Browsers for agents
Agents often need the web: a dashboard to read, a form to fill, a page to check after a deploy. SpecWithCode gives them two ways in, and you can watch and take over in both.
| In-app browser | SpecWithCode Browser extension | |
|---|---|---|
| Where it runs | Inside SpecWithCode, beside the thread | In your own Chrome profile |
| Signed in as | An in-app profile: imported cookies or a fresh login | You, with that Chrome profile's logins |
| Agents of | Every provider | Every provider |
| Turn it on | Settings > Integrations > Agent browser access, for every project, with a per-project override | Settings > Chrome, per machine |
Watch it
A real Codex worker in SpecWithCode 1.0.47 opens a sample app in the in-app browser beside its thread and fills in a form; then you take over, type, hand back, and the agent's screenshot lands in the chat.
The in-app browser
Every thread has a browser beside it that you and the agent share: you watch and steer, the agent clicks and types. It has tabs, an address bar, DevTools, screenshots and screen recordings, element picking to send part of a page to the chat, a device toolbar for fixed viewports, and a list of the web servers running on the machine.
With agent browser access on, agents get the preview_* tools from SpecWithCode's MCP server (preview_open, preview_navigate, preview_snapshot, preview_click, preview_type and more). The tab an agent opens shows up beside its thread.
One profile per account
Each browser profile keeps its own cookies and storage. Agent tabs use isolated storage unless you pick a profile for them.
- Settings > Integrations > Browser profiles > Import from, then pick a browser and its profile, for example Chrome, "Work". Only cookies are copied, never saved passwords.
- In the new profile's menu, choose Use for agents.
- Repeat for each account, one in-app profile per account, so two logins to the same service never mix.
Cookie import works for Chrome, Edge, Brave, Vivaldi, Opera, Arc, Helium, Firefox and Safari on macOS.
The SpecWithCode Browser extension
The extension lets agents use one of your real Chrome profiles: your tabs, your logins, on this computer only. Agents of every provider can use it. It is the way SpecWithCode recommends for agents to work in Chrome.
- Open Settings > Chrome and pick the machine; each machine has its own Chrome.
- Install SpecWithCode Browser from the Chrome Web Store in the Chrome profile agents should use: choose Add to Chrome in SpecWithCode, or open the link in that profile, then Add extension. Chrome keeps it up to date.
- Choose Show pairing code and copy it.
- Click the SpecWithCode icon in Chrome's toolbar, paste the code, name the profile (for example Work or Marketing) and click Pair.
From then on:
- Every tab an agent opens or works in sits in a visible "SpecWithCode" tab group with the profile's name.
- Drag a tab out of the group and it is yours again; the agent lets go of it.
- Pause in the extension stops all agent access at once. Unpair forgets the pairing.
- Chrome's own pages (
chrome://, extension pages, DevTools) cannot be controlled.
The extension talks only to SpecWithCode on the same computer, over a loopback connection. A pairing code that points anywhere else is refused, so a pasted code cannot connect your browser to another machine. It has no server of its own, no analytics and no remote code. Details: SpecWithCode Browser privacy policy.
Why agents cannot drive your default Chrome profile directly
Since Chrome 136, Chrome refuses remote debugging on its default user-data folder, where your everyday profiles live, because malware used it to steal cookies. SpecWithCode does not work around that protection. Use the extension for a real profile, or import its cookies into an in-app profile.
For websites only; to work in native apps on the Mac, agents use computer use.