🤖 Telegram Messaging Agent for Text/Audio/Images

Receive Telegram text/voice/image messages via n8n workflow, classify or analyze with AI, and auto-reply

Who

Builders with an n8n instance, Telegram Bot, and OpenAI API credentials

You get

Bot auto-detects message type (text/voice/image), runs AI classification or content analysis, and returns results to the user

You need

n8n · telegram

Steps

1. Configure Telegram Webhook

   Configure the Telegram Bot Webhook address in n8n so the bot can receive messages in real time. Set up both test and production endpoints, then verify the Webhook status.

   Setup guidance · Source text。n8n workflow Sticky Note1 node content; guides Webhook configuration

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   # How to set up a Telegram Bot WebHook
   
   ## WebHook Setup Process
   
   **Basic Concept**
   A WebHook allows your Telegram bot to automatically receive updates instead of manually polling the Bot API.
   
   **Setup Method**
   To set a WebHook, make a GET request using this URL format:
   ```
   https://api.telegram.org/bot{my_bot_token}/setWebhook?url={url_to_send_updates_to}
   ```
   Where:
   - `my_bot_token`: Your bot token from BotFather
   - `url_to_send_updates_to`: Your HTTPS endpoint that handles bot updates
   
   
   **Verification**
   To verify the WebHook setup, use:
   ```
   https://api.telegram.org/bot{my_bot_token}/getWebhookInfo
   ```
   
   A successful response looks like:
   ```json
   {
    "ok": true,
    "result": {
      "url": "https://www.example.com/my-telegram-bot/",
      "has_custom_certificate": false,
      "pending_update_count": 0,
      "max_connections": 40
    }
   }
   ```
   
   
   This method provides a simple and efficient way to handle Telegram bot updates automatically through webhooks rather than manual polling.

2. Receive message and validate user

   Receive Telegram messages via the Webhook node, then use a Set node to define allowed user info (first name, last name, user ID), and an IF node to match the sender. Users who fail validation receive an error message.

3. Route message type

   Use a Switch node to auto-route by message content: voice field → audio branch, text field → text branch, photo field → image branch, everything else → error handling.

4. Process text messages

   Extract message text, then use a Text Classifier node (connected to GPT-4o-mini) to judge whether the message is about creating a task/todo. If classified as task, reply with 'Task message: <content>'; otherwise reply with 'Other message: <content>'.

   Execution prompt · Source text。Text Classifier node categories[0].description

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   If the message is about about creating a task/todo

   Execution prompt · Source text。Text Classifier node categories[1].description

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   If the message is not about creating a task/todo

5. Process voice messages

   Download the voice file from Telegram, use the OpenAI node's audio/transcribe feature to convert speech to text. Then route through Text Classifier Audio (connected to GPT-4o-mini) as task or other, and send the corresponding formatted reply.

   Execution prompt · Source text。Text Classifier Audio node categories[0].description

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   If the message is about about creating a task/todo

   Execution prompt · Source text。Text Classifier Audio node categories[1].description

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   If the message is not about creating a task/todo

6. Process image messages

   Extract image file_id and caption, download the image from Telegram, convert to base64, then use the OpenAI node's image/analyze feature (model GPT-4O-MINI) to analyze the image content, and finally return the analysis result to the user.

Please build this Telegram multimodal messaging agent using the following n8n template. First confirm you have: 1) a publicly accessible n8n instance; 2) a Telegram Bot Token; 3) an OpenAI API Key. Then configure the Webhook, user validation fields, message router, and AI node credentials step by step. After setup, send a test text message via the test Webhook to verify the flow.