diff --git a/polymind/core/agent.py b/polymind/core/agent.py
index eb6ab5e..450c901 100644
--- a/polymind/core/agent.py
+++ b/polymind/core/agent.py
@@ -81,5 +81,5 @@ async def __call__(self, input: Message) -> Message:
         """
         if not self.thought_process:
             raise ValueError("The thought process of the agent needs to be hooked first.")
-        self._input_preprocess(self, input)
-        return await self.thought_process(input)
+        self._input_preprocess(agent=self, input=input)
+        return await self.thought_process(agent=self, input=input)
diff --git a/pyproject.toml b/pyproject.toml
index 87deae6..4f165b5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "polymind"
-version = "0.0.20"  # Update this version before publishing to PyPI
+version = "0.0.21"  # Update this version before publishing to PyPI
 description = "PolyMind is a customizable collaborative multi-agent framework for collective intelligence and distributed problem solving."
 authors = ["TechTao"]
 license = "MIT License"