From 1c200a2e0dc372ea48aad1415df3cb219ba06244 Mon Sep 17 00:00:00 2001
From: Cursor Agent <cursoragent@cursor.com>
Date: Mon, 28 Sep 2026 16:37:19 +0000
Subject: [PATCH] Reject an unknown act domain before spawning the rail CLI.

runDecide already refused a domain other than refund or inventory. runAct passed any other value through as the demo command.
---
 CHANGELOG.md        |  3 +++
 bin/aas.mjs         |  3 +++
 test/stack.test.mjs | 13 +++++++++++++
 3 files changed, 19 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 402fd4b..9853f33 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,9 @@ project adheres to [Semantic Versioning](https://semver.org/).
 - Playwright setup note in the Quick start section of `README.md`.
 
 ### Fixed
+- `runAct` now rejects a domain other than `refund` or `inventory` before it
+  spawns the rail CLI. Any other value was passed through as the demo
+  command.
 - An act result that explicitly reports `fault: null` is stored as null. The
   report used to replace that null with the requested fault, so a cleared
   fault was recorded as `duplicate` when `--fault duplicate` was passed.
diff --git a/bin/aas.mjs b/bin/aas.mjs
index 82a2489..c7fa65e 100644
--- a/bin/aas.mjs
+++ b/bin/aas.mjs
@@ -675,6 +675,9 @@ export function runAct(
     domain = "refund",
   } = {},
 ) {
+  if (!DEMO_DOMAINS.has(domain)) {
+    throw new Error("act domain must be refund or inventory");
+  }
   const crctl = join(depsDir, "consequence-rail", "cmd", "crctl.js");
   if (runner === runCapture && !existsSync(crctl)) {
     throw missingChildTool("act CLI (deps/consequence-rail/cmd/crctl.js)");
diff --git a/test/stack.test.mjs b/test/stack.test.mjs
index 9b2d8c2..b45cc80 100644
--- a/test/stack.test.mjs
+++ b/test/stack.test.mjs
@@ -1838,6 +1838,19 @@ test("runAct targets the requested rail demo domain", () => {
   assert.equal(seen[0][2], "inventory");
 });
 
+test("runAct rejects an unknown domain before spawning the rail CLI", () => {
+  let called = false;
+  assert.throws(() => runAct("none", {
+    depsDir: "deps",
+    domain: "payments",
+    runner: () => {
+      called = true;
+      return { status: 0, stdout: '{"outcome":"settled","state":"CLOSED","fault":"none","action_id":"a"}\n', stderr: "", error: null };
+    },
+  }), /act domain must be refund or inventory/);
+  assert.equal(called, false);
+});
+
 test("runDecide rejects an unknown domain instead of loading the refund policy", () => {
   let called = false;
   assert.throws(() => runDecide("unused", {