diff --git a/packages/cli-json-cas/package.json b/packages/cli-json-cas/package.json
index 83eb723..5b47097 100644
--- a/packages/cli-json-cas/package.json
+++ b/packages/cli-json-cas/package.json
@@ -3,7 +3,8 @@
   "version": "0.5.3",
   "type": "module",
   "bin": {
-    "json-cas": "./src/index.ts"
+    "json-cas": "./src/index.ts",
+    "ucas": "./src/index.ts"
   },
   "scripts": {
     "test": "bun test",
diff --git a/packages/cli-json-cas/src/cli.test.ts b/packages/cli-json-cas/src/cli.test.ts
new file mode 100644
index 0000000..4152d8b
--- /dev/null
+++ b/packages/cli-json-cas/src/cli.test.ts
@@ -0,0 +1,33 @@
+import { describe, expect, test } from "bun:test";
+import { resolve } from "node:path";
+
+const pkgPath = resolve(import.meta.dir, "../package.json");
+
+describe("ucas command alias", () => {
+  test("T1: ucas bin entry exists in package.json", async () => {
+    const pkg = await Bun.file(pkgPath).json();
+    expect(pkg.bin.ucas).toBe("./src/index.ts");
+  });
+
+  test("T2: json-cas bin entry is preserved in package.json", async () => {
+    const pkg = await Bun.file(pkgPath).json();
+    expect(pkg.bin["json-cas"]).toBe("./src/index.ts");
+  });
+
+  test("T3: ucas command is executable and shows help", async () => {
+    const entrypoint = resolve(import.meta.dir, "index.ts");
+    const proc = Bun.spawn(["bun", entrypoint, "--help"], {
+      stdout: "pipe",
+      stderr: "pipe",
+    });
+    const exitCode = await proc.exited;
+    const stdout = await new Response(proc.stdout).text();
+    expect(exitCode).toBe(0);
+    expect(stdout.length).toBeGreaterThan(0);
+  });
+
+  test("T4: both commands point to the same entrypoint", async () => {
+    const pkg = await Bun.file(pkgPath).json();
+    expect(pkg.bin.ucas).toBe(pkg.bin["json-cas"]);
+  });
+});