diff --git a/user-side-compiler/error-handling.lisp b/user-side-compiler/error-handling.lisp
index 9e7a36e..ca3e96e 100644
--- a/user-side-compiler/error-handling.lisp
+++ b/user-side-compiler/error-handling.lisp
@@ -41,7 +41,7 @@
   ((%context-string :initform "Tokenizing error:")))
 
 (define-condition missing-function-error (usc-error)
-  ((%context-string :initform "Non-existent function (TODO nicer error for this):")))
+  ((%context-string :initform "Couldn't find built-in function:")))
 
 (define-condition parser-error (usc-error)
   ((%context-string :initform "Syntax error:")))