diff --git a/src/tests/headless-query-extension-path.test.ts b/src/tests/headless-query-extension-path.test.ts
new file mode 100644
index 000000000..499509187
--- /dev/null
+++ b/src/tests/headless-query-extension-path.test.ts
@@ -0,0 +1,28 @@
+/**
+ * Regression test for #3471: headless-query must load extensions from
+ * the synced agent directory, not directly from src/resources/.
+ */
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import { join, dirname } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+test("headless-query resolves from agent extensions dir (#3471)", () => {
+  const src = readFileSync(join(__dirname, "..", "headless-query.ts"), "utf-8");
+  assert.ok(
+    src.includes("agentExtensionsDir") || src.includes(".gsd/agent"),
+    "headless-query must resolve from synced agent directory",
+  );
+});
+
+test("cli.ts calls initResources before headless (#3471)", () => {
+  const src = readFileSync(join(__dirname, "..", "cli.ts"), "utf-8");
+  const headlessBlock = src.slice(src.indexOf("gsd headless"));
+  const initIdx = headlessBlock.indexOf("initResources");
+  const runIdx = headlessBlock.indexOf("runHeadless");
+  assert.ok(initIdx !== -1, "initResources must be called before headless");
+  assert.ok(initIdx < runIdx, "initResources must come before runHeadless");
+});