1 files changed, 4 insertions, 0 deletions
diff --git a/python/refcat/tasks.py b/python/refcat/tasks.py
index ec4d8a2..a5e5c72 100644
--- a/python/refcat/tasks.py
+++ b/python/refcat/tasks.py
@@ -299,6 +299,10 @@ class URLTabs(Refcat):
 class URLList(Refcat):
     """
     List of cleaned, unique URLs from refs.
+
+    For CDX lookup, we just want ^http, so:
+
+    $ zstdcat -T0 date-2021-05-06.tsv.zst | grep ^http > fatcat-refs-urllist-2021-05-06.tsv
     """
     def requires(self):
         return URLTabs()