diff --git a/server/open.go b/server/open.go
index 22ba233..25a436c 100644
--- a/server/open.go
+++ b/server/open.go
@@ -2,7 +2,7 @@ package server
 
 import (
 	"bytes"
-	"errors"
+	"fmt"
 	"io"
 	"os/exec"
 	"runtime"
@@ -22,9 +22,10 @@ func init() {
 
 // Open a url in the default browser
 func Open(url string) (io.Writer, error) {
-	open, err := cmd[runtime.GOOS]
+	goos := runtime.GOOS
+	open, err := cmd[goos]
 	if !err {
-		return nil, errors.New("This operating system is not supported.")
+		return nil, fmt.Errorf("operating system %q is not supported", goos)
 	}
 	cmd := exec.Command(open, url)
 	cmd.Stderr = &stderr
diff --git a/watcher/cmd.go b/watcher/cmd.go
index b168a0d..46214c7 100644
--- a/watcher/cmd.go
+++ b/watcher/cmd.go
@@ -81,7 +81,7 @@ func (h *Blueprint) Remove(p *cli.Context) error {
 			return nil
 		}
 	}
-	return errors.New("No project found.")
+	return errors.New("no project found")
 }
 
 // List of all the projects
@@ -144,5 +144,5 @@ func (h *Blueprint) check() error {
 		h.Clean()
 		return nil
 	}
-	return errors.New("There are no projects. The config file is empty.")
+	return errors.New("there are no projects")
 }