Add src/tools.py

src/tools.py

@@ -0,0 +1,36 @@
+"""MCP‑style tool that fetches course metadata from a local JSON file.
+
+The function `fetch_course_meta` performs a GET request to the mock MCP server
+and returns the JSON content.  It is wrapped with LangChain's `tool` decorator
+so that the agent can call it.
+"""
+
+import json
+from pathlib import Path
+from typing import Dict
+
+import httpx
+from langchain.tools import tool
+from .config import MCP_SERVER_URL
+
+@tool("fetch_course_meta")
+def fetch_course_meta(query: str) -> Dict:
+    """Return course metadata that matches *query*.
+
+    The mock server simply returns the full JSON; the agent decides whether
+    the query is about metadata.  The function is intentionally simple to
+    keep the focus on routing logic.
+    """
+    try:
+        response = httpx.get(MCP_SERVER_URL, timeout=5.0)
+        response.raise_for_status()
+        data = response.json()
+    except Exception as exc:  # pragma: no cover – network errors
+        raise RuntimeError(f"Failed to fetch metadata: {exc}")
+
+    # Basic filtering – return the whole object if the query contains a
+    # known keyword.  In a real system this would be more sophisticated.
+    if any(k.lower() in query.lower() for k in data.keys()):
+        return data
+    # If nothing matches, return an empty dict
+    return {"message": "No metadata found for the query."}