Where does the browser automation code run?
An external worker, a hosted browser Function, a browser-local app action and a hosted agent are different execution models. The choice determines who deploys the code, starts the browser, records the result and stops the run.
A scheduled job should return a verified result and stop its owned browser even when an action fails. The scheduler's successful HTTP trigger is not proof that the browser completed the business operation.
Compare the execution model
Kernel: Deploy a TypeScript or Python App and expose Actions that callers invoke. Kernel co-locates code with the browser environments the app creates. An Action invocation is the execution unit rather than a bare CDP connection.
Browserless: Browserless supports several code and control surfaces. Compare the exact runtime endpoint or external runner you intend to use, including its language, deployment, versioning and invocation contract.
Compare deployment ownership
Kernel: Kernel Apps move the automation process next to the browser. Alternatively, an external process can control a browser through the browser API. Choose based on execution locality and deployment ownership.
Browserless: Browserless has cloud and self-hosted deployment paths. Managed dedicated deployments expose some account APIs that a fully self-hosted installation does not, so document the actual deployment rather than a generic feature list.
Compare the evidence from a run
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.
Browserless: BAP live URLs stream an active session and support human interaction. Browserless also documents video recording and session replay. Availability and connection parameters depend on the selected product.
How to evaluate this choice
Keep an external runner when you already operate one and need portability. A native execution layer can remove deployment work; browser-local code can reduce repeated network calls. Compare actual workload behavior before assuming either always wins.
- Confirm the supported language, entry point and dependency packaging.
- Trace deployment, version selection, invocation and cancellation.
- Keep the handler runtime limit separate from browser session duration.
- Decide whether scheduling is native or supplied by another service.
- Associate results and logs with both the code version and browser session.
Requirements side by side
| Requirement | Kernel | Browserless |
|---|---|---|
| Code execution | TypeScript / Python Apps | Product-dependent execution |
| Scheduled execution | App invocation path | External scheduler |
| Recordings / replay | Documented | Product-dependent |
Sources: kernel.sh [1] ↗kernel.sh [2] ↗kernel.sh [3] ↗kernel.sh [4] ↗kernel.sh [5] ↗kernel.sh [6] ↗docs.browserless.io [7] ↗docs.browserless.io [8] ↗docs.browserless.io [9] ↗docs.browserless.io [10] ↗docs.browserless.io [11] ↗docs.browserless.io [12] ↗
Which approach fits?
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.
Choose Browserless when you need a browser service that fits existing automation libraries or a self-hosted deployment, and can select the appropriate Browserless product.
Browserless tradeoff: The connection route and product matter. A feature documented for BAP or a managed dedicated deployment should not be assumed to exist on every shared BaaS endpoint.
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.
When Notte belongs on this shortlist
Kernel's browser-local Apps make execution placement part of the decision. Compare the repeated action path with the proposed Notte controller or Function deployment before concluding that a lifecycle or hourly-rate difference decides the workflow.
Choose the Browserless product and deployment before drawing a conclusion from its documentation. BAP, shared browser access and a self-hosted service can have different features; Notte's session and Function resources should be compared with the specific path you would purchase.
Notte: Functions deploy Python code with a run() entry point. Invoke them over HTTP or with an SDK, inspect run history, and roll back code by redeploying an earlier version as the latest version.
Consider this third option when its documented mechanism addresses a requirement left open by the two providers above. A working configuration on either original provider can still be the better choice; compare the task and ownership cost before switching.
Sources: kernel.sh [1] ↗docs.browserless.io [2] ↗docs.notte.cc [3] ↗