Crypto Price Monitor

Monitor cryptocurrency prices and trigger alerts when thresholds are hit. Supports BTC, ETH, SOL, and 100+ other coins via CoinGecko API. Configure price ceilings, floors, or percentage moves. Alerts delivered to console, files, or Telegram.

Crypto Price Alerts

Monitor cryptocurrency prices and get alerts when targets are hit. No API key required — uses CoinGecko's free API.

What It Does

• Checks current prices for BTC, ETH, SOL, and 100+ coins
• Compares against your configured thresholds
• Alerts when price crosses above/below targets
• Supports percentage moves (e.g., "alert if BTC drops 5% in 1 hour")
• Can run once or on a schedule (cron)

Quick Start

Check a Single Price

bash

# Direct API call (no auth needed)
curl "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin,ethereum,solana&vs_currencies=usd&include_24hr_change=true"

Check with More Detail

bash

curl "https://api.coingecko.com/api/v3/coins/bitcoin?localization=false&tickers=false&community_data=false&developer_data=false&sparkline=false"

Alert Configuration

Create a crypto-alerts.json file:

json

{
  "alerts": [
    {
      "coin": "bitcoin",
      "symbol": "btc",
      "condition": "below",
      "price": 85000,
      "message": "BTC dropped below $85K!"
    },
    {
      "coin": "bitcoin",
      "symbol": "btc",
      "condition": "above",
      "price": 100000,
      "message": "BTC crossed $100K! 🚀"
    },
    {
      "coin": "ethereum",
      "symbol": "eth",
      "condition": "below",
      "price": 3000,
      "message": "ETH below $3K"
    },
    {
      "coin": "solana",
      "symbol": "sol",
      "condition": "above",
      "price": 200,
      "message": "SOL above $200!"
    }
  ],
  "telegram_bot_token": "YOUR_BOT_TOKEN",
  "telegram_chat_id": "YOUR_CHAT_ID"
}

Python Alert Script

Save as crypto_alert.py:

python

#!/usr/bin/env python3
import requests
import json
import sys
import os
from datetime import datetime

COINGECKO_API = "https://api.coingecko.com/api/v3"

def get_price(coin_id):
    url = f"{COINGECKO_API}/simple/price"
    params = {
        "ids": coin_id,
        "vs_currencies": "usd",
        "include_24hr_change": "true",
        "include_last_updated_at": "true"
    }
    r = requests.get(url, params=params, timeout=10)
    r.raise_for_status()
    data = r.json()
    return data[coin_id]["usd"], data[coin_id].get("usd_24h_change", 0)

def check_alerts(alerts_config):
    triggered = []
    for alert in alerts_config.get("alerts", []):
        coin = alert["coin"]
        condition = alert["condition"]
        target = alert["price"]
        message = alert["message"]
        
        try:
            price, change_24h = get_price(coin)
        except Exception as e:
            print(f"Error fetching {coin}: {e}")
            continue
        
        should_fire = False
        if condition == "above" and price >= target:
            should_fire = True
        elif condition == "below" and price <= target:
            should_fire = True
        
        if should_fire:
            triggered.append({
                "coin": coin,
                "price": price,
                "target": target,
                "condition": condition,
                "message": message,
                "change_24h": change_24h,
                "time": datetime.now().isoformat()
            })
            print(f"🚨 ALERT: {message} (Current: ${price:,.2f})")
        else:
            print(f"  {coin.upper()}: ${price:,.2f} (24h: {change_24h:+.2f}%) — {condition} ${target:,.2f}: {'✓' if should_fire else 'not triggered'}")
    
    return triggered

def send_telegram(message, bot_token, chat_id):
    if not bot_token or not chat_id:
        return
    url = f"https://api.telegram.org/bot{bot_token}/sendMessage"
    payload = {"chat_id": chat_id, "text": message, "parse_mode": "HTML"}
    requests.post(url, json=payload, timeout=10)

if __name__ == "__main__":
    config_path = os.path.join(os.path.dirname(__file__), "crypto-alerts.json")
    
    if len(sys.argv) > 1:
        config_path = sys.argv[1]
    
    if os.path.exists(config_path):
        with open(config_path) as f:
            config = json.load(f)
    else:
        print("No crypto-alerts.json found. Using default BTC/ETH/SOL check.")
        config = {
            "alerts": [
                {"coin": "bitcoin", "symbol": "btc", "condition": "above", "price": 0},
                {"coin": "ethereum", "symbol": "eth", "condition": "above", "price": 0},
                {"coin": "solana", "symbol": "sol", "condition": "above", "price": 0}
            ]
        }
    
    triggered = check_alerts(config)
    
    if triggered:
        summary = "🚨 <b>Crypto Alert Triggered</b>\n\n"
        for t in triggered:
            summary += f"{t['message']}\n"
            summary += f"Price: ${t['price']:,.2f} | 24h: {t['change_24h']:+.2f}%\n\n"
        
        bot_token = config.get("telegram_bot_token")
        chat_id = config.get("telegram_chat_id")
        if bot_token and chat_id:
            send_telegram(summary, bot_token, chat_id)
        
        with open("/tmp/crypto_alerts_triggered.json", "a") as f:
            f.write(json.dumps({"triggered": triggered, "time": datetime.now().isoformat()}) + "\n")

Usage Examples

Run Once

bash

python3 crypto_alert.py

Run on Schedule (Cron)

bash

# Every 15 minutes
*/15 * * * * cd /path/to/skill && python3 crypto_alert.py >> /tmp/crypto_alerts.log 2>&1

# Every hour at minute 0
0 * * * * cd /path/to/skill && python3 crypto_alert.py >> /tmp/crypto_alerts.log 2>&1

Check Specific Coin

bash

# Bitcoin
curl "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin&vs_currencies=usd&include_24hr_change=true"

# Multiple coins
curl "https://api.coingecko.com/api/v3/simple/price?ids=bitcoin,ethereum,solana,cardano,polkadot,avalanche-2,chainlink&vs_currencies=usd&include_24hr_change=true"

Supported Coins (Common IDs)

Symbol	CoinGecko ID
BTC	bitcoin
ETH	ethereum
SOL	solana
ADA	cardano
DOT	polkadot
AVAX	avalanche-2
LINK	chainlink
XRP	ripple
DOGE	dogecoin
MATIC	polygon
ARB	arbitrum
OP	optimism

For full list: curl https://api.coingecko.com/api/v3/coins/list?per_page=250

Alert Conditions

• above — Fire when price >= target
• below — Fire when price <= target
• percent_up — Fire when 24h change > X% (add percent_threshold field)
• percent_down — Fire when 24h change < -X% (add percent_threshold field)

Rate Limits

CoinGecko free API:

• ~10-30 calls/minute
• 10,000-50,000 calls/month
• Use caching if checking frequently
• Add sleep(1.2) between calls to be safe

Requirements

• requests Python library (pip install requests)
• CoinGecko API (free, no key needed)
• Optional: Telegram bot for push notifications
• Optional: cron for scheduled monitoring

Tips

1. Don't spam checks — 15-minute intervals are fine for most use cases
2. Cache prices — Store last check to avoid redundant API calls
3. Multiple conditions — One coin can have multiple alerts (above AND below)
4. Logging — Always log to a file so you can review what fired

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Based on real crypto monitoring work. CoinGecko API is free but respectful usage is expected.