Write less. Test more.
Works with Playwright, WebDriver, Puppeteer, and Appium.
| Humans | Agents | |
|---|---|---|
| Less code written | Less tokens consumed | |
| CodeceptJS reads as actions, not selectors. Where Playwright and WebDriver make you wrangle locators by hand, you describe what the user does — the framework resolves the locator and dispatches it through Playwright, WebDriver, or Puppeteer. | ||
| Tests explain themselves | Agents understand intent faster | |
| You write automation the way you'd write a test case: what the user does, what they should see. No tangled selector chains polluting the file. A teammate scanning the scenario — or an agent picking it up — grasps the intent in seconds and can adjust it without reverse-engineering anything. | ||
| Declarative actions | Fewer failed tries, faster feedback | |
I.selectOption handles native <select>, custom comboboxes, and ARIA listboxes the same way. I.fillField works on plain inputs and rich editors alike. CodeceptJS adapts to whatever your page actually uses — fewer flaky retries for humans, fewer HTML dumps and tool calls for agents. | ||
Debug live with pause() | Debug live via MCP | |
| Drop pause() anywhere in a scenario and you land in an interactive REPL with the page state still warm — try commands, inspect elements, patch the test in place. Agents get the same surface through MCP: they drive the running test, pause on any step, poke at the page, then update the code and rerun in debug mode. | ||
| Opinionated by default | Universal skill set | |
| Page objects, data fixtures, mobile and web plugins — the framework ships with strong defaults instead of leaving you to assemble them. Agents inherit the same structure through the official skill set: they know how to write, debug, refactor, and organize tests the way the framework expects. | ||
Architecture and test design applied by default
Feature('Milestones');
Before(({ login }) => { login();});
Scenario('Create a milestone @smoke', ({ milestonePage }) => { milestonePage.open(); milestonePage.create({ name: 'Q2 Release', dueDate: '2024-06-30' }); milestonePage.checkVisible('Q2 Release');});
Scenario('Milestone tracks task progress', ({ I, milestonePage }) => { milestonePage.open(); milestonePage.select('Q2 Release'); I.see('0 / 5 tasks', '.progress'); I.see('0%', '.progress-bar');});
Scenario('Complete a milestone', ({ I, milestonePage }) => { milestonePage.open(); milestonePage.select('Q2 Release'); I.click('Mark as Complete'); I.see('Completed', '.milestone-status');});I.click('Login') finds the button — by text, by label, by ARIA role, by CSS — and clicks it. You describe the action. The framework picks the strategy. The test reads like the spec it came from.I.click or I.tap(), I.see, I.swipeLeft you use on the web. Mobile testing works on same princinples.I.have('user', { role: 'admin' }) this creates one, and removes after a test.We also created Explorbot — the world's first open-source self-testing agent. It explores your site, writes tests as it goes, and runs autonomously for hours on CI. Already have a regression suite? Explorbot finds the paths it never touched. Explorbot is powered by CodeceptJS and writes its tests.
“Test an application like Percona Monitoring and Management with so many dashboards & metric plots.”
“CodeceptJS helps us write tests which are good to read and easy to write, run on several browsers.”
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