Cookie Sync

At a glance

Cookie Sync copies local Chrome cookies into a persistent Browserbase context so a cloud browser can reuse an existing login. It is worth considering when repeated authentication blocks an authorised workflow. The convenience comes from moving login credentials into the cloud; the script’s default includes every cookie unless you supply a domain filter.

Good fit

Developers who already use Browserbase and can explicitly authorise a limited test identity for a particular site. Reusing the context can avoid repeating login screens. For testing around a local coding workflow, Expect instead integrates a browser with the coding agent; it is a different operating arrangement.

Consider something else when

Credentials must remain on the device, or the target site requires state that cookies alone cannot reproduce. A domain filter includes subdomains, and the script reads the local cookie set before filtering what it sends. Copying a login also does not guarantee that the receiving site will accept it.

Start here

Read the skill and script before installing. Use Node 22+, a debuggable Chromium profile containing only an authorised test login, and your Browserbase account. Supply --domains for that site, verify the signed-in page in the returned context, then release the browser session. No cookies or credentials were exported during this source review.

Cost and requirements

The skill is MIT-licensed; the cloud browser is a separate service requiring a Browserbase API key. Current pricing advertises one browser hour and a 15-minute session limit on Free, or Developer at $20 monthly with included usage and overages. Optional proxies and other platform features have their own limits and charges.

Limits to know

Closing the browser session does not delete its saved context. Official documentation says contexts persist until explicitly deleted or invalidated, while websites can separately expire or revoke their cookies. The review read the sync script and context documentation; it did not test authentication, remote-debugging setup, session persistence or deletion.

Related work

• Browserbase: the cloud browser service required by Cookie Sync (complement)
• Expect: browser testing within a coding-agent workflow (context)

Still unclear

• Does the specific target site accept copied cookies, or require additional storage, device state or a fresh login?