt import Image, Prompt, PromptItem, Text, Tokens, _to_json
 
 
 class Document:
@@ -12,7 +12,7 @@ class Document:
     def __init__(
         self,
         docx: Optional[str] = None,
-        prompt: Optional[Prompt] = None,
+        prompt: Optional[Sequence[Union[str, Text, Image, Tokens]]] = None,
         text: Optional[str] = None,
     ):
         # We use a base_64 representation for docx documents, because we want to embed the file
@@ -43,11 +43,14 @@ def from_docx_file(cls, path: str):
         return cls.from_docx_bytes(docx_bytes)
 
     @classmethod
-    def from_prompt(cls, prompt: Prompt):
+    def from_prompt(cls, prompt: Union[Prompt, Sequence[Union[str, Image]]]):
         """
         Pass a prompt that can contain multiple strings and Image prompts and prepare it to be used as a document
         """
-        return cls(prompt=prompt)
+        if isinstance(prompt, Prompt):
+            return cls(prompt=prompt.items)
+        else:
+            return cls(prompt=prompt)
 
     @classmethod
     def from_text(cls, text: str):
@@ -65,6 +68,11 @@ def _to_serializable_document(self) -> Dict[str, Any]:
         A dict if serialized to JSON is suitable as a document element
         """
 
+        def to_prompt_item(item: Union[str, Image, Text, Tokens]) -> PromptItem:
+            # document still uses a plain piece of text for text-prompts
+            # -> convert to Text-instance
+            return Text.from_text(item) if isinstance(item, str) else item
+
         if self.docx is not None:
             # Serialize docx to Document JSON format
             return {
@@ -72,7 +80,9 @@ def _to_serializable_document(self) -> Dict[str, Any]:
             }
         elif self.prompt is not None:
             # Serialize prompt to Document JSON format
-            prompt_data = [_to_json(prompt_item) for prompt_item in self.prompt.items]
+            prompt_data = [
+                _to_json(to_prompt_item(prompt_item)) for prompt_item in self.prompt
+            ]
             return {"prompt": prompt_data}
         elif self.text is not None:
             return {
diff --git a/tests/test_summarize.py b/tests/test_summarize.py
index eda9317..30ca19c 100644
--- a/tests/test_summarize.py
+++ b/tests/test_summarize.py
@@ -29,7 +29,7 @@ async def test_can_summarize_with_async_client(async_client: AsyncClient):
 def test_summarize(sync_client: Client):
     # when posting a Summarization request
     request = SummarizationRequest(
-        document=Document.from_prompt(Prompt.from_text("Andreas likes pizza.")),
+        document=Document.from_prompt(["Andreas likes pizza."]),
     )
 
     response = sync_client.summarize(request)