@codecademy/gamut

Index: package/bin/lib/resolve-plugin-dir.mjs
===================================================================
--- package/bin/lib/resolve-plugin-dir.mjs
+++ package/bin/lib/resolve-plugin-dir.mjs
@@ -0,0 +1,38 @@
+import { stat } from 'node:fs/promises';
+import { dirname, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+/**
+ * Returns the absolute path to the bundled agent-tools directory, or the
+ * value of --plugin-dir if provided.
+ *
+ * @param {string[]} args
+ * @returns {Promise<string>}
+ */
+export async function resolvePluginDir(args) {
+  const override = getFlag(args, '--plugin-dir');
+  if (override) {
+    const abs = resolve(override);
+    const st = await stat(abs).catch(() => null);
+    if (!st?.isDirectory()) {
+      throw new Error(`--plugin-dir path not found: ${abs}`);
+    }
+    return abs;
+  }
+
+  // agent-tools/ is bundled at <package-root>/agent-tools/ relative to bin/lib/
+  return resolve(__dirname, '..', '..', 'agent-tools');
+}
+
+/**
+ * @param {string[]} argv
+ * @param {string} flag
+ * @param {string} [fallback]
+ * @returns {string | undefined}
+ */
+export function getFlag(argv, flag, fallback) {
+  const idx = argv.indexOf(flag);
+  return idx !== -1 ? argv[idx + 1] : fallback;
+}