diff --git a/parambulator.js b/parambulator.js
index 864187c..d727510 100644
--- a/parambulator.js
+++ b/parambulator.js
@@ -583,15 +583,15 @@
     }
 
     var err = new Error( msg )
-    err.parambulator = {
-      code:code,
-      property:ctxt.prop,
-      value:ctxt.point,
-      expected:ctxt.rule.spec,
 
-      parents:ctxt.parents,
-      point:ctxt.point,
-      rule:ctxt.rule}
+    err.parambulator = {
+      code:     code,
+      property: ctxt.prop,
+      value:    ctxt.point,
+      expected: (ctxt.rule ? ctxt.rule.spec : void 0),
+      parents:  ctxt.parents,
+      point:    ctxt.point,
+      rule:     ctxt.rule}
 
     return cb(err)
   }
diff --git a/test/parambulator.spec.js b/test/parambulator.spec.js
index 92d5744..5334ff7 100644
--- a/test/parambulator.spec.js
+++ b/test/parambulator.spec.js
@@ -59,6 +59,13 @@ describe('parambulator', function() {
   })
 
 
+  it('no_input', function() {
+    pb.validate(void 0,function(err){
+      assert.equal('no_input$',err.parambulator.code)
+    })
+  })
+
+
   it('required$', function() {
     pb.validate({a:1,z:1,red:1,foo:1,bar:1},function(err,res){
       assert.isNull(err)