diff --git a/tools/cli/bash.go b/tools/cli/bash.go
index f01c896d8..c438ff783 100644
--- a/tools/cli/bash.go
+++ b/tools/cli/bash.go
@@ -11,8 +11,8 @@ import (
 
 var _ = fmt.Print
 
-func bash_completion_script(commands []string) ([]byte, error) {
-	script := `_ksi_completions() {
+func bash_completion_script(commands []string) (string, error) {
+	return `_ksi_completions() {
     builtin local src
     builtin local limit
     # Send all words up to the word the cursor is currently on
@@ -27,8 +27,7 @@ builtin complete -F _ksi_completions kitty
 builtin complete -F _ksi_completions edit-in-kitty
 builtin complete -F _ksi_completions clone-in-kitty
 builtin complete -F _ksi_completions kitten
-`
-	return []byte(script), nil
+`, nil
 }
 
 func bash_output_serializer(completions []*Completions, shell_state map[string]string) ([]byte, error) {
diff --git a/tools/cli/completion-main.go b/tools/cli/completion-main.go
index 6840974ad..55821fd1f 100644
--- a/tools/cli/completion-main.go
+++ b/tools/cli/completion-main.go
@@ -30,7 +30,7 @@ func json_output_serializer(completions []*Completions, shell_state map[string]s
 	return json.Marshal(completions)
 }
 
-type completion_script_func func(commands []string) ([]byte, error)
+type completion_script_func func(commands []string) (string, error)
 type parser_func func(data []byte, shell_state map[string]string) ([][]string, error)
 type serializer_func func(completions []*Completions, shell_state map[string]string) ([]byte, error)
 
@@ -65,7 +65,7 @@ func GenerateCompletions(args []string) error {
 	}
 	if output_type == "setup" {
 		if len(args) == 0 {
-			return fmt.Errorf("The shell needs to be specified")
+			return fmt.Errorf("The shell must be specified")
 		}
 		shell_name := args[0]
 		args = args[1:]
@@ -75,7 +75,7 @@ func GenerateCompletions(args []string) error {
 		}
 		output, err := completion_script(args)
 		if err == nil {
-			_, err = os.Stdout.Write(output)
+			_, err = os.Stdout.WriteString(output)
 		}
 		return err
 	}
diff --git a/tools/cli/fish.go b/tools/cli/fish.go
index ea139de69..c9068fcb8 100644
--- a/tools/cli/fish.go
+++ b/tools/cli/fish.go
@@ -12,7 +12,7 @@ import (
 
 var _ = fmt.Print
 
-func fish_completion_script(commands []string) ([]byte, error) {
+func fish_completion_script(commands []string) (string, error) {
 	// One command in fish requires one completion script.
 	// Usage: kitten __complete__ setup fish [kitty|kitten|clone-in-kitty]
 	all_commands := map[string]bool{
@@ -21,9 +21,7 @@ func fish_completion_script(commands []string) ([]byte, error) {
 		"kitten":         true,
 	}
 	if len(commands) == 0 {
-		for cmd, _ := range all_commands {
-			commands = append(commands, cmd)
-		}
+		commands = append(commands, utils.Keys(all_commands)...)
 	}
 	script := strings.Builder{}
 	script.WriteString(`function __ksi_completions
@@ -40,10 +38,10 @@ end
 			// Reserved for `setup SHELL [KEY=VALUE ...]`, not used now.
 			continue
 		} else {
-			return nil, fmt.Errorf("No fish completion script for command: %s", cmd)
+			return "", fmt.Errorf("No fish completion script for command: %s", cmd)
 		}
 	}
-	return []byte(script.String()), nil
+	return script.String(), nil
 }
 
 func fish_output_serializer(completions []*Completions, shell_state map[string]string) ([]byte, error) {
diff --git a/tools/cli/zsh.go b/tools/cli/zsh.go
index bf12de3cb..f810062fe 100644
--- a/tools/cli/zsh.go
+++ b/tools/cli/zsh.go
@@ -15,8 +15,8 @@ import (
 
 var _ = fmt.Print
 
-func zsh_completion_script(commands []string) ([]byte, error) {
-	script := `#compdef kitty
+func zsh_completion_script(commands []string) (string, error) {
+	return `#compdef kitty
 
 _kitty() {
     (( ${+commands[kitten]} )) || builtin return
@@ -31,8 +31,7 @@ if (( $+functions[compdef] )); then
     compdef _kitty clone-in-kitty
     compdef _kitty kitten
 fi
-`
-	return []byte(script), nil
+`, nil
 }
 
 func shell_input_parser(data []byte, shell_state map[string]string) ([][]string, error) {