diff --git a/app/vite-plugins/dev-indices/__tests__/manifest.test.ts b/app/vite-plugins/dev-indices/__tests__/manifest.test.ts
index b6ad9259..bf66dc0a 100644
--- a/app/vite-plugins/dev-indices/__tests__/manifest.test.ts
+++ b/app/vite-plugins/dev-indices/__tests__/manifest.test.ts
@@ -95,4 +95,27 @@ describe('manifest', () => {
         expect(() => readFileSync(path + '.tmp')).toThrow();
         rmSync(dir, { recursive: true });
     });
+
+    it('loadManifest throws on corrupt JSON with actionable message', () => {
+        const dir = mkdtempSync(join(tmpdir(), 'dx-'));
+        const path = join(dir, 'm.json');
+        writeFileSync(path, '{not valid json', 'utf8');
+        expect(() => loadManifest(path)).toThrow(/corrupt JSON/);
+        rmSync(dir, { recursive: true });
+    });
+
+    it('loadManifest throws on unsupported version', () => {
+        const dir = mkdtempSync(join(tmpdir(), 'dx-'));
+        const path = join(dir, 'm.json');
+        writeFileSync(path, JSON.stringify({ version: 2, lastId: 0, entries: {}, deleted: {} }), 'utf8');
+        expect(() => loadManifest(path)).toThrow(/version 2 unsupported/);
+        rmSync(dir, { recursive: true });
+    });
+
+    it('markDeleted is a no-op for unknown ids (does not throw)', () => {
+        const m = createEmpty();
+        expect(() => markDeleted(m, 9999)).not.toThrow();
+        expect(m.deleted['9999']).toBeUndefined();
+        expect(m.lastId).toBe(0);
+    });
 });
diff --git a/app/vite-plugins/dev-indices/manifest.ts b/app/vite-plugins/dev-indices/manifest.ts
index f6d8058c..8f490932 100644
--- a/app/vite-plugins/dev-indices/manifest.ts
+++ b/app/vite-plugins/dev-indices/manifest.ts
@@ -56,6 +56,7 @@ export function addEntry(manifest: Manifest, entry: ManifestEntry): number {
 export function markDeleted(manifest: Manifest, id: number): void {
     const key = String(id);
     const entry = manifest.entries[key];
+    // no-op if id was never added or already deleted — defensive, callers should not rely on this
     if (!entry) return;
     manifest.deleted[key] = {
         lastSignature: entry.signature,
diff --git a/app/vite-plugins/dev-indices/vitest.config.ts b/app/vite-plugins/dev-indices/vitest.config.ts
index da3292a6..b7ca48d0 100644
--- a/app/vite-plugins/dev-indices/vitest.config.ts
+++ b/app/vite-plugins/dev-indices/vitest.config.ts
@@ -3,7 +3,6 @@ import { defineConfig } from 'vitest/config';
 // Vitest config for dev-indices Vite plugin (pure Node, no jsdom)
 export default defineConfig({
     test: {
-        globals: true,
         environment: 'node',
         include: ['__tests__/**/*.{test,spec}.ts'],
     },