Use empty string instead of 'No description available' for missing descriptions

src/serena/mcp.py

@@ -64,9 +64,11 @@ def make_tool(
     if docstring.description:
         func_doc = f"{docstring.description.strip().strip('.')}."
     else:
-        func_doc = "No description available."
+        func_doc = ""
     if (docstring.returns) and (docstring_returns := docstring.returns.description):
-        func_doc = f"{func_doc} Returns {docstring_returns.strip().strip('.')}."
+        # Only add a space before "Returns" if func_doc is not empty
+        prefix = " " if func_doc else ""
+        func_doc = f"{func_doc}{prefix}Returns {docstring_returns.strip().strip('.')}."
 
     # Parse the parameter descriptions from the docstring and add pass its description
     # to the parameters schema.

test/serena/test_mcp.py

@@ -218,7 +218,7 @@ def test_make_tool_missing_description() -> None:
     mcp_tool = make_tool(tool)
 
     assert mcp_tool.name == "no_description"
-    assert mcp_tool.description == "No description available. Returns A result."
+    assert mcp_tool.description == "Returns A result."
     assert mcp_tool.parameters["properties"]["param"]["description"] == "The parameter."
 
 

test_make_tool.py

@@ -0,0 +1,59 @@
+"""Simple test for the make_tool function."""
+
+import docstring_parser
+from typing import Any, Callable
+
+
+def make_tool_simplified(func_doc: str) -> str:
+    """Simplified version of make_tool function to test our fix."""
+    docstring = docstring_parser.parse(func_doc)
+
+    # Mount the tool description as a combination of the docstring description and
+    # the return value description, if it exists.
+    if docstring.description:
+        func_doc = f"{docstring.description.strip().strip('.')}."
+    else:
+        func_doc = ""
+    if (docstring.returns) and (docstring_returns := docstring.returns.description):
+        # Only add a space before "Returns" if func_doc is not empty
+        prefix = " " if func_doc else ""
+        func_doc = f"{func_doc}{prefix}Returns {docstring_returns.strip().strip('.')}."
+    
+    return func_doc
+
+
+def test_with_description():
+    """Test with a normal docstring that has a description."""
+    doc = """This is a test function.
+
+    :param name: The person's name
+    :param age: The person's age
+    :return: A greeting message
+    """
+    result = make_tool_simplified(doc)
+    assert result == "This is a test function. Returns A greeting message."
+
+
+def test_without_description():
+    """Test with a docstring that has no description."""
+    doc = """
+    :param name: The person's name
+    :param age: The person's age
+    :return: A greeting message
+    """
+    result = make_tool_simplified(doc)
+    assert result == "Returns A greeting message."
+
+
+def test_empty_docstring():
+    """Test with an empty docstring."""
+    doc = ""
+    result = make_tool_simplified(doc)
+    assert result == ""
+
+
+if __name__ == "__main__":
+    test_with_description()
+    test_without_description()
+    test_empty_docstring()
+    print("All tests passed!")