webdriver-bidi

Description

webdriveri-bidi provides a remote control API for browsers. It extends classic WebDriver by providing bidirectional communication between the browser and the client, allowing richer APIs that match the evented nature of the browser.

webdriver-bidi itself represents a fundamental tool for Interop. Modern web app testing tools such as Puppeteer and Playwright depend on a bidirectional API; Puppeteer already ships with full BiDi support, and Playwright has a work-in-progress implementation which today achieves a ~90% test pass rate in BiDi-supporting browsers. These tools are essential in enabling developers to create sites that work reliably across multiple browser engines.

With the rise of agentic browsing we are also seeing more end-user use cases for browser remote control, as well as more custom automation clients being written for specific use cases such as MCPs. That makes this a critical time to provide an interoperable cross-browser automation solution that meets modern requirements, and ensure that these developments don't entrench current browser-specific protocols, and reduce end user choice.

In terms of scope, our initial proposal would be to take the scope of the webdriver-bidi web-feature, which we believe represents a minimal baseline level of support: https://github.com/web-platform-dx/web-features/blob/main/features/webdriver-bidi.yml However we are happy to consider scope changes in either direction.

Specification

https://w3c.github.io/webdriver-bidi/

web-feature

webdriver-bidi

Test Links

• https://wpt.fyi/results/webdriver/tests/bidi?label=master&label=experimental&aligned (a subset corresponding to the agreed scope)

Additional Signals

No response

Start by reading the WebDriver BiDi specification and the linked web-feature proposal, then inspect the referenced Web Platform Tests results for the agreed-scope subset. Done requires an agreed scope and a defined implementation plan for the Interop project; the issue does not name repository files or a specific test to change.