diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MergeResource.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MergeResource.java
index 5c484b3ce9..63fa2274ec 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MergeResource.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MergeResource.java
@@ -1,5 +1,7 @@
 package sonia.scm.api.v2.resources;
 
+import com.webcohesion.enunciate.metadata.rs.ResponseCode;
+import com.webcohesion.enunciate.metadata.rs.StatusCodes;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.http.HttpStatus;
 import sonia.scm.repository.NamespaceAndName;
@@ -35,6 +37,13 @@ public class MergeResource {
   @Path("")
   @Produces(VndMediaType.MERGE_RESULT)
   @Consumes(VndMediaType.MERGE_COMMAND)
+  @StatusCodes({
+    @ResponseCode(code = 204, condition = "merge has been executed successfully"),
+    @ResponseCode(code = 401, condition = "not authenticated / invalid credentials"),
+    @ResponseCode(code = 403, condition = "not authorized, the current user does not have the privilege to write the repository"),
+    @ResponseCode(code = 409, condition = "The branches could not be merged automatically due to conflicts (conflicting files will be returned)"),
+    @ResponseCode(code = 500, condition = "internal server error")
+  })
   public Response merge(@PathParam("namespace") String namespace, @PathParam("name") String name, @Valid MergeCommandDto mergeCommand) {
     NamespaceAndName namespaceAndName = new NamespaceAndName(namespace, name);
     log.info("Merge in Repository {}/{} from {} to {}", namespace, name, mergeCommand.getSourceRevision(), mergeCommand.getTargetRevision());
@@ -50,6 +59,12 @@ public class MergeResource {
 
   @POST
   @Path("dry-run/")
+  @StatusCodes({
+    @ResponseCode(code = 204, condition = "merge can be done automatically"),
+    @ResponseCode(code = 401, condition = "not authenticated / invalid credentials"),
+    @ResponseCode(code = 409, condition = "The branches can not be merged automatically due to conflicts"),
+    @ResponseCode(code = 500, condition = "internal server error")
+  })
   public Response dryRun(@PathParam("namespace") String namespace, @PathParam("name") String name, @Valid MergeCommandDto mergeCommand) {
     NamespaceAndName namespaceAndName = new NamespaceAndName(namespace, name);
     log.info("Merge in Repository {}/{} from {} to {}", namespace, name, mergeCommand.getSourceRevision(), mergeCommand.getTargetRevision());