diff --git a/package.json b/package.json
index 2b8146635e..6c4dbc5cd6 100644
--- a/package.json
+++ b/package.json
@@ -2,5 +2,10 @@
   "name": "superpowers",
   "version": "5.1.0",
   "type": "module",
-  "main": ".opencode/plugins/superpowers.js"
+  "main": ".opencode/plugins/superpowers.js",
+  "files": [
+    ".opencode/plugins/superpowers.js",
+    "assets/",
+    "skills/"
+  ]
 }
diff --git a/tests/opencode/run-tests.sh b/tests/opencode/run-tests.sh
index d9b100ef0d..909a0319b7 100755
--- a/tests/opencode/run-tests.sh
+++ b/tests/opencode/run-tests.sh
@@ -61,6 +61,7 @@ done
 tests=(
     "test-plugin-loading.sh"
     "test-bootstrap-caching.sh"
+    "test-package-files.sh"
 )
 
 # Integration tests (require OpenCode)
diff --git a/tests/opencode/test-package-files.sh b/tests/opencode/test-package-files.sh
new file mode 100755
index 0000000000..9f68afbfb0
--- /dev/null
+++ b/tests/opencode/test-package-files.sh
@@ -0,0 +1,61 @@
+#!/usr/bin/env bash
+# Test: OpenCode package contents
+# Verifies the git-backed package only ships runtime files.
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+ROOT_DIR="$(cd "$SCRIPT_DIR/../.." && pwd)"
+
+echo "=== Test: OpenCode Package Files ==="
+
+pack_json="$(npm pack --dry-run --json "$ROOT_DIR")"
+
+PACK_JSON="$pack_json" node <<'NODE'
+const data = JSON.parse(process.env.PACK_JSON);
+const files = data[0].files.map((file) => file.path);
+
+const forbiddenPrefixes = [
+  '.claude-plugin/',
+  '.codex-plugin/',
+  '.cursor-plugin/',
+  '.github/',
+  'docs/',
+  'hooks/',
+  'scripts/',
+  'tests/',
+];
+
+const requiredFiles = [
+  '.opencode/plugins/superpowers.js',
+  'assets/app-icon.png',
+  'assets/superpowers-small.svg',
+  'skills/using-superpowers/SKILL.md',
+  'skills/brainstorming/scripts/server.cjs',
+  'package.json',
+  'README.md',
+  'LICENSE',
+];
+
+const failures = [];
+
+for (const prefix of forbiddenPrefixes) {
+  if (files.some((file) => file.startsWith(prefix))) {
+    failures.push(`package includes forbidden path prefix: ${prefix}`);
+  }
+}
+
+for (const file of requiredFiles) {
+  if (!files.includes(file)) {
+    failures.push(`package is missing required file: ${file}`);
+  }
+}
+
+if (failures.length > 0) {
+  for (const failure of failures) console.error(`  [FAIL] ${failure}`);
+  process.exit(1);
+}
+NODE
+
+echo "  [PASS] Package contains only OpenCode runtime files"
+echo ""
+echo "=== All package file tests passed ==="