diff --git a/src/feature-flags/properties.test.ts b/src/feature-flags/properties.test.ts
new file mode 100644
index 000000000..66e5ca979
--- /dev/null
+++ b/src/feature-flags/properties.test.ts
@@ -0,0 +1,58 @@
+import test from "ava";
+import * as sinon from "sinon";
+
+import * as api from "../api-client";
+import { getRunnerLogger } from "../logging";
+import { parseRepositoryNwo } from "../repository";
+import { setupTests } from "../testing-utils";
+
+import * as properties from "./properties";
+
+setupTests(test);
+
+test("loadPropertiesFromApi throws if response data is not an array", async (t) => {
+  sinon.stub(api, "getRepositoryProperties").resolves({
+    headers: {},
+    status: 200,
+    url: "",
+    data: {},
+  });
+  const logger = getRunnerLogger(true);
+  const mockRepositoryNwo = parseRepositoryNwo("owner/repo");
+  await t.throwsAsync(
+    properties.loadPropertiesFromApi(logger, mockRepositoryNwo),
+  );
+});
+
+test("loadPropertiesFromApi throws if response data contains unexpected objects", async (t) => {
+  sinon.stub(api, "getRepositoryProperties").resolves({
+    headers: {},
+    status: 200,
+    url: "",
+    data: [{}],
+  });
+  const logger = getRunnerLogger(true);
+  const mockRepositoryNwo = parseRepositoryNwo("owner/repo");
+  await t.throwsAsync(
+    properties.loadPropertiesFromApi(logger, mockRepositoryNwo),
+  );
+});
+
+test("loadPropertiesFromApi loads known properties", async (t) => {
+  sinon.stub(api, "getRepositoryProperties").resolves({
+    headers: {},
+    status: 200,
+    url: "",
+    data: [
+      { property_name: "github-codeql-extra-queries", value: "+queries" },
+      { property_name: "unknown-property", value: "something" },
+    ] satisfies properties.RepositoryProperty[],
+  });
+  const logger = getRunnerLogger(true);
+  const mockRepositoryNwo = parseRepositoryNwo("owner/repo");
+  const response = await properties.loadPropertiesFromApi(
+    logger,
+    mockRepositoryNwo,
+  );
+  t.deepEqual(response, { "github-codeql-extra-queries": "+queries" });
+});