diff --git a/tests/theme.test.ts b/tests/theme.test.ts
new file mode 100644
index 0000000..e3e5754
--- /dev/null
+++ b/tests/theme.test.ts
@@ -0,0 +1,24 @@
+import { describe, expect, it } from "vitest";
+import { autonomyColor, theme } from "../src/tui/lib/theme.js";
+
+describe("theme", () => {
+  describe("autonomyColor", () => {
+    it('returns theme.down for "auto"', () => {
+      expect(autonomyColor("auto")).toBe(theme.down);
+    });
+
+    it('returns theme.flat for "confirm"', () => {
+      expect(autonomyColor("confirm")).toBe(theme.flat);
+    });
+
+    it('returns theme.up for "off"', () => {
+      expect(autonomyColor("off")).toBe(theme.up);
+    });
+
+    it('returns theme.up for any other string', () => {
+      expect(autonomyColor("unknown")).toBe(theme.up);
+      expect(autonomyColor("manual")).toBe(theme.up);
+      expect(autonomyColor("")).toBe(theme.up);
+    });
+  });
+});