webkit-remote-inspector-client.js

var host = "localhost:9999"
var page = 1

var ws = new WebSocket("ws://" + host + "/devtools/page/" + page)
ws.onmessage = function(m) {console.log(m.data)}

var counter = 0
var send = function (method, params) {
  ws.send(JSON.stringify({id: counter++, 'method': method, 'params': params}))
}

ws.onopen = function() {
  send('Runtime.evaluate', {expression: 'alert("hello from remote debugger")'})
  send('Runtime.evaluate', {expression: '5+5'})
}

webkit-remote-inspector-client.py

import json
import socket

from websocket import WebSocket
ws = WebSocket()

# if ipv6
ws.io_sock = ws.sock = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
ws.connect("ws://localhost:9999/devtools/page/1")

counter = 0

def send(method, params):
  global counter
  counter += 1
  # separators is important, you'll get "Message should be in JSON format." otherwise
  message = json.dumps({"id": counter, "method": method, "params": params}, separators=(',', ':'))
  print "> %s" % (message,)
  ws.send(message)

def recv():
  result = ws.recv()
  print "< %s" % (result,)

send('Runtime.evaluate', {'expression': 'alert("hello from python")'})
recv()