added functionality to accept list content handling in bedrock cohere models

litellm/litellm_core_utils/prompt_templates/factory.py

@@ -2580,7 +2580,26 @@ def cohere_message_pt(messages: list):
             )
             tool_results.append(tool_result)
         elif message.get("content"):
-            prompt += message["content"] + "\n\n"
+            content = message["content"]
+
+            # Support both string content and OpenAI-style list-of-parts content
+            # e.g. [{"type": "text", "text": "Hi"}]
+            if isinstance(content, list):
+                text_parts: List[str] = []
+                for part in content:
+                    if isinstance(part, dict):
+                        # Prefer explicit text field
+                        if part.get("type") == "text" and "text" in part:
+                            text_parts.append(str(part["text"]))
+                        elif "text" in part:
+                            text_parts.append(str(part["text"]))
+                    elif isinstance(part, str):
+                        text_parts.append(part)
+
+                if len(text_parts) > 0:
+                    prompt += "".join(text_parts) + "\n\n"
+            else:
+                prompt += str(content) + "\n\n"
     prompt = prompt.rstrip()
     return prompt, tool_results
 

tests/test_litellm/litellm_core_utils/prompt_templates/test_cohere_message_pt.py

@@ -0,0 +1,32 @@
+import pytest
+
+from litellm.litellm_core_utils.prompt_templates.factory import cohere_message_pt
+
+
+def test_cohere_message_pt_with_string_content():
+    messages = [{"role": "user", "content": "Hi"}]
+
+    prompt, tool_results = cohere_message_pt(messages)
+
+    assert prompt == "Hi"
+    assert tool_results == []
+
+
+def test_cohere_message_pt_with_list_content_text_part():
+    messages = [
+        {
+            "role": "user",
+            "content": [
+                {
+                    "type": "text",
+                    "text": "Hi",
+                }
+            ],
+        }
+    ]
+
+    prompt, tool_results = cohere_message_pt(messages)
+
+    assert prompt == "Hi"
+    assert tool_results == []
+