Telegram bot

Call the official Telegram Bot API with curl + jq. The bot token is injected as $TELEGRAMBOT_BOT_TOKEN; an optional default target chat is $TELEGRAMBOT_CHAT_ID (e.g. @your_channel or a numeric id). Base URL: https://api.telegram.org/bot$TELEGRAMBOT_BOT_TOKEN/<METHOD>.

Every response is JSON {"ok":true,"result":...} on success, or {"ok":false,"error_code":<n>,"description":"<msg>"} on failure — always check .ok and show description verbatim. Common failures: 401 Unauthorized = bad/ revoked token (reconnect the connector), 400 Bad Request: chat not found = wrong chat_id, 403 Forbidden: bot is not a member of the channel chat / ... need administrator rights = add the bot to the channel as an admin with post rights, 429 with parameters.retry_after = rate-limited, wait that many seconds.

chat_id is @channelusername (public) or the numeric id (private channels/ groups, often negative like -1001234567890). Resolve/verify it with getChat.

Step 1 — verify the bot + target

BOT="https://api.telegram.org/bot$TELEGRAMBOT_BOT_TOKEN"
curl -sS "$BOT/getMe" | jq '{ok, bot: .result.username, name: .result.first_name}'
# confirm the bot can post to the target chat (must be admin in the channel):
CHAT="${TELEGRAMBOT_CHAT_ID:-@your_channel}"
curl -sS -G "$BOT/getChat" --data-urlencode "chat_id=$CHAT" \
  | jq '{ok, type: .result.type, title: .result.title, error: .description}'

Send a text post

Confirm the text and target chat with the user before posting publicly. Text is 1-4096 chars. Use parse_mode=HTML (simplest) or MarkdownV2.

CHAT="${TELEGRAMBOT_CHAT_ID:-@your_channel}"
curl -sS -G "$BOT/sendMessage" \
  --data-urlencode "chat_id=$CHAT" \
  --data-urlencode "text=<b>Hello</b> from the bot 👋  #ai" \
  --data-urlencode "parse_mode=HTML" \
  --data-urlencode "disable_web_page_preview=false" \
  | jq '{ok, message_id: .result.message_id, error: .description}'

The public post URL for a channel is https://t.me/<channelusername>/<message_id>.

• HTML mode supports <b> <i> <u> <s> <a href> <code> <pre> <blockquote>. Escape literal < > & as < > &.
• MarkdownV2 requires escaping _ * [ ] ( ) ~ \ > # + - = | { } . !with`.
• Always send text via --data-urlencode so newlines/Cyrillic/emoji aren't mangled.

Send a photo with caption

CHAT="${TELEGRAMBOT_CHAT_ID:-@your_channel}"
curl -sS -G "$BOT/sendPhoto" \
  --data-urlencode "chat_id=$CHAT" \
  --data-urlencode "photo=https://cdn.example.com/pic.jpg" \
  --data-urlencode "caption=<b>Caption</b> text" \
  --data-urlencode "parse_mode=HTML" \
  | jq '{ok, message_id: .result.message_id, error: .description}'

photo accepts an HTTPS URL (≤5 MB, Telegram fetches it), a Telegram file_id, or an uploaded file. Caption is 0-1024 chars. For an album use sendMediaGroup.

Edit / delete a message

# edit text (same chat_id + message_id)
curl -sS -G "$BOT/editMessageText" \
  --data-urlencode "chat_id=$CHAT" --data-urlencode "message_id=123" \
  --data-urlencode "text=Updated text" --data-urlencode "parse_mode=HTML" \
  | jq '{ok, error: .description}'

# delete a message
curl -sS -G "$BOT/deleteMessage" \
  --data-urlencode "chat_id=$CHAT" --data-urlencode "message_id=123" \
  | jq '{ok, error: .description}'

deleteMessage works for the bot's own channel posts within 48 hours (and needs can_delete_messages/post rights).

Gotchas

• The bot must be added to the channel/group as an admin with post rights, or sends return 403. getChat first to confirm access.
• Channel numeric ids are large negative numbers (-100...); prefer @username for public channels.
• Free broadcast limit is ~30 msg/s; space out bulk sends or you'll hit 429 (respect parameters.retry_after).
• This is the bot speaking (not your personal account) — for reading your own DMs / groups as yourself, use the telegram (MTProto) connector instead.