diff --git a/core/controllers/HermesController.go b/core/controllers/HermesController.go
index 9368019..736b873 100644
--- a/core/controllers/HermesController.go
+++ b/core/controllers/HermesController.go
@@ -57,7 +57,7 @@ func (controller *HermesController) SendMail(context *gin.Context) {
 		mailTemplate.Subject = input.Subject
 	}
 
-	message, err := controller.handleMailMessage(mailTemplate, input.PlaceHolder)
+	message, err := controller.handleMailMessage(mailTemplate, input.Placeholder)
 
 	if err != nil {
 		context.JSON(common.ErrorHandlerHttpResponse(err))
diff --git a/core/http/requests/hermes-forms/SendMailFormRequest.go b/core/http/requests/hermes-forms/SendMailFormRequest.go
index 364d40f..5bde8f4 100644
--- a/core/http/requests/hermes-forms/SendMailFormRequest.go
+++ b/core/http/requests/hermes-forms/SendMailFormRequest.go
@@ -2,11 +2,22 @@ package hermes_forms
 
 type SendMailFormRequest struct {
 	// required: true
+	// type: string
 	Code string `json:"code" binding:"required"`
 	// required: true
-	Recipients  []string          `json:"recipients" binding:"required"`
-	PlaceHolder map[string]string `json:"placeholder" binding:"required"`
-	Subject     string            `json:"subject"`
+	// type: array
+	// items:
+	//   type: string
+	// example: ["email1@gmal.com", "email2@gmail.com"]
+	Recipients []string `json:"recipients" binding:"required"`
+	// required: false
+	// type: object
+	Placeholder map[string]string `json:"placeholder" binding:"required"`
+	// required: false
+	// type: string
+	// extensions:
+	//   x-note: All key must be capital the first character
+	Subject string `json:"subject"`
 }
 
 // swagger:parameters SendMail
diff --git a/docs/swagger.json b/docs/swagger.json
index 11a6001..155253c 100644
--- a/docs/swagger.json
+++ b/docs/swagger.json
@@ -73,13 +73,13 @@
                   "items": {
                     "$ref": "#/definitions/FeedbackModel"
                   }
-                },
-                "limit": {
-                  "type": "integer"
-                },
-                "offset": {
-                  "type": "integer"
                 }
+              },
+              "limit": {
+                "type": "integer"
+              },
+              "offset": {
+                "type": "integer"
               }
             }
           }
@@ -462,18 +462,23 @@
           "additionalProperties": {
             "type": "string"
           },
-          "x-go-name": "PlaceHolder"
+          "x-go-name": "Placeholder"
         },
         "recipients": {
           "type": "array",
           "items": {
             "type": "string"
           },
-          "x-go-name": "Recipients"
+          "x-go-name": "Recipients",
+          "example": [
+            "email1@gmal.com",
+            "email2@gmail.com"
+          ]
         },
         "subject": {
           "type": "string",
-          "x-go-name": "Subject"
+          "x-go-name": "Subject",
+          "x-note": "All key must be capital the first character"
         }
       },
       "x-go-package": "TSS-microservices/core/http/requests/hermes-forms"