Telegram Bot API: Mini Apps and Attachment Menu

Purpose

Use this skill when chat UI is not enough and the bot needs a full web interface inside Telegram.

Core API surface

• WebAppInfo
• web_app buttons
• menu-button Web App launch
• web_app_data
• answerWebAppQuery
• attachment-menu bot exposure

Developer guidance

1. Treat the Mini App as a separate frontend application with a secure backend.
2. Validate Telegram init data server-side.
3. Keep Bot API message delivery and Mini App state synchronized explicitly.
4. Use the bot chat for durable notifications and approvals; use the Mini App for rich interaction.

Launch surfaces

• private-chat keyboard button
• inline keyboard button
• menu button
• direct t.me or deep-link based entry
• attachment menu where available

Product-fit guidance

Mini Apps are best for:

• checkout flows
• dashboards
• games with rich controls
• multi-step forms
• map or catalog experiences
• AI tools that need more than plain chat

Common mistakes

• Trusting client-provided Web App data without signature validation.
• Mixing chat handler state with browser session state implicitly.
• Building web flows that fail when Telegram theme or viewport changes.
• Treating attachment-menu availability as universal.

Read next

• 15-web-login-and-deep-linking
• 11-payments-stars-and-broadcasting
• 19-security-privacy-and-identity