pip install python-telegram-bot anthropic

import os
import anthropic
from telegram import Update
from telegram.ext import Application, CommandHandler, MessageHandler, filters, ContextTypes

TELEGRAM_TOKEN = os.environ["TELEGRAM_BOT_TOKEN"]
claude = anthropic.Anthropic()

async def start(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None:
 await update.message.reply_text("Hi! I'm an AI assistant. Send me a message!")

def main() -> None:
 app = Application.builder().token(TELEGRAM_TOKEN).build()
 app.add_handler(CommandHandler("start", start))
 app.run_polling()

if __name__ == "__main__":
 main()

MAX_HISTORY = 20

def get_history(context):
 return context.chat_data.setdefault("history", [])

async def chat(update: Update, context: ContextTypes.DEFAULT_TYPE):
 history = get_history(context)
 history.append({"role": "user", "content": update.message.text})
 if len(history) > MAX_HISTORY:
 del history[:len(history) - MAX_HISTORY]

 response = claude.messages.create(
 model="claude-sonnet-4-6",
 max_tokens=1024,
 system="You are a helpful AI assistant in Telegram. Be concise.",
 messages=history,
 )
 answer = response.content[0].text
 history.append({"role": "assistant", "content": answer})
 await update.message.reply_text(answer)

async def summarize(update: Update, context: ContextTypes.DEFAULT_TYPE):
 if not context.args:
 await update.message.reply_text("Usage: /summarize <text>")
 return
 text = "".join(context.args)
 resp = claude.messages.create(
 model="claude-sonnet-4-6",
 max_tokens=512,
 messages=[{"role": "user", "content": f"Summarize in 3 bullet points:\n{text}"}],
 )
 await update.message.reply_text(resp.content[0].text)

from telegram import InlineKeyboardButton, InlineKeyboardMarkup
from telegram.ext import CallbackQueryHandler

async def mode(update: Update, context: ContextTypes.DEFAULT_TYPE):
 keyboard = [[
 InlineKeyboardButton("Concise", callback_data="mode_concise"),
 InlineKeyboardButton("Detailed", callback_data="mode_detailed"),
 ]]
 await update.message.reply_text("Choose mode:", reply_markup=InlineKeyboardMarkup(keyboard))

async def mode_callback(update: Update, context: ContextTypes.DEFAULT_TYPE):
 query = update.callback_query
 await query.answer()
 context.chat_data["mode"] = query.data.replace("mode_", "")
 await query.edit_message_text(f"Mode set: {context.chat_data['mode']}")

# /etc/systemd/system/telegram-ai-bot.service
[Unit]
Description=Telegram AI Bot
After=network.target

[Service]
User=ubuntu
WorkingDirectory=/home/ubuntu/telegram-bot
ExecStart=/home/ubuntu/telegram-bot/venv/bin/python bot.py
Environment=TELEGRAM_BOT_TOKEN=7123...
Environment=ANTHROPIC_API_KEY=sk-ant-...
Restart=always

[Install]
WantedBy=multi-user.target

sudo systemctl enable --now telegram-ai-bot