diff --git a/tests/unit/tasks/complete-reaction.test.ts b/tests/unit/tasks/complete-reaction.test.ts
new file mode 100644
index 0000000..ecc293d
--- /dev/null
+++ b/tests/unit/tasks/complete-reaction.test.ts
@@ -0,0 +1,158 @@
+import { describe, it, expect, beforeAll, afterAll, beforeEach } from 'bun:test';
+import { Database } from 'bun:sqlite';
+import { initializeDatabase } from '../../../src/db';
+import { TaskService } from '../../../src/tasks/service';
+import { ResponseQueue } from '../../../src/services/response-queue';
+import { AllowedGroups } from '../../../src/services/allowed-groups';
+
+function toIsoSql(d: Date): string {
+  return d.toISOString().replace('T', ' ').replace('Z', '');
+}
+
+describe('TaskService - reacción ✅ al completar (Fase 2)', () => {
+  let memdb: Database;
+  let envBackup: Record<string, string | undefined>;
+
+  beforeAll(() => {
+    envBackup = { ...process.env };
+    memdb = new Database(':memory:');
+    initializeDatabase(memdb);
+    (TaskService as any).dbInstance = memdb;
+    (ResponseQueue as any).dbInstance = memdb;
+    (AllowedGroups as any).dbInstance = memdb;
+  });
+
+  afterAll(() => {
+    process.env = envBackup;
+    try { memdb.close(); } catch {}
+  });
+
+  beforeEach(() => {
+    process.env.NODE_ENV = 'test';
+    process.env.REACTIONS_ENABLED = 'true';
+    process.env.REACTIONS_SCOPE = 'groups';
+    process.env.REACTIONS_TTL_DAYS = '14';
+    process.env.GROUP_GATING_MODE = 'enforce';
+
+    memdb.exec(`
+      DELETE FROM response_queue;
+      DELETE FROM task_assignments;
+      DELETE FROM tasks;
+      DELETE FROM users;
+      DELETE FROM task_origins;
+      DELETE FROM allowed_groups;
+    `);
+  });
+
+  it('enqueuea ✅ al completar una tarea con task_origins dentro de TTL y grupo allowed', async () => {
+    const groupId = 'grp-1@g.us';
+    AllowedGroups.setStatus(groupId, 'allowed');
+
+    const taskId = TaskService.createTask({
+      description: 'Prueba ✅',
+      due_date: null,
+      group_id: groupId,
+      created_by: '600111222'
+    });
+
+    // Origen reciente (dentro de TTL)
+    const msgId = 'MSG-OK-1';
+    memdb.prepare(`
+      INSERT INTO task_origins (task_id, chat_id, message_id, created_at)
+      VALUES (?, ?, ?, ?)
+    `).run(taskId, groupId, msgId, toIsoSql(new Date()));
+
+    const res = TaskService.completeTask(taskId, '600111222');
+    expect(res.status).toBe('updated');
+
+    const row = memdb.prepare(`SELECT id, recipient, metadata FROM response_queue ORDER BY id DESC LIMIT 1`).get() as any;
+    expect(row).toBeTruthy();
+    expect(String(row.recipient)).toBe(groupId);
+
+    const meta = JSON.parse(String(row.metadata || '{}'));
+    expect(meta.kind).toBe('reaction');
+    expect(meta.emoji).toBe('✅');
+    expect(meta.chatId).toBe(groupId);
+    expect(meta.messageId).toBe(msgId);
+  });
+
+  it('no encola ✅ si el origen está fuera de TTL', async () => {
+    const groupId = 'grp-2@g.us';
+    AllowedGroups.setStatus(groupId, 'allowed');
+
+    // TTL 7 días para forzar expiración
+    process.env.REACTIONS_TTL_DAYS = '7';
+
+    const taskId = TaskService.createTask({
+      description: 'Fuera TTL',
+      due_date: null,
+      group_id: groupId,
+      created_by: '600111222'
+    });
+
+    const msgId = 'MSG-OLD-1';
+    const old = new Date(Date.now() - 8 * 24 * 60 * 60 * 1000); // 8 días atrás
+    memdb.prepare(`
+      INSERT INTO task_origins (task_id, chat_id, message_id, created_at)
+      VALUES (?, ?, ?, ?)
+    `).run(taskId, groupId, msgId, toIsoSql(old));
+
+    const res = TaskService.completeTask(taskId, '600111222');
+    expect(res.status).toBe('updated');
+
+    const cnt = memdb.prepare(`SELECT COUNT(*) AS c FROM response_queue`).get() as any;
+    expect(Number(cnt.c)).toBe(0);
+  });
+
+  it('idempotencia: completar dos veces encola solo un ✅', async () => {
+    const groupId = 'grp-3@g.us';
+    AllowedGroups.setStatus(groupId, 'allowed');
+
+    const taskId = TaskService.createTask({
+      description: 'Idempotencia ✅',
+      due_date: null,
+      group_id: groupId,
+      created_by: '600111222'
+    });
+
+    const msgId = 'MSG-IDEMP-1';
+    memdb.prepare(`
+      INSERT INTO task_origins (task_id, chat_id, message_id, created_at)
+      VALUES (?, ?, ?, ?)
+    `).run(taskId, groupId, msgId, toIsoSql(new Date()));
+
+    const r1 = TaskService.completeTask(taskId, '600111222');
+    const r2 = TaskService.completeTask(taskId, '600111222');
+    expect(r1.status === 'updated' || r1.status === 'already').toBe(true);
+    expect(r2.status === 'updated' || r2.status === 'already').toBe(true);
+
+    const rows = memdb.query(`SELECT metadata FROM response_queue`).all() as any[];
+    expect(rows.length).toBe(1);
+    const meta = JSON.parse(String(rows[0].metadata || '{}'));
+    expect(meta.emoji).toBe('✅');
+  });
+
+  it('enforce: grupo no allowed → no encola ✅', async () => {
+    const groupId = 'grp-4@g.us';
+    // Estado por defecto 'pending' (no allowed)
+
+    const taskId = TaskService.createTask({
+      description: 'No allowed',
+      due_date: null,
+      group_id: groupId,
+      created_by: '600111222'
+    });
+
+    const msgId = 'MSG-NO-ALLOW-1';
+    memdb.prepare(`
+      INSERT INTO task_origins (task_id, chat_id, message_id, created_at)
+      VALUES (?, ?, ?, ?)
+    `).run(taskId, groupId, msgId, toIsoSql(new Date()));
+
+    const res = TaskService.completeTask(taskId, '600111222');
+    expect(res.status === 'updated' || res.status === 'already').toBe(true);
+
+    const cnt = memdb.prepare(`SELECT COUNT(*) AS c FROM response_queue`).get() as any;
+    expect(Number(cnt.c)).toBe(0);
+  });
+});