diff --git a/src/plot_api/plot_schema.js b/src/plot_api/plot_schema.js
index 54e2b5aab29..73aca869bc8 100644
--- a/src/plot_api/plot_schema.js
+++ b/src/plot_api/plot_schema.js
@@ -63,7 +63,7 @@ exports.get = function() {
     return {
         defs: {
             valObjects: valObjectMeta,
-            metaKeys: UNDERSCORE_ATTRS.concat(['description', 'editType', 'impliedEdits']),
+            metaKeys: UNDERSCORE_ATTRS.concat(['description', 'role', 'editType', 'impliedEdits']),
             editType: {
                 traces: editTypes.traces,
                 layout: editTypes.layout
@@ -600,14 +600,14 @@ function getFramesAttributes() {
 }
 
 function formatAttributes(attrs) {
-    mergeValType(attrs);
+    mergeValTypeAndRole(attrs);
     formatArrayContainers(attrs);
     stringify(attrs);
 
     return attrs;
 }
 
-function mergeValType(attrs) {
+function mergeValTypeAndRole(attrs) {
     function makeSrcAttr(attrName) {
         return {
             valType: 'string',
@@ -621,13 +621,13 @@ function mergeValType(attrs) {
 
     function callback(attr, attrName, attrs) {
         if(exports.isValObject(attr)) {
-            if(attr.valType === 'data_array') {
-                // all 'data_array' attrs have a corresponding 'src' attr
-                attrs[attrName + 'src'] = makeSrcAttr(attrName);
-            } else if(attr.arrayOk === true) {
-                // all 'arrayOk' attrs have a corresponding 'src' attr
+            if(attr.arrayOk === true || attr.valType === 'data_array') {
+                // all 'arrayOk' and 'data_array' attrs have a corresponding 'src' attr
                 attrs[attrName + 'src'] = makeSrcAttr(attrName);
             }
+        } else if(isPlainObject(attr)) {
+            // all attrs container objects get role 'object'
+            attr.role = 'object';
         }
     }
 
@@ -646,6 +646,7 @@ function formatArrayContainers(attrs) {
 
         attrs[attrName] = { items: {} };
         attrs[attrName].items[itemName] = attr;
+        attrs[attrName].role = 'object';
     }
 
     exports.crawl(attrs, callback);
diff --git a/tasks/compress_attributes.js b/tasks/compress_attributes.js
index b2f43e7e5d4..aa1ae1df7d9 100644
--- a/tasks/compress_attributes.js
+++ b/tasks/compress_attributes.js
@@ -48,6 +48,7 @@ module.exports = function() {
                 .replace(makeJoinedArrayRegex('description'), '')
                 .replace(makeArrayRegex('requiredOpts'), '')
                 .replace(makeArrayRegex('otherOpts'), '')
+                .replace(makeStringRegex('role'), '')
                 .replace(makeStringRegex('hrName'), '')
         );
         done();
diff --git a/test/jasmine/bundle_tests/plotschema_test.js b/test/jasmine/bundle_tests/plotschema_test.js
index 3d749abe160..59cdf9ca0f1 100644
--- a/test/jasmine/bundle_tests/plotschema_test.js
+++ b/test/jasmine/bundle_tests/plotschema_test.js
@@ -25,6 +25,7 @@ describe('plot schema', function() {
     var isPlainObject = Lib.isPlainObject;
 
     var VALTYPES = Object.keys(valObjects);
+    var formerRoles = ['info', 'style', 'data'];
     var editType = plotSchema.defs.editType;
 
     function assertTraceSchema(callback) {
@@ -72,6 +73,27 @@ describe('plot schema', function() {
         );
     });
 
+    it('all attributes should not have a former `role`', function() {
+        assertPlotSchema(
+            function(attr) {
+                if(isValObject(attr)) {
+                    expect(formerRoles.indexOf(attr.role) === -1).toBe(true, attr);
+                    expect(attr.role).toBeUndefined(attr);
+                }
+            }
+        );
+    });
+
+    it('all nested objects should have the *object* `role`', function() {
+        assertPlotSchema(
+            function(attr, attrName) {
+                if(!isValObject(attr) && isPlainObject(attr) && attrName !== 'items') {
+                    expect(attr.role === 'object').toBe(true);
+                }
+            }
+        );
+    });
+
     it('all attributes should have the required options', function() {
         assertPlotSchema(
             function(attr) {
@@ -94,7 +116,7 @@ describe('plot schema', function() {
                     var opts = valObject.requiredOpts
                         .concat(valObject.otherOpts)
                         .concat([
-                            'valType', 'description',
+                            'valType', 'description', 'role',
                             'editType', 'impliedEdits', 'anim',
                             '_compareAsJSON', '_noTemplating'
                         ]);
@@ -164,8 +186,13 @@ describe('plot schema', function() {
 
             // N.B. the specs below must be satisfied for plotly.py
             expect(isPlainObject(itemsObj)).toBe(true);
+            expect(itemsObj.role).toBeUndefined();
             expect(Object.keys(itemsObj).length).toEqual(1);
             expect(isPlainObject(itemObj)).toBe(true);
+            expect(itemObj.role).toBe('object');
+
+            var role = np.get().role;
+            expect(role).toEqual('object');
         });
     });
 
@@ -197,7 +224,7 @@ describe('plot schema', function() {
         );
     });
 
-    it('deprecated attributes should have a `valType`', function() {
+    it('deprecated attributes should have a `valType` and not any former roles', function() {
         var DEPRECATED = '_deprecated';
 
         assertPlotSchema(
@@ -206,8 +233,10 @@ describe('plot schema', function() {
                     Object.keys(attr[DEPRECATED]).forEach(function(dAttrName) {
                         var dAttr = attr[DEPRECATED][dAttrName];
 
-                        expect(VALTYPES.indexOf(dAttr.valType) !== -1)
-                            .toBe(true, attrString + ': ' + dAttrName);
+                        var msg = attrString + ': ' + dAttrName;
+                        expect(VALTYPES.indexOf(dAttr.valType) !== -1).toBe(true, msg);
+                        expect(formerRoles.indexOf(dAttr.role) === -1).toBe(true, msg);
+                        expect(dAttr.role).toBeUndefined(msg);
                     });
                 }
             }
@@ -289,13 +318,15 @@ describe('plot schema', function() {
         expect(plotSchema.defs.metaKeys)
             .toEqual([
                 '_isSubplotObj', '_isLinkedToArray', '_arrayAttrRegexps',
-                '_deprecated', 'description', 'editType', 'impliedEdits'
+                '_deprecated', 'description', 'role', 'editType', 'impliedEdits'
             ]);
     });
 
     it('should list the correct frame attributes', function() {
         expect(plotSchema.frames).toBeDefined();
+        expect(plotSchema.frames.role).toEqual('object');
         expect(plotSchema.frames.items.frames_entry).toBeDefined();
+        expect(plotSchema.frames.items.frames_entry.role).toEqual('object');
     });
 
     it('should list config attributes', function() {
@@ -439,7 +470,7 @@ describe('getTraceValObject', function() {
         // it still returns the attribute itself - but maybe we should only do this
         // for valType: any? (or data_array/arrayOk with just an index)
         [
-            'valType', 'dflt', 'description', 'arrayOk',
+            'valType', 'dflt', 'role', 'description', 'arrayOk',
             'editType', 'min', 'max', 'values'
         ].forEach(function(prop) {
             expect(getTraceValObject({}, ['x', prop]))