diff --git a/src/mako/cli/lib/engine.mako b/src/mako/cli/lib/engine.mako
index d118a6f266..661d3c63db 100644
--- a/src/mako/cli/lib/engine.mako
+++ b/src/mako/cli/lib/engine.mako
@@ -392,11 +392,12 @@ for kvarg in ${opt_values(KEY_VALUE_ARG)} {
     % for schema, fe, f in schema_fields:
 <%
     pname = FIELD_SEP.join(mangle_subcommand(t[1]) for t in f)
+    sname = FIELD_SEP.join(t[1] for t in f)
     ptype = actual_json_type(f[-1][1], fe.actual_property.type)
     jtype = 'JsonType::' + JSON_TYPE_TO_ENUM_MAP[ptype]
     ctype = 'ComplexType::' + CTYPE_TO_ENUM_MAP[fe.container_type]
 %>\
-            "${pname}" => Some(JsonTypeInfo { jtype: ${jtype}, ctype: ${ctype} }),
+            "${pname}" => Some(("${sname}", JsonTypeInfo { jtype: ${jtype}, ctype: ${ctype} })),
             % endfor # each nested field
             _ => {
                 let suggestion = FieldCursor::did_you_mean(key, &${field_vec(sorted(fields))});
@@ -404,8 +405,8 @@ for kvarg in ${opt_values(KEY_VALUE_ARG)} {
                 None
             }
         };
-    if let Some(type_info) = type_info {
-        temp_cursor.set_json_value(&mut object, value.unwrap(), type_info, err);
+    if let Some((field_cursor_str, type_info)) = type_info {
+        FieldCursor::from(field_cursor_str).set_json_value(&mut object, value.unwrap(), type_info, err, &temp_cursor);
     }
 }
 let mut ${request_prop_name}: api::${request_prop_type} = json::value::from_value(object).unwrap();
diff --git a/src/rust/cli/cmn.rs b/src/rust/cli/cmn.rs
index 79aad3f223..d4d131f762 100644
--- a/src/rust/cli/cmn.rs
+++ b/src/rust/cli/cmn.rs
@@ -122,6 +122,14 @@ impl ToString for  FieldCursor {
     }
 }
 
+impl From<&'static str> for FieldCursor {
+    fn from(value: &'static str) -> FieldCursor {
+        let mut res = FieldCursor::default();
+        res.set(value).unwrap();
+        res
+    }
+}
+
 impl FieldCursor {
     pub fn set(&mut self, value: &str) -> Result<(), CLIError> {
         if value.len() == 0 {
@@ -229,7 +237,8 @@ impl FieldCursor {
 
     pub fn set_json_value(&self, mut object: &mut Value, 
                                  value: &str, type_info: JsonTypeInfo,
-                                 err: &mut InvalidOptionsError) {
+                                 err: &mut InvalidOptionsError, 
+                                 orig_cursor: &FieldCursor) {
         assert!(self.0.len() > 0);
 
         for field in &self.0[..self.0.len()-1] {
@@ -267,7 +276,9 @@ impl FieldCursor {
 
                 match type_info.ctype {
                     ComplexType::Pod => {
-                        mapping.entry(field.to_owned()).or_insert(to_jval(value, type_info.jtype, err));
+                        if mapping.insert(field.to_owned(), to_jval(value, type_info.jtype, err)).is_some() {
+                            err.issues.push(CLIError::Field(FieldError::Duplicate(orig_cursor.to_string())));
+                        }
                     },
                     ComplexType::Vec => {
                         match *mapping.entry(field.to_owned())
@@ -282,9 +293,9 @@ impl FieldCursor {
 
                         match *mapping.entry(field.to_owned())
                                       .or_insert(Value::Object(Default::default())) {
-                            Value::Object(ref mut map) => {
-                                if map.insert(key.to_owned(), jval).is_some() {
-                                    err.issues.push(CLIError::Field(FieldError::Duplicate(self.to_string())));
+                            Value::Object(ref mut value_map) => {
+                                if value_map.insert(key.to_owned(), jval).is_some() {
+                                    err.issues.push(CLIError::Field(FieldError::Duplicate(orig_cursor.to_string())));
                                 }
                             }
                             _ => unreachable!()