diff --git a/frontend/__mocks__/hostMock.ts b/frontend/__mocks__/hostMock.ts
index b9b36b248e..37b5f826bd 100644
--- a/frontend/__mocks__/hostMock.ts
+++ b/frontend/__mocks__/hostMock.ts
@@ -1,5 +1,9 @@
-import { IHost, IHostResponse } from "interfaces/host";
+import { IHost } from "interfaces/host";
 import { IHostMdmProfile } from "interfaces/mdm";
+import { pick } from "lodash";
+
+import { normalizeEmptyValues } from "utilities/helpers";
+import { HOST_SUMMARY_DATA } from "utilities/constants";
 
 const DEFAULT_HOST_PROFILE_MOCK: IHostMdmProfile = {
   profile_uuid: "123-abc",
@@ -35,7 +39,7 @@ const DEFAULT_HOST_MOCK: IHost = {
   platform: "ubuntu",
   osquery_version: "4.9.0",
   orbit_version: "1.22.0",
-  fleet_desktop_version: "1.22.0",
+  fleet_desktop_version: "1.22.1",
   os_version: "Ubuntu 18.4.0",
   build: "",
   platform_like: "debian",
@@ -106,4 +110,10 @@ const createMockHost = (overrides?: Partial<IHost>): IHost => {
 
 export const createMockHostResponse = { host: createMockHost() };
 
+export const createMockHostSummary = (overrides?: Partial<IHost>) => {
+  return normalizeEmptyValues(
+    pick(createMockHost(overrides), HOST_SUMMARY_DATA)
+  );
+};
+
 export default createMockHost;
diff --git a/frontend/pages/hosts/details/cards/HostSummary/HostSummary.tests.tsx b/frontend/pages/hosts/details/cards/HostSummary/HostSummary.tests.tsx
new file mode 100644
index 0000000000..da1258a28e
--- /dev/null
+++ b/frontend/pages/hosts/details/cards/HostSummary/HostSummary.tests.tsx
@@ -0,0 +1,143 @@
+import React from "react";
+import { noop } from "lodash";
+import { screen } from "@testing-library/react";
+import { createCustomRenderer } from "test/test-utils";
+
+import createMockUser from "__mocks__/userMock";
+import { createMockHostSummary } from "__mocks__/hostMock";
+
+import HostSummary from "./HostSummary";
+
+describe("Host Actions Dropdown", () => {
+  describe("Agent data", () => {
+    it("with all info present, render Agent header with orbit_version and tooltip with all 3 data points", async () => {
+      const render = createCustomRenderer({
+        context: {
+          app: {
+            isPremiumTier: true,
+            isGlobalAdmin: true,
+            currentUser: createMockUser(),
+          },
+        },
+      });
+      const summaryData = createMockHostSummary();
+      const orbitVersion = summaryData.orbit_version as string;
+      const osqueryVersion = summaryData.osquery_version as string;
+      const fleetdVersion = summaryData.fleet_desktop_version as string;
+
+      const { user } = render(
+        <HostSummary
+          summaryData={summaryData}
+          showRefetchSpinner={false}
+          onRefetchHost={noop}
+          renderActionButtons={() => null}
+        />
+      );
+
+      expect(screen.getByText("Agent")).toBeInTheDocument();
+      await user.hover(screen.getByText(new RegExp(orbitVersion, "i")));
+
+      expect(
+        screen.getByText(new RegExp(osqueryVersion, "i"))
+      ).toBeInTheDocument();
+      expect(
+        screen.getByText(new RegExp(fleetdVersion, "i"))
+      ).toBeInTheDocument();
+    });
+
+    it("omit fleet desktop from tooltip if no fleet desktop version", async () => {
+      const render = createCustomRenderer({
+        context: {
+          app: {
+            isPremiumTier: true,
+            isGlobalAdmin: true,
+            currentUser: createMockUser(),
+          },
+        },
+      });
+      const summaryData = createMockHostSummary({
+        fleet_desktop_version: null,
+      });
+      const orbitVersion = summaryData.orbit_version as string;
+      const osqueryVersion = summaryData.osquery_version as string;
+
+      const { user } = render(
+        <HostSummary
+          summaryData={summaryData}
+          showRefetchSpinner={false}
+          onRefetchHost={noop}
+          renderActionButtons={() => null}
+        />
+      );
+
+      expect(screen.getByText("Agent")).toBeInTheDocument();
+      await user.hover(screen.getByText(new RegExp(orbitVersion, "i")));
+
+      expect(
+        screen.getByText(new RegExp(osqueryVersion, "i"))
+      ).toBeInTheDocument();
+      expect(screen.queryByText(/Fleet desktop:/i)).not.toBeInTheDocument();
+    });
+
+    it("for Chromebooks, render Agent header with osquery_version that is the fleetd chrome version and no tooltip", async () => {
+      const render = createCustomRenderer({
+        context: {
+          app: {
+            isPremiumTier: true,
+            isGlobalAdmin: true,
+            currentUser: createMockUser(),
+          },
+        },
+      });
+      const summaryData = createMockHostSummary({
+        platform: "chrome",
+        osquery_version: "fleetd-chrome 1.2.0",
+      });
+
+      const fleetdChromeVersion = summaryData.osquery_version as string;
+
+      const { user } = render(
+        <HostSummary
+          summaryData={summaryData}
+          showRefetchSpinner={false}
+          onRefetchHost={noop}
+          renderActionButtons={() => null}
+        />
+      );
+
+      expect(screen.getByText("Agent")).toBeInTheDocument();
+      await user.hover(screen.getByText(new RegExp(fleetdChromeVersion, "i")));
+      expect(screen.queryByText("Osquery")).not.toBeInTheDocument();
+    });
+    it("for non-Chromebooks with no orbit_version, render Osquery header with osquery_version and no tooltip", async () => {
+      const render = createCustomRenderer({
+        context: {
+          app: {
+            isPremiumTier: true,
+            isGlobalAdmin: true,
+            currentUser: createMockUser(),
+          },
+        },
+      });
+      const summaryData = createMockHostSummary({
+        orbit_version: null,
+      });
+
+      const osqueryVersion = summaryData.osquery_version as string;
+
+      const { user } = render(
+        <HostSummary
+          summaryData={summaryData}
+          showRefetchSpinner={false}
+          onRefetchHost={noop}
+          renderActionButtons={() => null}
+        />
+      );
+
+      expect(screen.getByText("Osquery")).toBeInTheDocument();
+      await user.hover(screen.getByText(new RegExp(osqueryVersion, "i")));
+      expect(screen.queryByText(/Orbit/i)).not.toBeInTheDocument();
+      expect(screen.queryByText(/Fleet desktop/i)).not.toBeInTheDocument();
+    });
+  });
+});