diff --git a/scripts/check-container.mjs b/scripts/check-container.mjs
index 0955b14..3449331 100644
--- a/scripts/check-container.mjs
+++ b/scripts/check-container.mjs
@@ -43,6 +43,13 @@ async function request(path, options) {
   assert.ok(response.ok, `${path}: HTTP ${response.status}`);
   return response;
 }
+async function expectServices(sfu, natPrediction) {
+  const capabilities = await (await request("/api/capabilities")).json();
+  // Capability metadata is extensible. This gate checks configured services,
+  // not the absence of other compatible capabilities.
+  assert.equal(capabilities.sfu, sfu);
+  assert.equal(capabilities.natPrediction, natPrediction);
+}
 async function binding(port) {
   const socket = createSocket("udp4");
   const packet = Buffer.alloc(20);
@@ -79,7 +86,7 @@ try {
   assert.match(compose("run", "--rm", "--no-deps", "piik", "--check-config"), /config=ok/);
   compose("up", "-d", "--pull", "never");
   await until(async () => assert.deepEqual(await (await request("/healthz")).json(), { status: "ok" }), "ready");
-  assert.deepEqual(await (await request("/api/capabilities")).json(), { sfu: false, natPrediction: false });
+  await expectServices(false, false);
   assert.equal((await (await request("/api/site-access")).json()).required, false);
   const html = await (await request("/")).text();
   const asset = html.match(/src="(\/assets\/index-[A-Za-z0-9_-]+\.js)"/)?.[1];
@@ -101,7 +108,7 @@ try {
   // Recreate with optional services on the same persistent room volume.
   writeFileSync(join(workspace, ".env"), `${sample}\nSFU_UDP_PORT=7882\nSFU_PUBLIC_IP=127.0.0.1\nNAT_PREDICTION_ENABLED=true\nPIIK_DEBUG=server\n`);
   compose("up", "-d", "--force-recreate", "--pull", "never");
-  await until(async () => assert.deepEqual(await (await request("/api/capabilities")).json(), { sfu: true, natPrediction: true }), "optional services");
+  await until(() => expectServices(true, true), "optional services");
   await request(`/api/rooms/${room.roomId}/access`, {
     method: "POST",
     headers: { Origin: "https://share.example.com", Authorization: `Bearer ${room.hostToken}`, "Content-Type": "application/json" },
diff --git a/scripts/release-version.mjs b/scripts/release-version.mjs
index 8a4a2a5..7d8ef1a 100644
--- a/scripts/release-version.mjs
+++ b/scripts/release-version.mjs
@@ -20,7 +20,7 @@ const nonProductPaths = [
   "cmd/**/*.md", "internal/**/*.md", "native/**/*.md", "src/**/*.md",
   ".github/ISSUE_TEMPLATE/**", ".github/pull_request_template.md", ".github/workflows/website.yml",
   "scripts/build-website.mjs", "scripts/update-website-hero.mjs", "scripts/check-website-film.js",
-  "scripts/check-docs.mjs", "scripts/markdown-slug.mjs", "scripts/check-project-state.*", "scripts/install-hooks.*",
+  "scripts/check-docs.mjs", "scripts/check-container.mjs", "scripts/markdown-slug.mjs", "scripts/check-project-state.*", "scripts/install-hooks.*",
   "scripts/required-project-paths.txt", "scripts/tsconfig.json",
   "scripts/release-*.mjs", "scripts/publish-release.mjs", "scripts/publish-container.mjs", "scripts/mirror-release.mjs",
   "scripts/*-gate.*", "scripts/*-probe.*", "scripts/browser-*", "scripts/encoded-*",
diff --git a/tests/release-automation.test.ts b/tests/release-automation.test.ts
index ee367b1..6519cae 100644
--- a/tests/release-automation.test.ts
+++ b/tests/release-automation.test.ts
@@ -90,7 +90,7 @@ describe("release automation", () => {
       expect(plan()).toMatchObject({ version: "v1.0.0", publish: true });
       for (const path of ["site/film/art.js", "site/docs/package.json", "site/docs/package-lock.json",
         "site/docs/.vitepress/config.mjs", "docs/guide/troubleshooting.md", "docs/deployment.md", "README.zh-CN.md",
-        "scripts/build-website.mjs", "scripts/check-docs.mjs", "scripts/markdown-slug.mjs", "scripts/release-notes.mjs",
+        "scripts/build-website.mjs", "scripts/check-docs.mjs", "scripts/check-container.mjs", "scripts/markdown-slug.mjs", "scripts/release-notes.mjs",
         "scripts/publish-container.mjs",
         "scripts/app-gate-endpoint.ts", "scripts/client-gate-endpoint.ts",
         "tests/room.test.ts", ".agents/skills/ponytail/SKILL.md", ".github/workflows/website.yml"]) {