How does the browser get into the right account?
Website authentication crosses several boundaries: the user who authorizes access, the system that holds credentials, the browser that submits them, and any model or code driving the page. Reusing a login and collecting a new identity are separate workflows.
For a customer-facing app, associate each stored connection with the correct application user before opening a browser. Reusing another user's profile can produce a technically successful run in the wrong account.
Compare the login path
Notte: Vaults substitute credential placeholders in supported browser actions outside the model context. Managed Auth checks requested saved connections before automation. Personas supply an inbox and optional phone number for verification workflows.
Kernel: Managed Auth handles website login and eligible connection recovery. Vault fill is a separate flow for applications that control navigation and form submission; the reviewed vault documentation labels that surface as preview.
Sources: docs.notte.cc [1] ↗kernel.sh [2] ↗
Compare saved state
Notte: Profiles save cookies, local storage and session storage. Sessions start with fresh state by default. Persisting a profile writes state back when the session ends; a running session can also save its state explicitly.
Kernel: Profiles preserve browser user-data-directory state, including cookies, site data, tabs and preferences. Profile sharing and save behavior need explicit treatment when parallel workers use seeded state.
Sources: docs.notte.cc [1] ↗kernel.sh [2] ↗
Compare the evidence from a run
Notte: Live view shows an active browser and can be embedded in an application. Recordings let you review a finished session. Function runs have their own history and results, so keep the run ID alongside the browser session ID.
Kernel: Live browser URLs support an embedded view and a read-only option. Replays and browser telemetry are separate observability surfaces; app invocation logs add execution context.
Sources: docs.notte.cc [1] ↗kernel.sh [2] ↗
How to evaluate this choice
Compare the concrete login path. A vault can fill a secret while your code controls the workflow; a managed connection may own more of the login process. Neither should be described as a universal guarantee that every website remains signed in.
- Identify whether the task uses an existing account or creates an approved new identity.
- Separate profile restoration from credential fill and connection readiness.
- Document which component can access credential values and which only handles references.
- Verify the expected tenant and account after login.
- Provide a human handoff when the website requires user interaction.
Requirements side by side
| Requirement | Notte | Kernel |
|---|---|---|
| Saved browser state | Documented | Documented |
| Credential handling | Documented | Vaults (preview) |
| Website sign-in | Documented | Documented |
Sources: docs.notte.cc [1] ↗docs.notte.cc [2] ↗docs.notte.cc [3] ↗docs.notte.cc [4] ↗docs.notte.cc [5] ↗docs.notte.cc [6] ↗kernel.sh [7] ↗kernel.sh [8] ↗kernel.sh [9] ↗kernel.sh [10] ↗kernel.sh [11] ↗kernel.sh [12] ↗
Which approach fits?
Choose Notte when your browser workflow needs saved logins, credential fill or scheduled Python code alongside the browser.
Notte tradeoff: A saved profile restores browser state; it does not prove that a website still considers the user signed in. Use Managed Auth when the workflow needs connection readiness before it starts.
Choose Kernel when your code makes many browser calls and you want to deploy it beside the browser, or you need Kernel's managed sign-in flow.
Kernel tradeoff: Browser-local code changes the deployment model. Check app action behavior, account limits and persistent-state ownership before moving an external worker into it.
Sources: docs.notte.cc [1] ↗kernel.sh [2] ↗
A useful acceptance check
Write a pass/fail result for the real task before running the evaluation. Record the account, configuration and code version next to that result. Repeat failures need an explanation, not an automatically different browser configuration.