diff --git a/build.gradle.kts b/build.gradle.kts
index 36f4c7e..2f95015 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -332,6 +332,12 @@ tasks.register("testCitizens", Test::class) {
         includeTags("citizen")
     }
 }
+tasks.register("testComments", Test::class) {
+    group = "tests"
+    useJUnitPlatform {
+        includeTags("comment")
+    }
+}
 
 dependencyCheck {
     formats = listOf(ReportGenerator.Format.HTML, ReportGenerator.Format.XML)
diff --git a/src/main/kotlin/fr/dcproject/component/comment/article/routes/CreateCommentArticle.kt b/src/main/kotlin/fr/dcproject/component/comment/article/routes/CreateCommentArticle.kt
index fd10799..493f9aa 100644
--- a/src/main/kotlin/fr/dcproject/component/comment/article/routes/CreateCommentArticle.kt
+++ b/src/main/kotlin/fr/dcproject/component/comment/article/routes/CreateCommentArticle.kt
@@ -1,6 +1,6 @@
 package fr.dcproject.component.comment.article.routes
 
-import fr.dcproject.common.response.toOutput
+import fr.dcproject.application.http.badRequestIfNotValid
 import fr.dcproject.common.security.assert
 import fr.dcproject.common.utils.receiveOrBadRequest
 import fr.dcproject.component.article.database.ArticleRef
@@ -12,6 +12,9 @@ import fr.dcproject.component.comment.article.routes.CreateCommentArticle.PostAr
 import fr.dcproject.component.comment.generic.CommentAccessControl
 import fr.dcproject.component.comment.generic.database.CommentForUpdate
 import fr.dcproject.component.comment.toOutput
+import io.konform.validation.Validation
+import io.konform.validation.jsonschema.maxLength
+import io.konform.validation.jsonschema.minLength
 import io.ktor.application.call
 import io.ktor.http.HttpStatusCode
 import io.ktor.locations.KtorExperimentalLocationsAPI
@@ -26,27 +29,36 @@ object CreateCommentArticle {
     @Location("/articles/{article}/comments")
     class PostArticleCommentRequest(article: UUID) {
         val article = ArticleRef(article)
-        class Input(val content: String)
+        class Input(val content: String) {
+            fun validate() = Validation<Input> {
+                Input::content {
+                    minLength(20)
+                    maxLength(6000)
+                }
+            }.validate(this)
+        }
     }
 
     fun Route.createCommentArticle(repo: CommentArticleRepository, ac: CommentAccessControl) {
         post<PostArticleCommentRequest> {
             mustBeAuth()
-            call.receiveOrBadRequest<Input>().run {
-                CommentForUpdate(
-                    target = it.article,
-                    createdBy = citizen,
-                    content = content
-                )
-            }.let { comment ->
-                ac.assert { canCreate(comment, citizenOrNull) }
-                repo.comment(comment)
+            call.receiveOrBadRequest<Input>()
+                .apply { validate().badRequestIfNotValid() }
+                .run {
+                    CommentForUpdate(
+                        target = it.article,
+                        createdBy = citizen,
+                        content = content
+                    )
+                }.let { comment ->
+                    ac.assert { canCreate(comment, citizenOrNull) }
+                    repo.comment(comment)
 
-                call.respond(
-                    HttpStatusCode.Created,
-                    comment.toOutput()
-                )
-            }
+                    call.respond(
+                        HttpStatusCode.Created,
+                        comment.toOutput()
+                    )
+                }
         }
     }
 }
diff --git a/src/main/resources/openapi.yaml b/src/main/resources/openapi.yaml
index af39955..810cb48 100644
--- a/src/main/resources/openapi.yaml
+++ b/src/main/resources/openapi.yaml
@@ -563,6 +563,12 @@ paths:
             application/json:
               schema:
                 $ref: '#/components/schemas/CommentResponse'
+        400:
+          description: BadReqest
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/400'
         401:
           $ref: '#/components/responses/401'
   /comments/{comment}:
diff --git a/src/test/kotlin/integration/Comment articles routes.kt b/src/test/kotlin/integration/Comment articles routes.kt
index 6c7c00e..0962e86 100644
--- a/src/test/kotlin/integration/Comment articles routes.kt	
+++ b/src/test/kotlin/integration/Comment articles routes.kt	
@@ -1,6 +1,8 @@
 package integration
 
 import fr.dcproject.component.citizen.database.CitizenI.Name
+import integration.steps.`when`.Validate.ALL
+import integration.steps.`when`.Validate.REQUEST_BODY
 import integration.steps.`when`.`When I send a GET request`
 import integration.steps.`when`.`When I send a POST request`
 import integration.steps.`when`.`When I send a PUT request`
@@ -13,6 +15,7 @@ import integration.steps.then.`And the response should contain`
 import integration.steps.then.`And the response should not be null`
 import integration.steps.then.`Then the response should be`
 import integration.steps.then.and
+import io.ktor.http.HttpStatusCode.Companion.BadRequest
 import io.ktor.http.HttpStatusCode.Companion.Created
 import io.ktor.http.HttpStatusCode.Companion.OK
 import org.junit.jupiter.api.Tag
@@ -33,14 +36,37 @@ class `Comment articles routes` : BaseTest() {
                 `with body`(
                     """
                     {
-                      "content": "Hello mister"
+                      "content": "Hello mister MARABOUTCHA"
                     }
                     """
                 )
             } `Then the response should be` Created and {
                 `And the response should not be null`()
                 `And the response should contain`("$.target.id", "aa16c635-28da-46f0-9a89-934eef88c7ca")
-                `And the response should contain`("$.content", "Hello mister")
+                `And the response should contain`("$.content", "Hello mister MARABOUTCHA")
+            }
+        }
+    }
+
+    @Test
+    @Tag("BadRequest")
+    fun `I cannot comment article with bad request`() {
+        withIntegrationApplication {
+            `Given I have citizen`("Michael", "Faraday")
+            `Given I have article`(id = "aa16c635-28da-46f0-9a89-934eef88c7ca")
+            `When I send a POST request`("/articles/aa16c635-28da-46f0-9a89-934eef88c7ca/comments", ALL - REQUEST_BODY) {
+                `authenticated as`("Michael", "Faraday")
+                `with body`(
+                    """
+                    {
+                      "content": "To small content"
+                    }
+                    """
+                )
+            } `Then the response should be` BadRequest and {
+                `And the response should not be null`()
+                `And the response should contain`("$.invalidParams[0].name", ".content")
+                `And the response should contain`("$.invalidParams[0].reason", "must have at least 20 characters")
             }
         }
     }