Build a Telegram Inline Bot People Can Call From Any Chat

What inline mode does

In any chat, a user types @yourbot and a search word in the message field. Your bot shows a list of results above the field, and the one they pick is sent straight into that chat. Your bot does not have to be a member of the chat. Inline mode suits "find it and paste it" jobs such as GIF search, translation or sharing links. For how this looks to users, see using inline bots without adding them.

Turn it on in @BotFather

1. Choose your bot and turn on inline mode with /setinline.
2. Set the placeholder, the grey hint shown in the message field, for example "Search GIFs…".
3. Optionally turn on /setinlinegeo to receive the user's location with each query, and /setinlinefeedback to learn which result they picked.

Receive a query and answer it

As the user types, your bot receives inline_query updates (see webhooks vs long polling). Each one has the search text in query and an id. Reply with answerInlineQuery using that ID:

curl https://api.telegram.org/bot123456:ABC-EXAMPLE/answerInlineQuery \
  -H "Content-Type: application/json" \
  -d '{"inline_query_id":"QUERY_ID",
       "results":[{"type":"article","id":"1","title":"Say hello",
         "input_message_content":{"message_text":"Hello there"}}],
       "cache_time":60}'

Answer inline queries fast

Users expect results while they are still typing. If your answer is slow, nothing appears. Prepare heavy searches in advance, set a sensible cache_time for common queries, and have default results ready for when the query is empty, that is, when the user has typed only @yourbot.

Other things worth knowing

• Which result was chosen: with feedback on, the picked result arrives as chosen_inline_result, useful for statistics.
• Starting from a button: an inline button with switch_inline_query lets the user pick a chat and opens inline mode there; see bot buttons.
• Groups can block it: a group's permissions can stop members from using inline bots, and then your results cannot be sent there.