Update tools.py

tools.py

@@ -1,5 +1,6 @@
 from langchain_core.tools import tool
 from langchain_community.tools.tavily_search import TavilySearchResults
+from youtube_transcript_api import YouTubeTranscriptApi
 
 @tool
 def add(a: int, b: int) -> int:
@@ -59,4 +60,24 @@ def web_search(query: str) -> str:
             f'<Document source="{doc.metadata["source"]}" page="{doc.metadata.get("page", "")}"/>\n{doc.page_content}\n</Document>'
             for doc in search_docs
         ])
-    return {"web_results": formatted_search_docs}
+    return {"web_results": formatted_search_docs}
+
+@tool
+def fetch_youtube_transcript(video_url: str) -> str:
+    """
+    Fetch transcript of a YouTube video by URL.
+    Returns plain text if transcript is available.
+    """
+    import re
+    video_id_match = re.search(r"(?:v=|youtu\.be/)([\w-]+)", video_url)
+    if not video_id_match:
+        return "Invalid YouTube URL."
+
+    video_id = video_id_match.group(1)
+
+    try:
+        transcript_list = YouTubeTranscriptApi.get_transcript(video_id, languages=['en'])
+        transcript_text = " ".join([entry['text'] for entry in transcript_list])
+        return transcript_text[:4000]  # Limit to fit into context window
+    except Exception as e:
+        return f"Transcript not available or error: {str(e)}"