diff --git a/src/app/api/markets/binance.py b/src/app/api/markets/binance.py
index f2b1ce8..4d892e5 100644
--- a/src/app/api/markets/binance.py
+++ b/src/app/api/markets/binance.py
@@ -57,7 +57,7 @@ class BinanceWrapper(MarketWrapper):
         """
         Formatta l'asset_id nel formato richiesto da Binance.
         """
-        i = asset_id.index('-')
+        i = asset_id.find('-')
         if i != -1: asset_id = asset_id[:i]
         return f"{asset_id}{self.currency}" if self.currency not in asset_id else asset_id
 
diff --git a/src/app/api/markets/coinbase.py b/src/app/api/markets/coinbase.py
index 2397e38..0115238 100644
--- a/src/app/api/markets/coinbase.py
+++ b/src/app/api/markets/coinbase.py
@@ -61,7 +61,7 @@ class CoinBaseWrapper(MarketWrapper):
         )
 
     def __format(self, asset_id: str) -> str:
-        i = asset_id.index('-')
+        i = asset_id.find('-')
         if i != -1: asset_id = asset_id[:i]
         return f"{asset_id}-{self.currency}"
 
diff --git a/src/app/api/markets/yfinance.py b/src/app/api/markets/yfinance.py
index 4a5e889..23964d0 100644
--- a/src/app/api/markets/yfinance.py
+++ b/src/app/api/markets/yfinance.py
@@ -47,7 +47,7 @@ class YFinanceWrapper(MarketWrapper):
         Formatta il simbolo per yfinance.
         Per crypto, aggiunge '-' e la valuta (es. BTC -> BTC-USD).
         """
-        i = asset_id.index('-')
+        i = asset_id.find('-')
         if i != -1: asset_id = asset_id[:i]
         return f"{asset_id}-{self.currency}"
 
diff --git a/src/app/api/tools/symbols_tool.py b/src/app/api/tools/symbols_tool.py
index 60e3ebf..90cee7e 100644
--- a/src/app/api/tools/symbols_tool.py
+++ b/src/app/api/tools/symbols_tool.py
@@ -44,7 +44,7 @@ class CryptoSymbolsTools(Toolkit):
         Args:
             query (str): Query di ricerca.
         Returns:
-            list[str]: Lista di simboli che contengono la query.
+            list[tuple[str, str]]: Lista di tuple (simbolo, nome) che contengono la query.
         """
         query_lower = query.lower()
         positions = self.final_table['Name'].str.lower().str.contains(query_lower)
@@ -59,7 +59,7 @@ class CryptoSymbolsTools(Toolkit):
         if not force_refresh and not self.final_table.empty:
             return
 
-        num_currencies = 250 # It looks like is the max per page otherwise yahoo returns 26
+        num_currencies = 250 # It looks like this is the max per page otherwise yahoo returns 26
         offset = 0
         stop = not self.final_table.empty
         table = self.final_table.copy()