diff --git a/src/test/java/org/hyperagents/yggdrasil/BodyNotificationTest.java b/src/test/java/org/hyperagents/yggdrasil/BodyNotificationTest.java
index 16734f14..7b3a5f30 100644
--- a/src/test/java/org/hyperagents/yggdrasil/BodyNotificationTest.java
+++ b/src/test/java/org/hyperagents/yggdrasil/BodyNotificationTest.java
@@ -17,7 +17,6 @@
 import java.nio.file.Path;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import org.apache.hc.core5.http.HttpStatus;
@@ -302,60 +301,60 @@ public void testRun(final VertxTestContext ctx) throws URISyntaxException, IOExc
           );
           Assertions.assertNull(r.bodyAsString(), RESPONSE_BODY_EMPTY_MESSAGE);
         })
-        .compose(r -> this.callbackMessages
-                          .get(2)
-                          .future()
-                          .compose(r1 -> this.callbackMessages
-                                             .get(3)
-                                             .future()
-                          .onSuccess(r2 -> {
-                            Assertions.assertEquals(
-                                this.getUrl(
-                                  WORKSPACES_PATH
-                                  + MAIN_WORKSPACE_NAME
-                                  + BODIES_PATH
-                                  + TEST_AGENT_NAME
-                                ),
-                                r1.getKey(),
-                                URIS_EQUAL_MESSAGE
-                            );
-                            Assertions.assertEquals(
-                                this.getUrl(
-                                  WORKSPACES_PATH
-                                  + MAIN_WORKSPACE_NAME
-                                  + BODIES_PATH
-                                  + TEST_AGENT_NAME
-                                ),
-                                r2.getKey(),
-                                URIS_EQUAL_MESSAGE
-                            );
-                            Assertions.assertEquals(
-                                Set.of(
-                                  JsonObject
-                                    .of(
-                                      "artifactName",
-                                      COUNTER_ARTIFACT_NAME,
-                                      "actionName",
-                                      "inc",
-                                      "eventType",
-                                      "actionRequested"
-                                    )
-                                    .encode(),
-                                  JsonObject
-                                    .of(
-                                      "artifactName",
-                                      COUNTER_ARTIFACT_NAME,
-                                      "actionName",
-                                      "inc",
-                                      "eventType",
-                                      "actionSucceeded"
-                                    )
-                                    .encode()
-                                ),
-                                Set.of(r1.getValue(), r2.getValue()),
-                                REPRESENTATIONS_EQUAL_MESSAGE
-                            );
-                          })))
+        .compose(r -> this.callbackMessages.get(2).future())
+        .onSuccess(m -> {
+          Assertions.assertEquals(
+              this.getUrl(
+                WORKSPACES_PATH
+                + MAIN_WORKSPACE_NAME
+                + BODIES_PATH
+                + TEST_AGENT_NAME
+              ),
+              m.getKey(),
+              URIS_EQUAL_MESSAGE
+          );
+          Assertions.assertEquals(
+              JsonObject
+                .of(
+                  "artifactName",
+                  COUNTER_ARTIFACT_NAME,
+                  "actionName",
+                  "inc",
+                  "eventType",
+                  "actionRequested"
+                )
+                .encode(),
+              m.getValue(),
+              REPRESENTATIONS_EQUAL_MESSAGE
+          );
+        })
+        .compose(r -> this.callbackMessages.get(3).future())
+        .onSuccess(m -> {
+          Assertions.assertEquals(
+              this.getUrl(
+                WORKSPACES_PATH
+                + MAIN_WORKSPACE_NAME
+                + BODIES_PATH
+                + TEST_AGENT_NAME
+              ),
+              m.getKey(),
+              URIS_EQUAL_MESSAGE
+          );
+          Assertions.assertEquals(
+              JsonObject
+                .of(
+                  "artifactName",
+                  COUNTER_ARTIFACT_NAME,
+                  "actionName",
+                  "inc",
+                  "eventType",
+                  "actionSucceeded"
+                )
+                .encode(),
+              m.getValue(),
+              REPRESENTATIONS_EQUAL_MESSAGE
+          );
+        })
         .onComplete(ctx.succeedingThenComplete());
   }
 
diff --git a/yggdrasil-cartago/src/main/java/org/hyperagents/yggdrasil/cartago/CartagoVerticle.java b/yggdrasil-cartago/src/main/java/org/hyperagents/yggdrasil/cartago/CartagoVerticle.java
index 75f5a36e..5a6a030b 100644
--- a/yggdrasil-cartago/src/main/java/org/hyperagents/yggdrasil/cartago/CartagoVerticle.java
+++ b/yggdrasil-cartago/src/main/java/org/hyperagents/yggdrasil/cartago/CartagoVerticle.java
@@ -294,6 +294,12 @@ private Future<Optional<String>> doAction(
     final var promise = Promise.<Void>promise();
     final var workspace = this.workspaceRegistry.getWorkspace(workspaceName).orElseThrow();
     final var agentName = this.getAgentNameFromAgentUri(agentUri);
+    this.dispatcherMessagebox.sendMessage(
+      new HttpNotificationDispatcherMessage.ActionRequested(
+        this.httpConfig.getAgentBodyUri(workspaceName, agentName),
+        this.getActionNotificationContent(artifactName, action).encode()
+      )
+    );
     workspace.execOp(0L,
                      this.getAgentId(this.getAgentCredential(agentUri), workspace.getId()),
                      e -> {
@@ -301,7 +307,7 @@ private Future<Optional<String>> doAction(
                          this.dispatcherMessagebox.sendMessage(
                            new HttpNotificationDispatcherMessage.ActionSucceeded(
                              this.httpConfig.getAgentBodyUri(workspaceName, agentName),
-                             this.getActionNotificationContent(artifactName, action)
+                             this.getActionNotificationContent(artifactName, action).encode()
                            )
                          );
                          promise.complete();
@@ -310,6 +316,8 @@ private Future<Optional<String>> doAction(
                            new HttpNotificationDispatcherMessage.ActionFailed(
                              this.httpConfig.getAgentBodyUri(workspaceName, agentName),
                              this.getActionNotificationContent(artifactName, action)
+                                 .put("cause", f.getFailureMsg())
+                                 .encode()
                            )
                          );
                          promise.fail(f.getFailureMsg());
@@ -319,12 +327,6 @@ private Future<Optional<String>> doAction(
                      operation,
                      -1,
                      null);
-    this.dispatcherMessagebox.sendMessage(
-      new HttpNotificationDispatcherMessage.ActionRequested(
-        this.httpConfig.getAgentBodyUri(workspaceName, agentName),
-        this.getActionNotificationContent(artifactName, action)
-      )
-    );
     return promise.future()
                   .map(ignored ->
                     Optional.ofNullable(feedbackParameter.get())
@@ -338,15 +340,13 @@ private Future<Optional<String>> doAction(
                   );
   }
 
-  private String getActionNotificationContent(final String artifactName, final String action) {
-    return JsonObject
-      .of(
-        "artifactName",
-        artifactName,
-        "actionName",
-        action
-      )
-      .encode();
+  private JsonObject getActionNotificationContent(final String artifactName, final String action) {
+    return JsonObject.of(
+      "artifactName",
+      artifactName,
+      "actionName",
+      action
+    );
   }
 
   private String getAgentNameFromAgentUri(final String agentUri) {