nekoro-browser

Imported from zeshuochen/nekoro-browser (AGENTS.md). Install upstream with npx skills add zeshuochen/nekoro-browser. Copyright stays with the author.

nekoro-browser is a CLI that lets an agent drive the user's daily Chrome via a MV3 extension (chrome.debugger API) + a local daemon, keeping the real login state — no --remote-debugging-port (Chrome 136+ blocks that on the default profile anyway).

Code priorities

• Clarity
• Precision
• Low verbosity
• Never fabricate success — helpers return {"ok": false, "error": ...} on failure, not a silently-wrong {"ok": true}

Overview

Two halves, one wire (HTTP + WebSocket, same port):

• extension/ — MV3 extension. background.js is the service worker: WS transport to the daemon, chrome.debugger attach/CDP dispatch, dialog auto-handling, tab lifecycle. keepalive.js is a content script that gives the service worker an independent wake vector (MV3 workers get evicted; a plain WS/alarm keep-alive alone isn't reliable).
• src/nekoro_browser/ — the daemon + CLI.
  • daemon.py — long-lived middleman process between the extension and the agent's -c code
  • bridge.py — the WS/HTTP transport
  • lifecycle.py — pid file, process fingerprint, stale-daemon self-heal
  • helpers.py — CDP wrapper functions auto-imported into -c scripts, each a thin (≤10 line) wrapper over one CDP capability
  • cli.py — the nekoro-browser command
  • mcp_server.py — the nekoro-browser-mcp command: stdio JSON-RPC MCP server for clients that don't read skill files (Claude Desktop, Cursor, opencode, Codex, VS Code/Copilot, …). Tools are reflected off helpers.py via inspect.signature, then forwarded to the same daemon /exec endpoint the CLI uses — no second execution path to keep in sync.

SKILL.md tells agents how to use the CLI and lists every helper. README.md covers install + quick start for humans.

An agent operating nekoro-browser edits two places:

• src/nekoro_browser/agent_helpers.py — task-specific browser helpers the agent adds at runtime; hot-reloaded via reload_agent_helpers(), no daemon restart needed
• domain-skills/ — Markdown notes on specific sites, written and read by the agent. Empty by default and never imported; workflows go in agent_helpers.py.

Testing

tests/test_*.py are stdlib-style, not pytest: assert + a final print("ALL OK"), run via uv run python tests/test_X.py. Extension JS has no unit-test surface — verify syntax with node --check, behavior needs a live Chrome.

tests/browser_regression.py runs the packaged wheel and a PyPI-to-wheel upgrade in real Chrome for Testing with isolated profiles. Its test-only CDP pipe bridge uses Node's standard library. See README for invocation; CI gates publishing on this test.

Contributing

Consider what is really needed. Prefer the smallest diff that fixes the bug. Don't add speculative config/flags for scenarios that aren't happening yet.