diff --git a/lib/toolbox/cli/shell/cli_shell.c b/lib/toolbox/cli/shell/cli_shell.c
index daf5065ec..445a5f2aa 100644
--- a/lib/toolbox/cli/shell/cli_shell.c
+++ b/lib/toolbox/cli/shell/cli_shell.c
@@ -474,5 +474,6 @@ void cli_shell_join(CliShell* shell) {
 
 void cli_shell_set_prompt(CliShell* shell, const char* prompt) {
     furi_check(shell);
+    furi_check(furi_thread_get_state(shell->thread) == FuriThreadStateStopped);
     shell->prompt = prompt;
 }