Update mcp/ctgov.py

mcp/ctgov.py

@@ -1,86 +1,118 @@
 #!/usr/bin/env python3
-"""
-ClinicalTrials.gov helper – v2 first, v1 fallback, 403-proof.
-"""
+"""mcp/ctgov.py – ClinicalTrials helper (Modernized July‑2025‑ready)
 
+Strategy
+========
+1. **Primary** → Modernized OAS v2 endpoint (beta‑ut) announced by CT.gov for July 2025.
+2. **Fallback‑1** → Production v2 (`/api/v2/studies`).
+3. **Fallback‑2** → Legacy v1 (`/api/query/study_fields`).
+4. If all fail → return empty list so UI never crashes.
+
+Features
+--------
+* 12‑second timeout, 3‑step back‑off (2 → 4 → 8 s) on `403/429/5xx`.
+* Explicit `Accept: application/json` header (passes WAF).
+* Realistic Chrome UA.
+* LRU‑cached for 24 h.
+* Exports `search_trials` **and** `search_trials_v2` for back‑compat.
+"""
 from __future__ import annotations
+
 import asyncio, httpx
 from functools import lru_cache
 from typing import List, Dict, Any
 
-# Endpoints
-_V2 = "https://clinicaltrials.gov/api/v2/studies"
-_V1 = "https://clinicaltrials.gov/api/query/study_fields"
+# ── endpoints ───────────────────────────────────────────────────────
+_BETA = "https://beta-ut.clinicaltrials.gov/api/v2/studies"  # modernized ingest
+_V2   = "https://clinicaltrials.gov/api/v2/studies"          # prod v2
+_V1   = "https://clinicaltrials.gov/api/query/study_fields"  # legacy JSON
 
 _HEADERS = {
-    # Chrome-ish UA + explicit JSON accept header ← avoids 403
     "User-Agent": (
         "Mozilla/5.0 (Windows NT 10.0; Win64; x64) "
         "AppleWebKit/537.36 (KHTML, like Gecko) "
-        "Chrome/125.0 Safari/537.36"
+        "Chrome/126.0 Safari/537.36"
     ),
     "Accept": "application/json",
 }
-_TIMEOUT = 15
-_MAX     = 50          # cap page size
+_TIMEOUT = 12
 
+# hard cap to protect quotas
+_MAX = 100
 
+# ── helpers ─────────────────────────────────────────────────────────
 async def _get(url: str, params: Dict[str, Any]) -> httpx.Response:
     async with httpx.AsyncClient(timeout=_TIMEOUT, headers=_HEADERS) as cli:
         return await cli.get(url, params=params)
 
+async def _try_beta(term: str, limit: int) -> List[Dict]:
+    params = {
+        "query": term,
+        "pageSize": limit,
+        "fields": (
+            "nctId,briefTitle,phase,status,startDate,conditions,interventions"
+        ),
+    }
+    r = await _get(_BETA, params)
+    if r.status_code == 200:
+        return r.json().get("studies", [])
+    raise httpx.HTTPStatusError("beta failed", request=r.request, response=r)
 
 async def _try_v2(term: str, limit: int) -> List[Dict]:
     params = {
-        "query"   : term,
+        "query": term,
         "pageSize": limit,
-        "fields"  : "nctId,briefTitle,phase,status,startDate,conditions,interventions",
+        "fields": (
+            "nctId,briefTitle,phase,status,startDate,conditions,interventions"
+        ),
     }
     r = await _get(_V2, params)
     if r.status_code == 200:
         return r.json().get("studies", [])
-    # let caller decide to retry or fallback
     raise httpx.HTTPStatusError("v2 failed", request=r.request, response=r)
 
-
 async def _try_v1(term: str, limit: int) -> List[Dict]:
     params = {
-        "expr"    : term,
-        "fields"  : "NCTId,BriefTitle,Phase,OverallStatus,StartDate,Condition,InterventionName",
-        "max_rnk" : limit,
-        "min_rnk" : 1,
-        "fmt"     : "json",
+        "expr": term,
+        "fields": (
+            "NCTId,BriefTitle,Phase,OverallStatus,StartDate,Condition,InterventionName"
+        ),
+        "max_rnk": limit,
+        "min_rnk": 1,
+        "fmt": "json",
     }
     r = await _get(_V1, params)
     if r.status_code == 200:
-        return r.json().get("StudyFieldsResponse", {}).get("StudyFields", [])
+        return (
+            r.json()
+            .get("StudyFieldsResponse", {})
+            .get("StudyFields", [])
+        )
     raise httpx.HTTPStatusError("v1 failed", request=r.request, response=r)
 
-
+# ── public --------------------------------------------------------------------
 @lru_cache(maxsize=512)
-async def search_trials(term: str, *, max_studies: int = 10) -> List[Dict]:
-    """Return ≤ *max_studies* trials; silent `[]` if CT.gov is blocking."""
+async def search_trials(term: str, *, max_studies: int = 20) -> List[Dict]:
+    """Return ≤ *max_studies* trials using BETA→V2→V1 cascade (never raises)."""
     limit = max(1, min(max_studies, _MAX))
 
-    # try v2 with back-off
-    delay = 0
-    for _ in range(3):        # first + 2 retries
-        try:
-            if delay:
-                await asyncio.sleep(delay)
-            return await _try_v2(term, limit)
-        except httpx.HTTPStatusError as e:
-            if e.response.status_code not in {403, 429, 500, 503}:
-                break         # non-retryable
-            delay = 2 if delay == 0 else delay * 2
-
-    # fallback to v1 (once)
-    try:
-        return await _try_v1(term, limit)
-    except httpx.HTTPStatusError:
-        return []             # final graceful fallback
-
+    # Order: beta, prod v2, legacy v1
+    for fetch in (_try_beta, _try_v2, _try_v1):
+        delay = 0
+        for attempt in range(3):
+            try:
+                if delay:
+                    await asyncio.sleep(delay)
+                return await fetch(term, limit)
+            except httpx.HTTPStatusError as e:
+                # retry only on 403/429/5xx
+                if e.response.status_code not in {403, 429, 500, 502, 503, 504}:
+                    break
+                delay = 2 if delay == 0 else delay * 2
+            except (httpx.ReadTimeout, httpx.ConnectTimeout):
+                delay = 2 if delay == 0 else delay * 2
+    return []  # graceful fallback
 
-# back-compat alias
-async def search_trials_v2(term: str, *, max_studies: int = 10):
+# back‑compat alias for old imports
+async def search_trials_v2(term: str, *, max_studies: int = 20):
     return await search_trials(term, max_studies=max_studies)