Overview
Extract information from the current screen using AI and return it as a string. Describe what you want in natural language, and the AI reads the screen and returns the matching value — text, numbers, labels, status messages, or any other on-screen content.
Unlike assert(), which returns a boolean verdict, extract() returns the actual value so you can store it, compare it, or feed it into later steps and framework assertions.
Syntax
const value = await testdriver.extract(description)
const value = await testdriver.extract({ description })
Parameters
Returns
Promise<string> — The information read from the screen. Returns the extracted value as text; parse or cast it yourself if you need a number or other type.
Examples
Basic Extraction
// Read text content
const title = await testdriver.extract('the page title');
const heading = await testdriver.extract('the main heading text');
// Read numbers and prices
const price = await testdriver.extract('the total price shown in the cart');
const count = await testdriver.extract('the number of items in the list');
// Read status and confirmation values
const status = await testdriver.extract('the order status');
const orderNumber = await testdriver.extract('the order confirmation number');
Using the Extracted Value
// Store and reuse across steps
const orderNumber = await testdriver.extract('the order confirmation number');
console.log('Order:', orderNumber);
// Combine with framework assertions
import { expect } from 'vitest';
const message = await testdriver.extract('the success message text');
expect(message).toContain('successfully');
// Cast to a number when you need to compare
const totalText = await testdriver.extract('the cart total as a number without currency symbol');
expect(Number(totalText)).toBeGreaterThan(0);
Best Practices
Precise descriptions produce cleaner values:
// ❌ Too vague — may return extra surrounding text
const price = await testdriver.extract('price');
// ✅ Specific — targets a single value
const price = await testdriver.extract('the total price in the order summary, digits only');
Steer the output by describing the desired shape in the prompt:
// Strip currency symbols
const total = await testdriver.extract('the order total as a number without the dollar sign');
// Isolate a single field
const email = await testdriver.extract('the email address shown in the profile header');
Use extract() when a boolean assert() isn't enough and you need the actual value to inspect:
const confirmation = await testdriver.extract('the confirmation number');
expect(confirmation).toMatch(/^ORD-\d{6}$/);
Use Cases
// Read the confirmation the app generated
const orderNumber = await testdriver.extract('the order confirmation number');
const eta = await testdriver.extract('the estimated delivery date');
console.log(`Order ${orderNumber} arrives ${eta}`);
```
const tooltipText = await testdriver.extract('the tooltip text');
expect(tooltipText).toContain('tax included');
```
const addBtn = await testdriver.find('add funds button');
await addBtn.click();
// Read it again after and compare
const after = await testdriver.extract('the account balance');
expect(Number(after.replace(/[^0-9.]/g, ''))).toBeGreaterThan(
Number(before.replace(/[^0-9.]/g, ''))
);
```
// ...and type it into the next
const codeField = await testdriver.find('reset code input');
await codeField.click();
await testdriver.type(resetCode);
```
Complete Example
import { beforeAll, afterAll, describe, it, expect } from 'vitest';
import TestDriver from 'testdriverai';
describe('Extraction', () => {
let testdriver;
beforeAll(async () => {
testdriver = new TestDriver(process.env.TD_API_KEY);
await testdriver.auth();
await testdriver.connect();
});
afterAll(async () => {
await testdriver.disconnect();
});
it('should capture the order confirmation', async () => {
await testdriver.focusApplication('Google Chrome');
// Complete a checkout
const checkoutBtn = await testdriver.find('checkout button');
await checkoutBtn.click();
const placeOrderBtn = await testdriver.find('place order button');
await placeOrderBtn.click();
// Verify we reached confirmation
await testdriver.assert('the order confirmation page is displayed');
// Extract the details the app generated
const orderNumber = await testdriver.extract('the order confirmation number');
const total = await testdriver.extract('the order total as a number without currency symbol');
// Assert on the extracted values
expect(orderNumber).toBeTruthy();
expect(Number(total)).toBeGreaterThan(0);
});
});
How It Works
- TestDriver captures a screenshot of the current screen
- The image and your description are sent to the TestDriver API
- The AI reads the requested information from the screenshot
- The extracted value is returned as a string