fix: Alpaca intraday 503 — auto-select feed=iex for free plan

Free plan blocks SIP intraday data (403). IEX feed is free and real-time.
- _default_feed(): returns 'iex' for intraday timeframes, None for daily+
- get_bars() / get_multi_bars(): apply default feed automatically
- Callers can override with feed='sip' if on paid plan

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/services/alpaca_client.py

@@ -32,6 +32,19 @@ INTERVAL_MAP = {
 }
 
 
+_DAILY_TIMEFRAMES = {"1d", "1Day", "1w", "1Week", "1mo", "1Month"}
+
+
+def _default_feed(timeframe: str) -> Optional[str]:
+    """Return 'iex' for intraday timeframes (free plan), None for daily+.
+
+    Daily/weekly/monthly SIP data is accessible on the free plan.
+    Intraday SIP data requires a paid subscription — use IEX instead.
+    """
+    alpaca_tf = INTERVAL_MAP.get(timeframe, timeframe)
+    return None if alpaca_tf in _DAILY_TIMEFRAMES else "iex"
+
+
 def normalize_ticker(symbol: str) -> str:
     """Normalize ticker symbol for Alpaca API.
 
@@ -152,6 +165,7 @@ class AlpacaClient:
         start: Optional[str] = None,
         end: Optional[str] = None,
         limit: int = 10000,
+        feed: Optional[str] = None,
     ) -> List[Dict]:
         """
         Fetch bars for a single symbol with automatic pagination.
@@ -162,6 +176,8 @@ class AlpacaClient:
             start: RFC-3339 date/datetime (e.g. "2024-01-01")
             end: RFC-3339 date/datetime
             limit: Max bars per page (Alpaca max 10000)
+            feed: Data feed ("iex" = free real-time, "sip" = paid consolidated).
+                  Defaults to "iex" for intraday, no feed param for daily+.
 
         Returns:
             List of bar dicts with keys: t, o, h, l, c, v, n, vw
@@ -172,6 +188,10 @@ class AlpacaClient:
             params["start"] = start
         if end:
             params["end"] = end
+        # Default to iex feed for intraday intervals (free plan compatible)
+        effective_feed = feed or (_default_feed(timeframe))
+        if effective_feed:
+            params["feed"] = effective_feed
 
         all_bars: List[Dict] = []
         path = f"/v2/stocks/{normalize_ticker(symbol).upper()}/bars"
@@ -196,6 +216,7 @@ class AlpacaClient:
         end: Optional[str] = None,
         limit: int = 10000,
         batch_size: int = 200,
+        feed: Optional[str] = None,
     ) -> Dict[str, List[Dict]]:
         """
         Fetch bars for multiple symbols with auto-pagination and transparent batching.
@@ -222,6 +243,8 @@ class AlpacaClient:
         normalized = [normalize_ticker(s).upper() for s in symbols]
         result: Dict[str, List[Dict]] = {s: [] for s in normalized}
 
+        effective_feed = feed or _default_feed(timeframe)
+
         # Process in batches to stay within URL length limits
         for batch_start in range(0, len(normalized), batch_size):
             batch = normalized[batch_start: batch_start + batch_size]
@@ -234,6 +257,8 @@ class AlpacaClient:
                 params["start"] = start
             if end:
                 params["end"] = end
+            if effective_feed:
+                params["feed"] = effective_feed
 
             while True:
                 data = await self._request("GET", path, params=params)