diff --git a/imperative/python/megengine/traced_module/pytree.py b/imperative/python/megengine/traced_module/pytree.py
index c55744e3fd2d9e5668c6c5b54854ca7dabca3a27..c4b132fab6f2a7c3e223ac1fcfefe4fd449ec3f5 100644
--- a/imperative/python/megengine/traced_module/pytree.py
+++ b/imperative/python/megengine/traced_module/pytree.py
@@ -10,7 +10,7 @@ import collections
 from collections import OrderedDict, defaultdict
 from functools import partial
 from inspect import FullArgSpec
-from typing import Any, Callable, List, NamedTuple, Tuple
+from typing import Any, Callable, Dict, List, NamedTuple, Tuple
 
 import numpy as np
 
@@ -284,8 +284,43 @@ class TreeDef:
             and self.children_defs == other.children_defs
         )
 
+    def _args_kwargs_repr(self):
+        if (
+            len(self.children_defs) == 2
+            and issubclass(self.children_defs[0].type, (List, Tuple))
+            and issubclass(self.children_defs[1].type, Dict)
+        ):
+            args_def = self.children_defs[0]
+            content = ", ".join(repr(i) for i in args_def.children_defs)
+            kwargs_def = self.children_defs[1]
+            if kwargs_def.aux_data:
+                content += ", "
+                content += ", ".join(
+                    str(i) + "=" + repr(j)
+                    for i, j in zip(kwargs_def.aux_data, kwargs_def.children_defs)
+                )
+            return content
+        else:
+            return repr(self)
+
     def __repr__(self):
-        return "{}[{}]".format(self.type.__name__, self.children_defs)
+        format_str = self.type.__name__ + "({})"
+        aux_data_delimiter = "="
+        if issubclass(self.type, List):
+            format_str = "[{}]"
+        if issubclass(self.type, Tuple):
+            format_str = "({})"
+        if issubclass(self.type, Dict):
+            format_str = "{{{}}}"
+            aux_data_delimiter = ":"
+        if self.aux_data:
+            content = ", ".join(
+                repr(i) + aux_data_delimiter + repr(j)
+                for i, j in zip(self.aux_data, self.children_defs)
+            )
+        else:
+            content = ", ".join(repr(i) for i in self.children_defs)
+        return format_str.format(content)
 
 
 class LeafDef(TreeDef):
@@ -315,6 +350,9 @@ class LeafDef(TreeDef):
         return hash(tuple([self.type, self.const_val]))
 
     def __repr__(self):
-        return "Leaf({}[{}])".format(
-            ", ".join(t.__name__ for t in self.type), self.const_val
+
+        return "{}".format(
+            self.const_val
+            if self.const_val is not None or type(None) in self.type
+            else self.type[0].__name__
         )
diff --git a/imperative/python/megengine/traced_module/traced_module.py b/imperative/python/megengine/traced_module/traced_module.py
index e22c818578a3f549555e10df503365214728e4f4..c4c25094cadf1c8862e69c4d172c61b1dec81056 100644
--- a/imperative/python/megengine/traced_module/traced_module.py
+++ b/imperative/python/megengine/traced_module/traced_module.py
@@ -1977,7 +1977,12 @@ class TracedModule(Module):
         if hasattr(self, "argspec") and self.argspec is not None:
             args, kwargs = _convert_kwargs_to_args(self.argspec, args, kwargs, True)
         inputs, treedef = tree_flatten(((self, *args), kwargs))
-        assert treedef in self.argdef_graph_map
+        assert (
+            treedef in self.argdef_graph_map
+        ), "support input args kwargs format: \n{}, but get: \n{}".format(
+            "\n ".join("forward({})".format(i._args_kwargs_repr()) for i in self.argdef_graph_map.keys()),
+            treedef._args_kwargs_repr(),
+        )
         inputs = filter(
             lambda i: isinstance(i, (Module, TracedModuleBuilder, RawTensor)), inputs
         )  # allow TracedModuleBuilder for retrace.