diff --git a/README.md b/README.md
index 6ceeb19de696..0f7dbe5a6b40 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,26 @@
 tests
 =====
+
+Common tests for all clients to test against.
+
+All files should be of the form:
+
+```
+{
+	"test1name":
+	{
+		"test1property1": ...,
+		"test1property2": ...,
+		...
+	},
+	"test2name":
+	{
+		"test2property1": ...,
+		"test2property2": ...,
+		...
+	}
+}
+```
+
+Arrays are allowed, but don't use them for sets of properties - only use them for data that is clearly a continuous contiguous sequence of values.
+