community[patch]: add args_schema to WikipediaQueryRun (#22019)

Description: This change adds args_schema (pydantic BaseModel) to
WikipediaQueryRun for correct schema formatting on LLM function calls

Issue: currently using WikipediaQueryRun with OpenAI function calling
returns the following error "TypeError: WikipediaQueryRun._run() got an
unexpected keyword argument '__arg1' ". This happens because the schema
sent to the LLM is "input: '{"__arg1":"Hunter x Hunter"}'" while the
method should be called with the "query" parameter.

---------

Co-authored-by: Bagatur <[email protected]>
Co-authored-by: Bagatur <[email protected]>

libs/community/langchain_community/tools/wikipedia/tool.py

@@ -1,13 +1,20 @@
 """Tool for the Wikipedia API."""
 
-from typing import Optional
+from typing import Optional, Type
 
 from langchain_core.callbacks import CallbackManagerForToolRun
+from langchain_core.pydantic_v1 import BaseModel, Field
 from langchain_core.tools import BaseTool
 
 from langchain_community.utilities.wikipedia import WikipediaAPIWrapper
 
 
+class WikipediaQueryInput(BaseModel):
+    """Input for the WikipediaQuery tool."""
+
+    query: str = Field(description="query to look up on wikipedia")
+
+
 class WikipediaQueryRun(BaseTool):
     """Tool that searches the Wikipedia API."""
 
@@ -20,6 +27,8 @@ class WikipediaQueryRun(BaseTool):
     )
     api_wrapper: WikipediaAPIWrapper
 
+    args_schema: Type[BaseModel] = WikipediaQueryInput
+
     def _run(
         self,
         query: str,