Open-source Percy alternatives

Playwright is an open-source framework for testing and automating web applications. A single API drives Chromium, Firefox and WebKit, so the same script or test can cover all three engines. It is used for end-to-end testing, for scripted browser tasks and, increasingly, as a tool that AI agents call to operate a browser.

The bundled Playwright Test runner executes tests in parallel with a fresh browser context per test, which gives isolation without the cost of launching a new browser. Locators mirror how users see the page, actions wait automatically until elements are ready, and assertions retry until they pass. Failures can be investigated with traces that capture screenshots, DOM snapshots, network requests and console output in a Trace Viewer.

Beyond the test runner there is a standalone library for scripts, a CLI aimed at coding agents, an MCP server for LLM-driven automation and a VS Code extension. The code is Apache-2.0 licensed and runs on your own machines and CI servers, with no hosted service required.

Magnitude is a browser agent that uses vision AI so you can control a browser with natural language. It navigates by looking at the interface and planning actions, interacts with precise mouse and keyboard actions, extracts structured data, and verifies results with a built-in test runner that supports visual assertions.

Rather than drawing numbered boxes around page elements, which the authors say generalizes poorly on complex modern sites, it has a visually grounded model give pixel coordinates, making it independent of the page's DOM structure and extendable to desktop apps or virtual machines. It can be used to automate web tasks, integrate apps that have no APIs, extract data, test web apps or build other browser agents. The README reports a 94% score on the WebVoyager benchmark.

Magnitude needs a large visually grounded model; Claude Sonnet 4 is recommended and Qwen-2.5VL 72B is also compatible. A setup command creates a project with an example script, and the test runner adds a tests directory with a configuration file and example test. It is written in TypeScript and licensed under Apache-2.0.