diff --git a/facebox/facebox.go b/facebox/facebox.go
index d8e5df9..3d83ac6 100644
--- a/facebox/facebox.go
+++ b/facebox/facebox.go
@@ -83,7 +83,7 @@ func (c *Client) Info() (*boxutil.Info, error) {
 	return &info, nil
 }
 
-// ErrFacebox represents an error from facebox.
+// ErrFacebox represents an error from Facebox.
 type ErrFacebox string
 
 func (e ErrFacebox) Error() string {
diff --git a/fakebox/fakebox.go b/fakebox/fakebox.go
index 2096c66..722feb8 100644
--- a/fakebox/fakebox.go
+++ b/fakebox/fakebox.go
@@ -157,7 +157,7 @@ func (c *Client) Check(title string, content string, u *url.URL) (*Analysis, err
 		return nil, errors.Wrap(err, "decoding response")
 	}
 	if !response.Success {
-		return nil, ErrNewsbox(response.Error)
+		return nil, ErrFakebox(response.Error)
 	}
 	return &Analysis{
 		Title:   response.Title,
@@ -166,9 +166,9 @@ func (c *Client) Check(title string, content string, u *url.URL) (*Analysis, err
 	}, nil
 }
 
-// ErrNewsbox represents an error from fakebox.
-type ErrNewsbox string
+// ErrFakebox represents an error from Fakebox.
+type ErrFakebox string
 
-func (e ErrNewsbox) Error() string {
+func (e ErrFakebox) Error() string {
 	return "fakebox: " + string(e)
 }
diff --git a/nudebox/nudebox.go b/nudebox/nudebox.go
index f688f4e..b42ed15 100644
--- a/nudebox/nudebox.go
+++ b/nudebox/nudebox.go
@@ -179,7 +179,7 @@ func (c *Client) parseCheckResponse(r io.Reader) (float64, error) {
 	return checkResponse.Nude, nil
 }
 
-// ErrNudebox represents an error from nudebox.
+// ErrNudebox represents an error from Nudebox.
 type ErrNudebox string
 
 func (e ErrNudebox) Error() string {
diff --git a/tagbox/tagbox.go b/tagbox/tagbox.go
index 7c4bfa3..71826e1 100644
--- a/tagbox/tagbox.go
+++ b/tagbox/tagbox.go
@@ -77,7 +77,7 @@ type CheckResponse struct {
 	CustomTags []Tag `json:"custom_tags"`
 }
 
-// ErrTagbox represents an error from tagbox.
+// ErrTagbox represents an error from Tagbox.
 type ErrTagbox string
 
 func (e ErrTagbox) Error() string {
diff --git a/textbox/textbox.go b/textbox/textbox.go
index dc15396..bebad28 100644
--- a/textbox/textbox.go
+++ b/textbox/textbox.go
@@ -147,7 +147,7 @@ func (c *Client) Check(r io.Reader) (*Analysis, error) {
 	}, nil
 }
 
-// ErrTextbox represents an error from textbox.
+// ErrTextbox represents an error from Textbox.
 type ErrTextbox string
 
 func (e ErrTextbox) Error() string {
diff --git a/videobox/videobox.go b/videobox/videobox.go
index bd2a351..8fddc81 100644
--- a/videobox/videobox.go
+++ b/videobox/videobox.go
@@ -74,7 +74,7 @@ func (c *Client) Info() (*boxutil.Info, error) {
 	return &info, nil
 }
 
-// ErrVideobox represents an error from facebox.
+// ErrVideobox represents an error from Videobox.
 type ErrVideobox string
 
 func (e ErrVideobox) Error() string {
diff --git a/x/boxutil/doc.go b/x/boxutil/doc.go
index 481754f..ed1eaa7 100644
--- a/x/boxutil/doc.go
+++ b/x/boxutil/doc.go
@@ -1,2 +1,2 @@
-// Package boxutil is DEPCREATED. Use github.com/machinebox/sdk-go/boxutil instead.
+// Package boxutil is DEPCREATED and you should use github.com/machinebox/sdk-go/boxutil instead.
 package boxutil