diff --git a/langchain/prompts/base.py b/langchain/prompts/base.py
index c8d9c0f9..08b6ceca 100644
--- a/langchain/prompts/base.py
+++ b/langchain/prompts/base.py
@@ -1,6 +1,7 @@
 """BasePrompt schema definition."""
 from abc import ABC, abstractmethod
-from typing import Any, List
+from typing import Any, List, Union, Dict
+from pydantic import BaseModel, Field
 
 from langchain.formatting import formatter
 
@@ -41,11 +42,14 @@ class DefaultParser(OutputParser):
         """Parse the output of an LLM call."""
         return text
 
-class BasePromptTemplate(ABC):
+
+class BasePromptTemplate(BaseModel, ABC):
     """Base prompt should expose the format method, returning a prompt."""
 
     input_variables: List[str]
     """A list of the names of the variables the prompt template expects."""
+    output_parser: OutputParser = Field(default_factory=DefaultParser)
+    """How to parse the output of calling an LLM on this formatted prompt."""
 
     @abstractmethod
     def format(self, **kwargs: Any) -> str: