Telegram Bot

Overview

The Telegram Bot API lets you build bots that send and receive messages, photos, documents, polls, and more inside Telegram — with zero hosting cost for the API itself. Bots are controlled over plain HTTPS calls; Telegram pushes updates to you either via long polling or webhooks.

Getting Started

1. Talk to @BotFather in Telegram and run /newbot.
2. Copy the bot token — it looks like 123456789:AAHf....
3. Verify it works (this is what an invalid token returns — HTTP 401):

curl "https://api.telegram.org/bot123456789:AAHf.../getMe"

4. Send your first message:

curl -X POST "https://api.telegram.org/botTOKEN/sendMessage" \
  -d chat_id=123456789 -d text="Hello from my bot!"

How updates arrive

Authentication

• The token IS the authentication — it’s embedded in the URL path (/bot<TOKEN>/method), not in a header.
• Keep it secret: anyone with the token controls your bot. Use environment variables, never commit it.
• getMe is the standard token health-check.

Rate Limits & Notes

• No hard rate limit is documented, but Telegram expects bots to respect humans: don’t spam the same chat.
• The API does not set CORS headers — call it from a server, not from browser JavaScript.
• sendPhoto/sendDocument accept file IDs, URLs, or multipart/form-data uploads.
• For heavy traffic, use webhooks + max_connections instead of polling.

FAQ

Is the Telegram Bot API free? Yes — creating bots and calling the API is free.

Do I need a server for my bot? Only for webhook mode. Long-polling (getUpdates) works from any process that can make HTTPS calls.

Can I call it from the browser? Not directly — the API doesn’t send CORS headers and the token would be exposed. Always call from your backend.