fix: preserve files during message summarization

lib/crewai/src/crewai/utilities/agent_utils.py

@@ -613,13 +613,23 @@ def summarize_messages(
 ) -> None:
     """Summarize messages to fit within context window.
 
+    Preserves any files attached to user messages and re-attaches them to
+    the summarized message. Files from all user messages are merged.
+
     Args:
-        messages: List of messages to summarize
+        messages: List of messages to summarize (modified in-place)
         llm: LLM instance for summarization
         callbacks: List of callbacks for LLM
         i18n: I18N instance for messages
     """
-    messages_string = " ".join([message["content"] for message in messages])  # type: ignore[misc]
+    preserved_files: dict[str, Any] = {}
+    for msg in messages:
+        if msg.get("role") == "user" and msg.get("files"):
+            preserved_files.update(msg["files"])
+
+    messages_string = " ".join(
+        [str(message.get("content", "")) for message in messages]
+    )
     cut_size = llm.get_context_window_size()
 
     messages_groups = [
@@ -636,7 +646,7 @@ def summarize_messages(
             color="yellow",
         )
 
-        messages = [
+        summarization_messages = [
             format_message_for_llm(
                 i18n.slice("summarizer_system_message"), role="system"
             ),
@@ -645,7 +655,7 @@ def summarize_messages(
             ),
         ]
         summary = llm.call(
-            messages,
+            summarization_messages,
             callbacks=callbacks,
         )
         summarized_contents.append({"content": str(summary)})
@@ -653,11 +663,12 @@ def summarize_messages(
     merged_summary = " ".join(content["content"] for content in summarized_contents)
 
     messages.clear()
-    messages.append(
-        format_message_for_llm(
-            i18n.slice("summary").format(merged_summary=merged_summary)
-        )
+    summary_message = format_message_for_llm(
+        i18n.slice("summary").format(merged_summary=merged_summary)
     )
+    if preserved_files:
+        summary_message["files"] = preserved_files
+    messages.append(summary_message)
 
 
 def show_agent_logs(
@@ -859,7 +870,11 @@ def extract_tool_call_info(
     if hasattr(tool_call, "function"):
         # OpenAI-style: has .function.name and .function.arguments
         call_id = getattr(tool_call, "id", f"call_{id(tool_call)}")
-        return call_id, sanitize_tool_name(tool_call.function.name), tool_call.function.arguments
+        return (
+            call_id,
+            sanitize_tool_name(tool_call.function.name),
+            tool_call.function.arguments,
+        )
     if hasattr(tool_call, "function_call") and tool_call.function_call:
         # Gemini-style: has .function_call.name and .function_call.args
         call_id = f"call_{id(tool_call)}"

lib/crewai/tests/utilities/test_agent_utils.py

@@ -3,11 +3,12 @@
 from __future__ import annotations
 
 from typing import Any
+from unittest.mock import MagicMock, patch
 
 from pydantic import BaseModel, Field
 
 from crewai.tools.base_tool import BaseTool
-from crewai.utilities.agent_utils import convert_tools_to_openai_schema
+from crewai.utilities.agent_utils import convert_tools_to_openai_schema, summarize_messages
 
 
 class CalculatorInput(BaseModel):
@@ -211,3 +212,136 @@ class TestConvertToolsToOpenaiSchema:
         # Default value should be preserved
         assert "default" in max_results_prop
         assert max_results_prop["default"] == 10
+
+
+class TestSummarizeMessages:
+    """Tests for summarize_messages function."""
+
+    def test_preserves_files_from_user_messages(self) -> None:
+        """Test that files attached to user messages are preserved after summarization."""
+        mock_files = {"image.png": MagicMock(), "doc.pdf": MagicMock()}
+        messages: list[dict[str, Any]] = [
+            {"role": "system", "content": "You are a helpful assistant."},
+            {"role": "user", "content": "Analyze this image", "files": mock_files},
+            {"role": "assistant", "content": "I can see the image shows..."},
+            {"role": "user", "content": "What about the colors?"},
+        ]
+
+        mock_llm = MagicMock()
+        mock_llm.get_context_window_size.return_value = 1000
+        mock_llm.call.return_value = "Summarized conversation about image analysis."
+
+        mock_i18n = MagicMock()
+        mock_i18n.slice.side_effect = lambda key: {
+            "summarizer_system_message": "Summarize the following.",
+            "summarize_instruction": "Summarize: {group}",
+            "summary": "Summary: {merged_summary}",
+        }.get(key, "")
+
+        summarize_messages(
+            messages=messages,
+            llm=mock_llm,
+            callbacks=[],
+            i18n=mock_i18n,
+        )
+
+        assert len(messages) == 1
+        assert messages[0]["role"] == "user"
+        assert "files" in messages[0]
+        assert messages[0]["files"] == mock_files
+
+    def test_merges_files_from_multiple_user_messages(self) -> None:
+        """Test that files from multiple user messages are merged."""
+        file1 = MagicMock()
+        file2 = MagicMock()
+        file3 = MagicMock()
+        messages: list[dict[str, Any]] = [
+            {"role": "user", "content": "First image", "files": {"img1.png": file1}},
+            {"role": "assistant", "content": "I see the first image."},
+            {"role": "user", "content": "Second image", "files": {"img2.png": file2, "doc.pdf": file3}},
+            {"role": "assistant", "content": "I see the second image and document."},
+        ]
+
+        mock_llm = MagicMock()
+        mock_llm.get_context_window_size.return_value = 1000
+        mock_llm.call.return_value = "Summarized conversation."
+
+        mock_i18n = MagicMock()
+        mock_i18n.slice.side_effect = lambda key: {
+            "summarizer_system_message": "Summarize the following.",
+            "summarize_instruction": "Summarize: {group}",
+            "summary": "Summary: {merged_summary}",
+        }.get(key, "")
+
+        summarize_messages(
+            messages=messages,
+            llm=mock_llm,
+            callbacks=[],
+            i18n=mock_i18n,
+        )
+
+        assert len(messages) == 1
+        assert "files" in messages[0]
+        assert messages[0]["files"] == {
+            "img1.png": file1,
+            "img2.png": file2,
+            "doc.pdf": file3,
+        }
+
+    def test_works_without_files(self) -> None:
+        """Test that summarization works when no files are attached."""
+        messages: list[dict[str, Any]] = [
+            {"role": "user", "content": "Hello"},
+            {"role": "assistant", "content": "Hi there!"},
+        ]
+
+        mock_llm = MagicMock()
+        mock_llm.get_context_window_size.return_value = 1000
+        mock_llm.call.return_value = "A greeting exchange."
+
+        mock_i18n = MagicMock()
+        mock_i18n.slice.side_effect = lambda key: {
+            "summarizer_system_message": "Summarize the following.",
+            "summarize_instruction": "Summarize: {group}",
+            "summary": "Summary: {merged_summary}",
+        }.get(key, "")
+
+        summarize_messages(
+            messages=messages,
+            llm=mock_llm,
+            callbacks=[],
+            i18n=mock_i18n,
+        )
+
+        assert len(messages) == 1
+        assert "files" not in messages[0]
+
+    def test_modifies_original_messages_list(self) -> None:
+        """Test that the original messages list is modified in-place."""
+        messages: list[dict[str, Any]] = [
+            {"role": "user", "content": "First message"},
+            {"role": "assistant", "content": "Response"},
+            {"role": "user", "content": "Second message"},
+        ]
+        original_list_id = id(messages)
+
+        mock_llm = MagicMock()
+        mock_llm.get_context_window_size.return_value = 1000
+        mock_llm.call.return_value = "Summary"
+
+        mock_i18n = MagicMock()
+        mock_i18n.slice.side_effect = lambda key: {
+            "summarizer_system_message": "Summarize.",
+            "summarize_instruction": "Summarize: {group}",
+            "summary": "Summary: {merged_summary}",
+        }.get(key, "")
+
+        summarize_messages(
+            messages=messages,
+            llm=mock_llm,
+            callbacks=[],
+            i18n=mock_i18n,
+        )
+
+        assert id(messages) == original_list_id
+        assert len(messages) == 1