Create targets.py

mcp/targets.py

@@ -0,0 +1,32 @@
+"""Open Targets GraphQL client – fetch gene ↔ disease ↔ drug associations.
+     Docs: https://platform.opentargets.org/
+     No API‑key required (public endpoint).
+"""
+
+import httpx, textwrap, asyncio
+from typing import List, Dict
+
+_OT_URL = "https://api.platform.opentargets.org/api/v4/graphql"
+
+_QUERY_TEMPLATE = textwrap.dedent(
+    """
+    query Assoc($gene: String!, $size: Int!) {
+      associations(geneSymbol: $gene, size: $size) {
+        rows {
+          score
+          datatypeId
+          datasourceId
+          disease { id name }
+          target  { id symbol }
+        }
+      }
+    }
+    """
+)
+
+async def fetch_ot_associations(gene_symbol: str, *, size: int = 30) -> List[Dict]:
+    payload = {"query": _QUERY_TEMPLATE, "variables": {"gene": gene_symbol, "size": size}}
+    async with httpx.AsyncClient(timeout=15) as client:
+        resp = await client.post(_OT_URL, json=payload)
+        resp.raise_for_status()
+        return resp.json()["data"]["associations"]["rows"]