diff --git a/dudeswave/src/dudeswave_user_handler.erl b/dudeswave/src/dudeswave_user_handler.erl
index 9bd14e4..50f2183 100644
--- a/dudeswave/src/dudeswave_user_handler.erl
+++ b/dudeswave/src/dudeswave_user_handler.erl
@@ -21,14 +21,22 @@ The username is passed in a cookie. The handler recover it from the
 session. Cookies are:
 
 ```
-dudename # the actual username
-dudeauth # the authentication cookie
+dudename: the actual username
+dudeauth: the authentication cookie
 ```
 
 If the session is not valid, all the requests will return `403 Forbidden` to
 the client. In case a technical problem occurs, `500 Internal Server Error`
 is returned.
 
+In case of errors, all the methods returns a JSON response in the form:
+
+```
+{
+	"error": "error string"
+}
+```
+
 This module accepts four methods:
 
 - GET /api/v1/user
@@ -56,6 +64,8 @@ JSON APIs
 
 GET /api/v1/user
 
+Response body:
+
 ```
 {
 	"user" : "foo",
@@ -79,6 +89,14 @@ PUT /api/v1/user
 }
 ```
 
+Response body:
+
+```
+{
+	"result": "created"
+}
+```
+
 Response codes:
 
 - 201 Created
@@ -95,6 +113,14 @@ POST /api/v1/user
 }
 ```
 
+Response body:
+
+```
+{
+	"result": "updated"
+}
+```
+
 Response codes:
 
 - 200 OK
@@ -103,6 +129,16 @@ Response codes:
 
 DELETE /api/v1/user
 
+Response body:
+
+```
+{
+	"result": "deleted"
+}
+```
+
+Response codes:
+
 - 202 Accepted
 - 404 Not Found
 
@@ -147,7 +183,10 @@ forbidden(Req, State) ->
 
 			case dudeswave_auth:authenticate({cookie, User, Auth}, Bucket) of
 				{error, service_unavailable} -> exit(service_unavailable);
-				true -> {false, Req, State};
+				true ->
+					Resp = json:encode(#{<<"error">> => <<"authentication required">>}),
+					Req0 = cowboy_req:reply(403, #{}, Resp, Req),
+					{false, Req0, State};
 				false -> {true, Req, State}
 			end
 	end.
@@ -177,8 +216,14 @@ resource_exists(Req, State) ->
 	{ok, Bucket} = maps:find(bucket, State),
 
 	case dudeswave_auth:user_details(User, Bucket) of
-		[] -> {false, Req, State};
-		{error, Reason} -> exit(Reason);
+		[] ->
+			Resp = json:encode(#{<<"error">> => <<"user does not exists">>}),
+			Req0 = cowboy_req:reply(404, #{}, Resp, Req),
+			{false, Req0, State};
+		{error, _} ->
+			Resp = json:encode(#{<<"error">> => <<"internal server error">>}),
+			Req0 = cowboy_req:reply(500, #{}, Resp, Req),
+			{false, Req0, State};
 		Details ->
 			NewState = State#{
 			    bucket => Bucket,
@@ -203,11 +248,17 @@ delete_resource(Req, State) ->
 	#{dudename := User} = cowboy_req:match_cookies([dudename], Req),
 
 	case dudeswave_auth:delete(User, Bucket) of
-		ok -> {true, Req, State};
-		{error, _} -> {false, Req, State}
+		ok ->
+			Resp = json:encode(#{<<"result">> => <<"deleted">>}),
+			Req0 = cowboy_req:reply(200, #{}, Resp, Req),
+			{true, Req0, State};
+		{error, _} ->
+			Resp = json:encode(#{<<"error">> => <<"internal server error">>}),
+			Req0 = cowboy_req:reply(500, #{}, Resp, Req),
+			{false, Req0, State}
 	end.
 
-delete_completed(Req, State) -> {false, Req, State}.
+delete_completed(Req, State) -> {true, Req, State}.
 
 %
 % Custom callbacks
@@ -220,8 +271,14 @@ create_user(Req, State) ->
 	#{<<"password">> := Pass, <<"email">> := Email}  = json:decode(cowboy_req:body(req)),
 
 	case dudeswave_auth:new_user(User, Pass, Email, Bucket) of
-		ok -> {true, Req, []};
-		{error, Reason} -> {false, Req, Reason}
+		ok ->
+			Resp = json:encode(#{<<"result">> => <<"created">>}),
+			Req0 = cowboy_req:reply(201, #{}, Resp, Req),
+			{true, Req0, []};
+		{error, Reason} ->
+			Resp = json:encode(#{<<"error">> => <<"internal server error">>}),
+			Req0 = cowboy_req:reply(500, #{}, Resp, Req),
+			{false, Req0, Reason}
 	end.
 
 modify_user(Req, State) ->
@@ -232,8 +289,14 @@ modify_user(Req, State) ->
 	    <<"name">> := Name} = json:decode(cowboy_req:body(req)),
 
 	case dudeswave_auth:update(User, Name, Email, Desc, Bucket) of
-		ok -> {true, Req, []};
-		{error, Reason} -> {false, Req, Reason}
+		ok ->
+			Resp = json:encode(#{<<"result">> => <<"details updated">>}),
+			Req0 = cowboy_req:reply(200, #{}, Resp, Req),
+			{true, Req0, []};
+		{error, Reason} ->
+			Resp = json:encode(#{<<"error">> => <<"internal server error">>}),
+			Req0 = cowboy_req:reply(500, #{}, Resp, Req),
+			{false, Req0, Reason}
 	end.
 
 user_details(Req, State) ->