@-mention a browser tab to have the agent work in it

[bilalbayram]

Problem

I open a page in T3's browser, sign in, and want the agent to continue from there. Right now the agent has to guess which tab I mean: it lists the thread's tabs and picks one, or opens a new tab that doesn't have my session. With several tabs open, I can't point it at the right one.

Codex lets you @ a browser tab for this.

Proposal

Type @ in the composer and see the thread's open browser tabs next to threads and files, each with its title and URL. Picking one adds a tab chip to the message.

The chip tells the agent "work in this tab". The prompt includes the tab's ID, title and URL, and the agent drives that exact tab with the browser tools it already has, which accept a tab ID. Nothing is copied or captured when you send the message; the agent reads the live page.

Details

• Control: mentioning a tab you're not using lets the agent act in it. If you're driving the tab, the agent waits or asks, as it does today.
• Closed or navigated tabs: the message keeps the original title and URL, so the agent can tell what you meant and reopen it.
• Providers without T3's browser tools still get the title and URL as context.
• Clients: web, desktop and mobile all have browser tabs, so the @ menu should list them on all three.
• Environments: list only tabs from the current thread's environment, so the agent can always reach the tab it's given.

Related

• fix(preview): agent browser tabs show one page and work while hidden #22877: makes sure the agent and the Browser panel see the same page. Handing over a signed-in tab needs that fix.
• [Feature]: @ mentions for threads and projects as pointers the agent reads through t3-code tools #14086: @-mentions for threads and projects, the same pointer idea for threads and projects.