diff --git a/app/services/monitoring.py b/app/services/monitoring.py
index 9ea73e5..9aeb4b3 100644
--- a/app/services/monitoring.py
+++ b/app/services/monitoring.py
@@ -1,6 +1,6 @@
 import json
 from datetime import datetime, timedelta, timezone
-from typing import Any, Dict
+from typing import Any, Dict, Tuple
 
 import requests
 from sqlalchemy.orm import Session
@@ -66,21 +66,69 @@ def test_provider_connection(provider: str, credential: str):
         return False, str(e)
 
 
+def _openai_usage(credential: str) -> Tuple[str, Dict[str, Any]]:
+    # Uses legacy billing endpoints; may be disabled in some orgs.
+    headers = _provider_headers('openai', credential)
+    today = _now().date()
+    start = (today - timedelta(days=7)).isoformat()
+    end = today.isoformat()
+    usage_url = f'https://api.openai.com/v1/dashboard/billing/usage?start_date={start}&end_date={end}'
+    sub_url = 'https://api.openai.com/v1/dashboard/billing/subscription'
+    u = requests.get(usage_url, headers=headers, timeout=12)
+    s = requests.get(sub_url, headers=headers, timeout=12)
+    if u.status_code != 200 or s.status_code != 200:
+        return 'error', {'error': f'usage:{u.status_code}, subscription:{s.status_code}'}
+    usage = u.json()
+    sub = s.json()
+    total_usage = usage.get('total_usage')
+    hard_limit = sub.get('hard_limit_usd')
+    reset_at = sub.get('billing_cycle_anchor')
+    if reset_at:
+        reset_at = datetime.fromtimestamp(reset_at, tz=timezone.utc).isoformat()
+    usage_pct = None
+    if total_usage is not None and hard_limit:
+        usage_pct = round(total_usage / hard_limit * 100, 2)
+    return 'ok', {
+        'window_label': '7d',
+        'used': total_usage,
+        'limit': hard_limit,
+        'usage_pct': usage_pct,
+        'reset_at': reset_at,
+        'raw': {'usage': usage, 'subscription': sub},
+    }
+
+
+def _anthropic_usage(credential: str) -> Tuple[str, Dict[str, Any]]:
+    # Anthropic usage endpoints are enterprise-specific; keep placeholder.
+    # We return accepted status; detail will be filled once API confirmed.
+    return 'unsupported', {'error': 'anthropic usage API not configured'}
+
+
 def refresh_provider_usage_once(db: Session):
     accounts = db.query(ProviderAccount).filter(ProviderAccount.is_enabled == True).all()
     now = _now()
     for a in accounts:
-        ok, msg = test_provider_connection(a.provider, a.credential)
+        status = 'pending'
+        payload: Dict[str, Any] = {}
+        if a.provider == 'openai':
+            status, payload = _openai_usage(a.credential)
+        elif a.provider == 'anthropic':
+            status, payload = _anthropic_usage(a.credential)
+        else:
+            ok, msg = test_provider_connection(a.provider, a.credential)
+            status = 'ok' if ok else 'error'
+            payload = {'error': None if ok else msg}
+
         snap = ProviderUsageSnapshot(
             account_id=a.id,
-            window_label='provider-default',
-            used=None,
-            limit=None,
-            usage_pct=None,
-            reset_at=None,
-            status='ok' if ok else 'error',
-            error=None if ok else msg,
-            raw_payload=json.dumps({'message': msg}, ensure_ascii=False),
+            window_label=payload.get('window_label'),
+            used=payload.get('used'),
+            limit=payload.get('limit'),
+            usage_pct=payload.get('usage_pct'),
+            reset_at=payload.get('reset_at'),
+            status=status,
+            error=payload.get('error'),
+            raw_payload=json.dumps(payload.get('raw') or payload, ensure_ascii=False),
             fetched_at=now,
         )
         db.add(snap)
@@ -100,7 +148,7 @@ def get_provider_usage_view(db: Session):
             'usage_pct': snap.usage_pct if snap else None,
             'used': snap.used if snap else None,
             'limit': snap.limit if snap else None,
-            'reset_at': snap.reset_at.isoformat() if snap and snap.reset_at else None,
+            'reset_at': snap.reset_at if snap else None,
             'status': snap.status if snap else 'pending',
             'error': snap.error if snap else None,
             'fetched_at': snap.fetched_at.isoformat() if snap and snap.fetched_at else None,