Create drugbank.py

mcp/drugbank.py

@@ -0,0 +1,28 @@
+# mcp/drugbank.py
+"""
+Lightweight DrugBank Open-Data helper.
+Download the TSV once and keep in /data or load at runtime.
+"""
+
+import csv
+from pathlib import Path
+from typing import Dict, Optional
+
+_DATA = Path(__file__).parent / "data" / "drugbank_open_structured_drug_links.tsv"
+
+def _load_index() -> Dict[str, Dict]:
+    index = {}
+    if not _DATA.exists():
+        raise FileNotFoundError("DrugBank TSV not found – download open data first.")
+    with _DATA.open() as f:
+        reader = csv.DictReader(f, delimiter="\t")
+        for row in reader:
+            name = row["Name"].lower()
+            index[name] = row
+    return index
+
+_DRUG_INDEX = _load_index()
+
+def lookup_drug(name: str) -> Optional[Dict]:
+    """Return DrugBank row dict or None."""
+    return _DRUG_INDEX.get(name.lower())