diff --git a/dev/flags/README b/dev/flags/README
new file mode 100644
index 0000000..7693c74
--- /dev/null
+++ b/dev/flags/README
@@ -0,0 +1,12 @@
+This needs to be built from the top makefile, for example :
+
+    make dev/flags/flags
+
+Then the executable is usable either one value at a time from the
+command line, either with values coming from stdin with "-" passed
+alone instead of the value.
+
+It is possible to restrict the decoding to certain fields only by
+specifying one of "ana", "chn", "conn", "cs", "si", "sierr", "strm",
+"task", or "txn" before the value.
+