Slack Bot Notifications for CAPTCHA Events

When your CAPTCHA pipeline starts failing at scale, you need to know immediately — not hours later when scraping results are empty. This guide sets up Slack notifications for failures, low balance, and abnormal error rates.

Setup: Create a Slack webhook

Go to api.slack.com/apps → Create New App
Choose Incoming Webhooks → Activate
Click Add New Webhook to Workspace → Select a channel
Copy the webhook URL

Python: Slack notification helper

import requests
import json
from datetime import datetime

SLACK_WEBHOOK_URL = "https://hooks.slack.com/services/T00/B00/xxx"


def send_slack_alert(title, message, color="#ff0000", fields=None):
    """Send a formatted Slack alert."""
    attachment = {
        "color": color,
        "title": title,
        "text": message,
        "ts": int(datetime.now().timestamp()),
    }
    if fields:
        attachment["fields"] = [
            {"title": k, "value": str(v), "short": True}
            for k, v in fields.items()
        ]

    payload = {"attachments": [attachment]}
    resp = requests.post(SLACK_WEBHOOK_URL, json=payload, timeout=10)
    return resp.status_code == 200

Alert 1: Solve failure

def notify_solve_failure(task_id, captcha_type, error_code, site_url):
    send_slack_alert(
        title="CAPTCHA Solve Failed",
        message=f"Task `{task_id}` failed with `{error_code}`",
        color="#ff0000",
        fields={
            "Type": captcha_type,
            "Error": error_code,
            "Site": site_url,
            "Time": datetime.now().strftime("%H:%M:%S"),
        },
    )

# Use after a failed solve
result = poll_for_result(task_id)
if result.get("error"):
    notify_solve_failure(task_id, "recaptcha_v2", result["error"], "https://example.com")

Alert 2: Low balance

def check_balance_alert(api_key, threshold=5.0):
    """Alert when balance drops below threshold."""
    resp = requests.get("https://ocr.captchaai.com/res.php", params={
        "key": api_key, "action": "getbalance", "json": "1"
    }).json()

    balance = float(resp.get("request", 0))

    if balance < threshold:
        send_slack_alert(
            title="Low CaptchaAI Balance",
            message=f"Balance is ${balance:.2f} (threshold: ${threshold:.2f})",
            color="#ff9900",
            fields={
                "Current Balance": f"${balance:.2f}",
                "Threshold": f"${threshold:.2f}",
            },
        )
    return balance

# Run periodically
import threading

def balance_monitor(api_key, interval=300):
    """Check balance every 5 minutes."""
    check_balance_alert(api_key)
    timer = threading.Timer(interval, balance_monitor, args=[api_key, interval])
    timer.daemon = True
    timer.start()

balance_monitor("YOUR_API_KEY")

Alert 3: High error rate

from collections import deque

class ErrorRateNotifier:
    def __init__(self, window=50, threshold=0.3, cooldown=300):
        self.results = deque(maxlen=window)
        self.threshold = threshold
        self.cooldown = cooldown
        self.last_alert = 0

    def record(self, success):
        self.results.append(success)

        if len(self.results) < 20:
            return

        error_rate = 1 - sum(self.results) / len(self.results)

        import time
        now = time.time()
        if error_rate > self.threshold and (now - self.last_alert) > self.cooldown:
            self.last_alert = now
            send_slack_alert(
                title="High CAPTCHA Error Rate",
                message=f"Error rate: {error_rate:.0%} over last {len(self.results)} tasks",
                color="#ff0000",
                fields={
                    "Error Rate": f"{error_rate:.1%}",
                    "Window": f"{len(self.results)} tasks",
                    "Threshold": f"{self.threshold:.0%}",
                },
            )

notifier = ErrorRateNotifier()

# After each solve attempt
notifier.record(success=True)   # solved
notifier.record(success=False)  # failed

Node.js implementation

const axios = require('axios');

const SLACK_WEBHOOK = 'https://hooks.slack.com/services/T00/B00/xxx';

async function sendSlackAlert(title, message, color = '#ff0000', fields = {}) {
  const attachment = {
    color,
    title,
    text: message,
    ts: Math.floor(Date.now() / 1000),
    fields: Object.entries(fields).map(([k, v]) => ({
      title: k, value: String(v), short: true,
    })),
  };

  await axios.post(SLACK_WEBHOOK, { attachments: [attachment] });
}

// Failure alert
async function notifySolveFailure(taskId, type, error) {
  await sendSlackAlert(
    'CAPTCHA Solve Failed',
    `Task \`${taskId}\` failed: \`${error}\``,
    '#ff0000',
    { Type: type, Error: error }
  );
}

// Balance alert
async function checkBalance(apiKey, threshold = 5.0) {
  const resp = await axios.get('https://ocr.captchaai.com/res.php', {
    params: { key: apiKey, action: 'getbalance', json: 1 },
  });
  const balance = parseFloat(resp.data.request);

  if (balance < threshold) {
    await sendSlackAlert(
      'Low CaptchaAI Balance',
      `Balance: $${balance.toFixed(2)}`,
      '#ff9900',
      { Balance: `$${balance.toFixed(2)}`, Threshold: `$${threshold.toFixed(2)}` }
    );
  }
  return balance;
}

// Periodic check
setInterval(() => checkBalance('YOUR_API_KEY'), 5 * 60 * 1000);

Daily summary

def send_daily_summary(stats):
    """Send a daily digest to Slack."""
    send_slack_alert(
        title="Daily CAPTCHA Summary",
        message=f"{stats['total']} tasks processed",
        color="#36a64f",
        fields={
            "Solved": stats["solved"],
            "Failed": stats["failed"],
            "Avg Solve Time": f"{stats['avg_time_ms']}ms",
            "Total Cost": f"${stats['total_cost']:.2f}",
            "Success Rate": f"{stats['success_rate']:.1%}",
        },
    )

Troubleshooting

Problem	Cause	Fix
Webhook returns 403	Invalid webhook URL	Re-create the webhook in Slack
Too many alerts	No cooldown	Add cooldown period between alerts
Alerts delayed	Webhook timeout	Set timeout on requests (10s)
Channel not receiving	Wrong channel selected	Check webhook channel configuration