diff --git a/services/external-actor-gateway-service/openapi.yaml b/services/external-actor-gateway-service/openapi.yaml
index d657660..da37028 100644
--- a/services/external-actor-gateway-service/openapi.yaml
+++ b/services/external-actor-gateway-service/openapi.yaml
@@ -2018,6 +2018,34 @@ components:
                             - type
                             - toolCallId
                           additionalProperties: false
+                        - type: object
+                          properties:
+                            type:
+                              type: string
+                              const: artifact
+                            artifactId:
+                              type: string
+                            path:
+                              type: string
+                            title:
+                              type: string
+                            kind:
+                              type: string
+                              enum:
+                                - email
+                                - call-script
+                                - document
+                            previewText:
+                              anyOf:
+                                - type: string
+                                - type: "null"
+                          required:
+                            - type
+                            - artifactId
+                            - path
+                            - title
+                            - kind
+                          additionalProperties: false
                         - type: object
                           properties:
                             type: