diff --git a/delivery/http_server/end2end/agent_kindbox_test.go b/delivery/http_server/end2end/agent_kindbox_test.go
index 6a9d12d..a9dd9df 100644
--- a/delivery/http_server/end2end/agent_kindbox_test.go
+++ b/delivery/http_server/end2end/agent_kindbox_test.go
@@ -4,9 +4,11 @@
 package end2end
 
 import (
+	"bytes"
 	"context"
 	"encoding/json"
 	"fmt"
+	"log"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -14,21 +16,23 @@ import (
 	"git.gocasts.ir/ebhomengo/niki/delivery/http_server/end2end/setup"
 	"git.gocasts.ir/ebhomengo/niki/entity"
 	adminserviceparam "git.gocasts.ir/ebhomengo/niki/param/admin/admin"
-	param "git.gocasts.ir/ebhomengo/niki/param/agent/kind_box"
+	adminParam "git.gocasts.ir/ebhomengo/niki/param/admin/kind_box"
+	agentParam "git.gocasts.ir/ebhomengo/niki/param/agent/kind_box"
 	"github.com/labstack/echo/v4"
 	"github.com/stretchr/testify/assert"
 )
 
 const (
-	agentPhoneNumber = "09384664403"
-	agentPassword    = "Abc123456"
+	agentPhoneNumber      = "09384664403"
+	agentPassword         = "Abc123456"
+	agentID          uint = 4
 )
 
 func TestAgent_KindBox_Get(t *testing.T) {
 	kindBox := entity.KindBox{
 		ID:              2,
 		SerialNumber:    "serial-2",
-		ReceiverAgentID: 4,
+		ReceiverAgentID: agentID,
 		Status:          entity.KindBoxAssignedReceiverAgentStatus,
 	}
 	url := fmt.Sprintf("/agents/kindboxes/%d", kindBox.ID)
@@ -41,8 +45,8 @@ func TestAgent_KindBox_Get(t *testing.T) {
 		t.Fatalf("could not login: %s", err)
 	}
 
-	resRecord := createRequest(http.MethodGet, url, token)
-	var res param.GetKindBoxResponse
+	resRecord := createRequest(http.MethodGet, url, token, nil)
+	var res agentParam.GetKindBoxResponse
 	err = json.NewDecoder(resRecord.Body).Decode(&res)
 	assert.NoError(t, err, "could not decode response body")
 
@@ -53,6 +57,35 @@ func TestAgent_KindBox_Get(t *testing.T) {
 	assert.Equal(t, kindBox.Status, res.Status)
 }
 
+// TODO: we can add more tests for return.
+// we can get check if the data is updated in db as expects
+// or api should return error if the kindbox is not for this agent
+// CHECK: is the flow correct? agent can change kindbox status to return no matter what was the previous status?
+func TestAgent_KindBox_Return(t *testing.T) {
+	kindBoxReqBody := agentParam.ReturnKindBoxRequest{SerialNumber: "new-serial"}
+	var kindBoxID uint = 2
+	url := fmt.Sprintf("/agents/kindboxes/return/%d", kindBoxID)
+
+	teardown := setup.SeedMariaDB(testContainer.GetMariaDBConfig())
+	t.Cleanup(teardown)
+
+	token, err := getToken()
+	if err != nil {
+		t.Fatalf("could not login: %s", err)
+	}
+
+	resRecord := createRequest(http.MethodPatch, url, token, kindBoxReqBody)
+	updatedKindBox, err := services.AdminKindBoxSvc.Get(
+		context.Background(),
+		adminParam.KindBoxGetRequest{KindBoxID: kindBoxID},
+	)
+
+	assert.Equal(t, http.StatusNoContent, resRecord.Code)
+	assert.Equal(t, kindBoxReqBody.SerialNumber, updatedKindBox.SerialNumber)
+	assert.Equal(t, agentID, updatedKindBox.ReceiverAgentID)
+	assert.Equal(t, entity.KindBoxReturnedStatus, updatedKindBox.Status)
+}
+
 func getToken() (string, error) {
 	res, err := services.AdminSvc.LoginWithPhoneNumber(
 		context.Background(),
@@ -67,8 +100,21 @@ func getToken() (string, error) {
 	return res.Tokens.AccessToken, nil
 }
 
-func createRequest(method string, url string, token string) *httptest.ResponseRecorder {
-	req := httptest.NewRequest(method, url, nil)
+func createRequest(
+	method string,
+	url string,
+	token string,
+	body any,
+) *httptest.ResponseRecorder {
+	var buf bytes.Buffer
+	if body != nil {
+		err := json.NewEncoder(&buf).Encode(body)
+		if err != nil {
+			log.Fatalf("could not encode body: %v", err)
+		}
+	}
+
+	req := httptest.NewRequest(method, url, &buf)
 	req.Header.Set(echo.HeaderContentType, echo.MIMEApplicationJSON)
 	req.Header.Set(echo.HeaderAuthorization, fmt.Sprintf("Bearer %s", token))
 	res := httptest.NewRecorder()