Caching

After the agent explored your app, TestDriver keeps what it found. TestDriver caches each element that the AI vision agent finds. It uses a vision fingerprint. This is a perceptual hash of the screen state at the element location. On the next run, TestDriver matches against that cache. It does not call the AI again. Tests that pass replay quickly, in the same way each time, and at a low cost.

This learning makes TestDriver fast. The cache makes the test run a maximum of 1.7x faster. It does not do the same AI vision analysis again. The agent thinks only when it sees something new.

// First run: builds cache
await testdriver.find('submit button');

// Second run: exact match
await testdriver.find('submit button');

Automatic Caching

TestDriver enables learning automatically. You do not need configuration. TestDriver computes the cache key from these. The cache key is the fingerprint that TestDriver uses to know what it learned:

• File hash: The SHA-256 hash of the test file contents
• Selector prompt: The exact text description that you give to find()
• Screenshot context: The perceptual hash of the present screen state
• Platform: The operating system and the browser version

When you change your test file, the hash changes automatically. This makes the old cache entries not valid. Then TestDriver does a new AI analysis with your new test logic.

import { test } from 'vitest';
import { chrome } from 'testdriverai/presets';

test('auto-cached test', async (context) => {
  const { testdriver } = await chrome(context, {
    url: 'https://example.com'
  });

  // First call: AI analyzes screen, saves to cache
  await testdriver.find('More information link'); // 2.1s

  // Second call: cache hit, instant response
  await testdriver.find('More information link'); // 12ms ⚡