diff --git a/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.scss b/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.scss
index d7740724204a7..529fb9c4bd63e 100644
--- a/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.scss
+++ b/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.scss
@@ -15,3 +15,11 @@
     margin-top: $euiSizeXS;
   }
 }
+
+.appSearchNavIcons {
+  // EUI override
+  &.euiFlexItem {
+    flex-grow: 0;
+    flex-direction: row;
+  }
+}
diff --git a/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.test.tsx b/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.test.tsx
index 43dc592660564..4efbf88d1957f 100644
--- a/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.test.tsx
+++ b/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.test.tsx
@@ -9,7 +9,7 @@ import { unmountHandler } from '../../../__mocks__/shallow_useeffect.mock';
 import { setMockValues, setMockActions } from '../../../__mocks__/kea.mock';
 
 import React from 'react';
-import { shallow, mount } from 'enzyme';
+import { shallow } from 'enzyme';
 import { Switch, Redirect, useParams } from 'react-router-dom';
 import { EuiBadge } from '@elastic/eui';
 
@@ -82,106 +82,153 @@ describe('EngineRouter', () => {
 });
 
 describe('EngineNav', () => {
+  const values = { myRole: {}, engineName: 'some-engine', dataLoading: false, engine: {} };
+
   beforeEach(() => {
-    (useParams as jest.Mock).mockReturnValue({ engineName: 'some-engine' });
+    setMockValues(values);
+  });
+
+  it('does not render if async data is still loading', () => {
+    setMockValues({ ...values, dataLoading: true });
+    const wrapper = shallow(<EngineNav />);
+    expect(wrapper.isEmptyRender()).toBe(true);
   });
 
   it('does not render without an engine name', () => {
-    setMockValues({ myRole: {} });
-    (useParams as jest.Mock).mockReturnValue({ engineName: '' });
+    setMockValues({ ...values, engineName: '' });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.isEmptyRender()).toBe(true);
   });
 
-  it('renders an engine label', () => {
-    setMockValues({ myRole: {} });
-    const wrapper = mount(<EngineNav />);
+  it('renders an engine label and badges', () => {
+    setMockValues({ ...values, isSampleEngine: false, isMetaEngine: false });
+    const wrapper = shallow(<EngineNav />);
+    const label = wrapper.find('[data-test-subj="EngineLabel"]').find('.eui-textTruncate');
+
+    expect(label.text()).toEqual('SOME-ENGINE');
+    expect(wrapper.find(EuiBadge)).toHaveLength(0);
 
-    const label = wrapper.find('[data-test-subj="EngineLabel"]').last();
-    expect(label.text()).toEqual(expect.stringContaining('SOME-ENGINE'));
+    setMockValues({ ...values, isSampleEngine: true });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find(EuiBadge).prop('children')).toEqual('SAMPLE ENGINE');
 
-    // TODO: Test sample & meta engine conditional rendering
-    expect(label.find(EuiBadge).text()).toEqual('SAMPLE ENGINE');
+    setMockValues({ ...values, isMetaEngine: true });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find(EuiBadge).prop('children')).toEqual('META ENGINE');
   });
 
   it('renders a default engine overview link', () => {
-    setMockValues({ myRole: {} });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineOverviewLink"]')).toHaveLength(1);
   });
 
   it('renders an analytics link', () => {
-    setMockValues({ myRole: { canViewEngineAnalytics: true } });
+    setMockValues({ ...values, myRole: { canViewEngineAnalytics: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineAnalyticsLink"]')).toHaveLength(1);
   });
 
   it('renders a documents link', () => {
-    setMockValues({ myRole: { canViewEngineDocuments: true } });
+    setMockValues({ ...values, myRole: { canViewEngineDocuments: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineDocumentsLink"]')).toHaveLength(1);
   });
 
   it('renders a schema link', () => {
-    setMockValues({ myRole: { canViewEngineSchema: true } });
+    setMockValues({ ...values, myRole: { canViewEngineSchema: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineSchemaLink"]')).toHaveLength(1);
+  });
+
+  it('renders schema nav icons', () => {
+    const myRole = { canViewEngineSchema: true };
+    const wrapper = shallow(<EngineNav />);
+
+    setMockValues({ ...values, myRole, hasUnconfirmedSchemaFields: true });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find('[data-test-subj="EngineNavSchemaUnconfirmedFields"]')).toHaveLength(1);
 
-    // TODO: Schema warning icon
+    setMockValues({ ...values, myRole, hasSchemaConflicts: true });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find('[data-test-subj="EngineNavSchemaConflicts"]')).toHaveLength(1);
   });
 
-  // TODO: Unskip when EngineLogic is migrated
-  it.skip('renders a crawler link', () => {
-    setMockValues({ myRole: { canViewEngineCrawler: true } });
+  it('renders a crawler link', () => {
+    const myRole = { canViewEngineCrawler: true };
+    setMockValues({ ...values, myRole });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineCrawlerLink"]')).toHaveLength(1);
 
-    // TODO: Test that the crawler link does NOT show up for meta/sample engines
+    // Does not render for meta engines
+    setMockValues({ ...values, myRole, isMetaEngine: true });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find('[data-test-subj="EngineCrawlerLink"]')).toHaveLength(0);
+
+    // Does not render for sample engine
+    setMockValues({ ...values, myRole, isSampleEngine: true });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find('[data-test-subj="EngineCrawlerLink"]')).toHaveLength(0);
   });
 
-  // TODO: Unskip when EngineLogic is migrated
-  it.skip('renders a meta engine source engines link', () => {
-    setMockValues({ myRole: { canViewMetaEngineSourceEngines: true } });
+  it('renders a meta engine source engines link', () => {
+    const myRole = { canViewMetaEngineSourceEngines: true };
+    setMockValues({ ...values, myRole, isMetaEngine: true });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="MetaEngineEnginesLink"]')).toHaveLength(1);
 
-    // TODO: Test that the crawler link does NOT show up for non-meta engines
+    // Does not render if engine is not a meta-engine
+    setMockValues({ ...values, myRole, isMetaEngine: false });
+    wrapper.setProps({}); // Re-render
+    expect(wrapper.find('[data-test-subj="MetaEngineEnginesLink"]')).toHaveLength(0);
   });
 
   it('renders a relevance tuning link', () => {
-    setMockValues({ myRole: { canManageEngineRelevanceTuning: true } });
+    setMockValues({ ...values, myRole: { canManageEngineRelevanceTuning: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineRelevanceTuningLink"]')).toHaveLength(1);
+  });
+
+  it('renders relevance tuning nav icons', () => {
+    setMockValues({
+      ...values,
+      myRole: { canManageEngineRelevanceTuning: true },
+      engine: {
+        unsearchedUnconfirmedFields: true,
+        invalidBoosts: true,
+      },
+    });
+    const wrapper = shallow(<EngineNav />);
 
-    // TODO: Boost error icon
+    expect(wrapper.find('[data-test-subj="EngineNavRelevanceTuningInvalidBoosts"]')).toHaveLength(1); // prettier-ignore
+    expect(wrapper.find('[data-test-subj="EngineNavRelevanceTuningUnsearchedFields"]')).toHaveLength(1); // prettier-ignore
   });
 
   it('renders a synonyms link', () => {
-    setMockValues({ myRole: { canManageEngineSynonyms: true } });
+    setMockValues({ ...values, myRole: { canManageEngineSynonyms: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineSynonymsLink"]')).toHaveLength(1);
   });
 
   it('renders a curations link', () => {
-    setMockValues({ myRole: { canManageEngineCurations: true } });
+    setMockValues({ ...values, myRole: { canManageEngineCurations: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineCurationsLink"]')).toHaveLength(1);
   });
 
   it('renders a results settings link', () => {
-    setMockValues({ myRole: { canManageEngineResultSettings: true } });
+    setMockValues({ ...values, myRole: { canManageEngineResultSettings: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineResultSettingsLink"]')).toHaveLength(1);
   });
 
   it('renders a Search UI link', () => {
-    setMockValues({ myRole: { canManageEngineSearchUi: true } });
+    setMockValues({ ...values, myRole: { canManageEngineSearchUi: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineSearchUILink"]')).toHaveLength(1);
   });
 
   it('renders an API logs link', () => {
-    setMockValues({ myRole: { canViewEngineApiLogs: true } });
+    setMockValues({ ...values, myRole: { canViewEngineApiLogs: true } });
     const wrapper = shallow(<EngineNav />);
     expect(wrapper.find('[data-test-subj="EngineAPILogsLink"]')).toHaveLength(1);
   });
diff --git a/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.tsx b/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.tsx
index 8c03f59702639..9efb0b7804b86 100644
--- a/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.tsx
+++ b/x-pack/plugins/enterprise_search/public/applications/app_search/components/engine/engine_nav.tsx
@@ -8,7 +8,7 @@ import React, { useEffect } from 'react';
 import { Route, Switch, Redirect, useParams } from 'react-router-dom';
 import { useValues, useActions } from 'kea';
 
-import { EuiText, EuiBadge } from '@elastic/eui';
+import { EuiText, EuiBadge, EuiIcon, EuiFlexGroup, EuiFlexItem } from '@elastic/eui';
 import { i18n } from '@kbn/i18n';
 
 import { SideNavLink, SideNavItem } from '../../../shared/layout';
@@ -48,6 +48,7 @@ import {
 } from './constants';
 
 import { EngineLogic } from './';
+import { EngineDetails } from './types';
 
 import './engine_nav.scss';
 
@@ -114,14 +115,22 @@ export const EngineNav: React.FC = () => {
     },
   } = useValues(AppLogic);
 
-  // TODO: Use EngineLogic
-  const isSampleEngine = true;
-  const isMetaEngine = false;
-  const { engineName } = useParams() as { engineName: string };
-  const engineRoute = engineName && getEngineRoute(engineName);
+  const {
+    engineName,
+    dataLoading,
+    isSampleEngine,
+    isMetaEngine,
+    hasSchemaConflicts,
+    hasUnconfirmedSchemaFields,
+    engine,
+  } = useValues(EngineLogic);
 
+  if (dataLoading) return null;
   if (!engineName) return null;
 
+  const engineRoute = getEngineRoute(engineName);
+  const { invalidBoosts, unsearchedUnconfirmedFields } = engine as Required<EngineDetails>;
+
   return (
     <>
       <SideNavItem className="appSearchNavEngineLabel" data-test-subj="EngineLabel">
@@ -166,8 +175,33 @@ export const EngineNav: React.FC = () => {
           to={getAppSearchUrl(engineRoute + ENGINE_SCHEMA_PATH)}
           data-test-subj="EngineSchemaLink"
         >
-          {SCHEMA_TITLE}
-          {/* TODO: Engine schema warning icon */}
+          <EuiFlexGroup justifyContent="spaceBetween" gutterSize="none">
+            <EuiFlexItem>{SCHEMA_TITLE}</EuiFlexItem>
+            <EuiFlexItem className="appSearchNavIcons">
+              {hasUnconfirmedSchemaFields && (
+                <EuiIcon
+                  type="iInCircle"
+                  color="primary"
+                  title={i18n.translate(
+                    'xpack.enterpriseSearch.appSearch.engine.schema.unconfirmedFields',
+                    { defaultMessage: 'New unconfirmed fields' }
+                  )}
+                  data-test-subj="EngineNavSchemaUnconfirmedFields"
+                />
+              )}
+              {hasSchemaConflicts && (
+                <EuiIcon
+                  type="alert"
+                  color="warning"
+                  title={i18n.translate(
+                    'xpack.enterpriseSearch.appSearch.engine.schema.conflicts',
+                    { defaultMessage: 'Schema conflicts' }
+                  )}
+                  data-test-subj="EngineNavSchemaConflicts"
+                />
+              )}
+            </EuiFlexItem>
+          </EuiFlexGroup>
         </SideNavLink>
       )}
       {canViewEngineCrawler && !isMetaEngine && !isSampleEngine && (
@@ -194,8 +228,33 @@ export const EngineNav: React.FC = () => {
           to={getAppSearchUrl(engineRoute + ENGINE_RELEVANCE_TUNING_PATH)}
           data-test-subj="EngineRelevanceTuningLink"
         >
-          {RELEVANCE_TUNING_TITLE}
-          {/* TODO: invalid boosts error icon */}
+          <EuiFlexGroup justifyContent="spaceBetween" gutterSize="none">
+            <EuiFlexItem>{RELEVANCE_TUNING_TITLE}</EuiFlexItem>
+            <EuiFlexItem className="appSearchNavIcons">
+              {invalidBoosts && (
+                <EuiIcon
+                  type="alert"
+                  color="warning"
+                  title={i18n.translate(
+                    'xpack.enterpriseSearch.appSearch.engine.relevanceTuning.invalidBoosts',
+                    { defaultMessage: 'Invalid boosts' }
+                  )}
+                  data-test-subj="EngineNavRelevanceTuningInvalidBoosts"
+                />
+              )}
+              {unsearchedUnconfirmedFields && (
+                <EuiIcon
+                  type="alert"
+                  color="warning"
+                  title={i18n.translate(
+                    'xpack.enterpriseSearch.appSearch.engine.relevanceTuning.unsearchedFields',
+                    { defaultMessage: 'Unsearched fields' }
+                  )}
+                  data-test-subj="EngineNavRelevanceTuningUnsearchedFields"
+                />
+              )}
+            </EuiFlexItem>
+          </EuiFlexGroup>
         </SideNavLink>
       )}
       {canManageEngineSynonyms && (