diff --git a/src/symbols.py b/src/symbols.py
index 070b2c1c8666375360ccf58822753ff1cf9bff21..ce6da7a567baf6d2eb285a28c71688b0eda175c1 100644
--- a/src/symbols.py
+++ b/src/symbols.py
@@ -41,4 +41,4 @@ MORSE_SYMBOL_TO_LETTER: dict[str, str] = {
 
 
 class InvalidSymbolError(Exception):
-    pass
+    """To be raised if a morse symbol is provided that is invalid."""