Update Python tools

python-tools/app/discovery.py

@@ -144,8 +144,14 @@ class TaskCatalog:
             group_path,
             {path.name for path in task_paths},
         )
+        paths_by_filename = {path.name: path for path in task_paths}
+        ordered_filenames = [
+            *declarations_by_filename,
+            *(path.name for path in task_paths if path.name not in declarations_by_filename),
+        ]
         tasks = []
-        for path in task_paths:
+        for filename in ordered_filenames:
+            path = paths_by_filename[filename]
             declaration = declarations_by_filename.get(path.name)
             tasks.append(
                 Task(
@@ -289,11 +295,10 @@ def parse_task_declaration(
 ) -> TaskDeclaration:
     if (
         not isinstance(declaration, dict)
-        or not {"inputs"} <= set(declaration)
         or set(declaration) - {"inputs", "wait_for_result", "download_artifacts"}
     ):
         raise ValueError(f"{manifest_path} task {filename} has an invalid declaration.")
-    raw_inputs = declaration["inputs"]
+    raw_inputs = declaration.get("inputs", [])
     if not isinstance(raw_inputs, list):
         raise ValueError(f"{manifest_path} task {filename} inputs must be a list.")
     fields = tuple(parse_input_field(manifest_path, filename, raw) for raw in raw_inputs)