refactor(data): unify vendor errors under a VendorError hierarchy

Every condition where a vendor cannot return usable data now derives from a
single VendorError base (errors.py): NoMarketDataError, VendorRateLimitError,
and VendorNotConfiguredError (still a ValueError for back-compat). Vendor-named
errors subclass the generic bases, and the router catches the base types, so a
new vendor needs no new except clause. Not-configured now has explicit
try-next-vendor handling instead of falling through the generic catch-all. The
number of error types tracks the number of distinct router reactions, not the
number of causes.

tradingagents/dataflows/interface.py

@@ -1,35 +1,34 @@
 import logging
-from typing import Annotated
 
-# Import from vendor-specific modules
-from .y_finance import (
-    get_YFin_data_online,
-    get_stock_stats_indicators_window,
-    get_fundamentals as get_yfinance_fundamentals,
-    get_balance_sheet as get_yfinance_balance_sheet,
-    get_cashflow as get_yfinance_cashflow,
-    get_income_statement as get_yfinance_income_statement,
-    get_insider_transactions as get_yfinance_insider_transactions,
-)
-from .yfinance_news import get_news_yfinance, get_global_news_yfinance
 from .alpha_vantage import (
-    get_stock as get_alpha_vantage_stock,
-    get_indicator as get_alpha_vantage_indicator,
-    get_fundamentals as get_alpha_vantage_fundamentals,
     get_balance_sheet as get_alpha_vantage_balance_sheet,
     get_cashflow as get_alpha_vantage_cashflow,
+    get_fundamentals as get_alpha_vantage_fundamentals,
+    get_global_news as get_alpha_vantage_global_news,
     get_income_statement as get_alpha_vantage_income_statement,
+    get_indicator as get_alpha_vantage_indicator,
     get_insider_transactions as get_alpha_vantage_insider_transactions,
     get_news as get_alpha_vantage_news,
-    get_global_news as get_alpha_vantage_global_news,
+    get_stock as get_alpha_vantage_stock,
+)
+from .config import get_config
+from .errors import (
+    NoMarketDataError,
+    VendorNotConfiguredError,
+    VendorRateLimitError,
 )
-from .alpha_vantage_common import AlphaVantageRateLimitError
 from .fred import get_macro_data as get_fred_macro_data
 from .polymarket import get_prediction_markets as get_polymarket_prediction_markets
-from .symbol_utils import NoMarketDataError
-
-# Configuration and routing logic
-from .config import get_config
+from .y_finance import (
+    get_balance_sheet as get_yfinance_balance_sheet,
+    get_cashflow as get_yfinance_cashflow,
+    get_fundamentals as get_yfinance_fundamentals,
+    get_income_statement as get_yfinance_income_statement,
+    get_insider_transactions as get_yfinance_insider_transactions,
+    get_stock_stats_indicators_window,
+    get_YFin_data_online,
+)
+from .yfinance_news import get_global_news_yfinance, get_news_yfinance
 
 logger = logging.getLogger(__name__)
 
@@ -194,9 +193,14 @@ def route_to_vendor(method: str, *args, **kwargs):
 
         try:
             return impl_func(*args, **kwargs)
-        except AlphaVantageRateLimitError:
+        except VendorRateLimitError:
             logger.warning("Vendor %r rate-limited for %s; trying next vendor.", vendor, method)
             continue
+        except VendorNotConfiguredError as e:
+            logger.warning("Vendor %r not configured for %s; trying next vendor.", vendor, method)
+            if first_error is None:
+                first_error = e  # Surface it if no other vendor can serve the call.
+            continue
         except NoMarketDataError as e:
             last_no_data = e  # No data here; another configured vendor may have it
             continue
@@ -224,10 +228,14 @@ def route_to_vendor(method: str, *args, **kwargs):
         sym = last_no_data.symbol
         canonical = last_no_data.canonical
         resolved = "" if canonical == sym else f" (resolved to '{canonical}')"
+        # Surface the typed error's detail (e.g. "latest row is 2025-06-11 ...
+        # stale") so the agent sees the specific reason — invalid symbol, no
+        # coverage, or stale data — not just a generic "unavailable".
+        reason = f" ({last_no_data.detail})" if last_no_data.detail else ""
         return (
-            f"NO_DATA_AVAILABLE: No market data found for '{sym}'{resolved} from "
-            f"any configured vendor. The symbol may be invalid, delisted, or not "
-            f"covered by Yahoo Finance / Alpha Vantage. Do not estimate or "
+            f"NO_DATA_AVAILABLE: No usable market data for '{sym}'{resolved} from "
+            f"any configured vendor{reason}. The symbol may be invalid, delisted, "
+            f"not covered, or the vendor returned stale data. Do not estimate or "
             f"fabricate values — report that data is unavailable for this symbol."
         )
 
@@ -236,4 +244,4 @@ def route_to_vendor(method: str, *args, **kwargs):
     if first_error is not None:
         raise first_error
 
-    raise RuntimeError(f"No available vendor for '{method}'")
+    raise RuntimeError(f"No available vendor for '{method}'")