diff --git a/sync-http-to-s3.groovy b/sync-http-to-s3.groovy
index 976272c..e9b83af 100644
--- a/sync-http-to-s3.groovy
+++ b/sync-http-to-s3.groovy
@@ -1,6 +1,19 @@
+/**
+ * File upload to AWS S3 pipeline
+ *
+ * Expected parameters:
+ *   DEST         S3 bucket to upload files to (e.g. s3://images-mirantis-com)
+ *   IMAGE        The image with s4cmd utility installed
+ *   SOURCE       The source URL to download files from (e.g. http://images.mcp.mirantis.net)
+ *   FILENAMES    Relative path to files. (SOURCE and FILENAMES values are being
+ *                concantenated to form URL to download files from.)
+ *   FORCE_UPLOAD Force file upload (will overwrite existing destination file)
+ */
+
 def common = new com.mirantis.mk.Common()
 def s4cmdOpts = ' --sync-check '
 Boolean forceUpload = (env.FORCE_UPLOAD ?: false).toBoolean()
+def wgetTries = env.WGET_TRIES ?: '50'
 
 node("docker") {
     stage('Prepare') {
@@ -21,7 +34,7 @@
                                   usernameVariable: 'S3_ACCESS_KEY', passwordVariable: 'S3_SECRET_KEY']]) {
                     img.inside("-e S3_ACCESS_KEY=${S3_ACCESS_KEY} -e S3_SECRET_KEY=${S3_SECRET_KEY}") {
                         common.retry(3, 5) {
-                            sh(script: "wget --progress=dot:giga --tries=50 -O ${filename} ${url}", returnStdout: true)
+                            sh(script: "wget --progress=dot:giga --tries=${wgetTries} -O ${filename} ${url}", returnStdout: true)
                             sh(script: "/usr/local/bin/s4cmd put ${opts} ${filename} ${DEST}/${filenamePath}", returnStdout: true)
                         }
                     }