diff --git a/api/tools.go b/api/tools.go
index d652077..322aa51 100644
--- a/api/tools.go
+++ b/api/tools.go
@@ -40,4 +40,3 @@ func ReceivePost[T any](c *fiber.Ctx) (*T, error) {
 
   return result, nil
 }
-
diff --git a/data/models.go b/data/models.go
index 6aafba5..b5e962f 100644
--- a/data/models.go
+++ b/data/models.go
@@ -1,21 +1,21 @@
 package data
 
 type Login struct {
-  Username string `db:"username" validate:"required"`
-  Password string `db:"password" validate:"required"`
+  Username string `db:"username" validate:"required,max=30"`
+  Password string `db:"password" validate:"required,max=128"`
 }
 
 type User struct {
-  Username string `db:"username" validate:"required"`
-  Email string `db:"email" validate:"required,email"`
-  Password string `db:"password" validate:"required"`
+  Username string `db:"username" validate:"required,max=30"`
+  Email string `db:"email" validate:"required,email,max=128"`
+  Password string `db:"password" validate:"required,min=8,max=64"`
 }
 
 type Link struct {
-  Id int `db:"id" json:"id"`
+  Id int `db:"id" json:"id" validate:"isdefault"`
   StreamId int `db:"stream_id" json:"stream_id" form:"stream_id" validate:"required,numeric"`
-  Url string `db:"url" json:"url" form:"url" validate:"required,http_url"`
-  Description string `db:"description" json:"description" form:"description" validate:"required"`
+  Url string `db:"url" json:"url" form:"url" validate:"required,http_url,max=150"`
+  Description string `db:"description" json:"description" form:"description" validate:"required,max=300"`
 }
 
 type Stream struct {