diff --git a/xml/api/digests-2.9.rng b/xml/api/digests-2.9.rng
new file mode 100644
index 0000000000..3d00628bdb
--- /dev/null
+++ b/xml/api/digests-2.9.rng
@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<grammar xmlns="http://relaxng.org/ns/structure/1.0"
+         datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
+
+    <start>
+        <ref name="element-digests"/>
+    </start>
+
+    <define name="element-digests">
+        <element name="digests">
+            <attribute name="resource"> <text/> </attribute>
+            <attribute name="node"> <text/> </attribute>
+            <attribute name="task"> <text/> </attribute>
+            <attribute name="interval"> <text/> </attribute>
+            <zeroOrMore>
+                <ref name="element-digest"/>
+            </zeroOrMore>
+        </element>
+    </define>
+
+    <define name="element-digest">
+        <element name="digest">
+            <attribute name="type"> <text/> </attribute>
+            <attribute name="hash"> <text/> </attribute>
+            <optional>
+                <element name="parameters">
+                    <zeroOrMore>
+                        <attribute>
+                          <anyName/>
+                          <text/>
+                        </attribute>
+                    </zeroOrMore>
+                </element>
+            </optional>
+        </element>
+    </define>
+</grammar>