diff --git a/warc-tiny b/warc-tiny
index f5ccf75..b26ac27 100755
--- a/warc-tiny
+++ b/warc-tiny
@@ -445,7 +445,7 @@ class ScrapeMode(ProcessMode):
 	def __init__(self, urlsOnly):
 		self._urlsOnly = urlsOnly
 
-		assert wpull is not None, 'Scrape mode requires wpull'
+		assert wpull is not None, 'Scrape mode requires wpull and lxml'
 		htmlParser = wpull.document.htmlparse.lxml_.HTMLParser()
 		elementWalker = wpull.scraper.html.ElementWalker()
 		scrapers = []