When to Use This Skill

Use the Kernel Python SDK when you need to:

• Build browser automation scripts - Create Python programs that control remote browsers

• Execute server-side automation - Run Playwright code directly in the browser VM without local dependencies

• Manage browser sessions programmatically - Create, configure, and control browsers from code

• Build scalable scraping/testing tools - Use browser pools and profiles for high-volume automation

• Deploy automation as actions - Package scripts as Kernel actions for invocation via API

When NOT to use:

• For CLI commands (e.g., kernel browsers create ), use the kernel-cli skill instead

• For quick one-off tasks, the CLI may be simpler than writing code

Core Concepts

SDK Architecture

The SDK is organized into resource-based modules:

• kernel.browsers

• Browser session management (create, list, delete)

• kernel.browsers.playwright

• Server-side Playwright execution

• kernel.browsers.computer

• OS-level controls (mouse, keyboard, screenshots)

• kernel.browser_pools

• Pre-warmed browser pool management

• kernel.profiles

• Persistent browser profiles (auth state)

• kernel.auth.connections

• Managed auth (create, login, submit, follow, retrieve, delete)

• kernel.credential_providers

• External credential providers (1Password)

• kernel.proxies

• Proxy configuration

• kernel.extensions

• Chrome extension management

• kernel.deployments

• App deployment

• kernel.invocations

• Action invocation

Two Automation Approaches

1. Server-side Execution (RECOMMENDED)

• Execute Playwright code directly in browser VM using kernel.browsers.playwright.execute(session_id, code="...")

• session_id must be passed as a positional argument (first parameter), not as id= keyword

• Response accessed via response.result

• MUST use return in code to get data back

• Best for: Most use cases, production automation, parallel execution, actions

2. CDP Connection (Client-side)

• Connect Playwright to browser via CDP WebSocket URL

• Code runs locally, browser runs remotely; requires local Playwright installation

• Best for: Complex debugging, specific local development needs

Patterns Reference

Import Patterns

• Standard: from kernel import Kernel

• For actions: import kernel and from kernel import Kernel

• For typed payloads: from typing import TypedDict

• For CDP: from playwright.async_api import async_playwright

SDK Initialization

• client = Kernel() reads KERNEL_API_KEY from environment automatically

Action Handler Pattern

from typing import TypedDict from kernel import Kernel

app = kernel.App("app-name")

class TaskInput(TypedDict): task: str

@app.action("action-name") async def my_action(ctx: kernel.KernelContext, input_data: TaskInput): # Access input: input_data["task"] or input_data.get("task") ...

CDP Connection Pattern (Client-side)

async with async_playwright() as playwright: browser = await playwright.chromium.connect_over_cdp(kernel_browser.cdp_ws_url) context = browser.contexts[0] if browser.contexts else await browser.new_context() page = context.pages[0] if context.pages else await context.new_page()

Binary Data Handling

Binary data (screenshots, PDFs) returns as Node.js Buffer: {'data': [byte_array], 'type': 'Buffer'}

Follow canonical pattern above, then:

if response.success and response.result: data = bytes(response.result['data']) with open("output.png", "wb") as f: f.write(data)

Installation

• uv pip install kernel or pip install kernel

• For CDP: uv pip install playwright

References

• Kernel Documentation: https://www.kernel.sh/docs

• API Reference: https://www.kernel.sh/docs/api-reference/

• Templates: https://www.kernel.sh/docs/reference/cli/create#available-templates

• Quickstart Guide: https://www.kernel.sh/docs/quickstart

• Examples: examples