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Building an AI-Powered Telegram Bot with Claude API and n8n: A Complete Guide

#n8n #automation #ai #tutorial

Build a production-ready AI chatbot on Telegram using Anthropic's Claude API and n8n in under 30 minutes, with zero traditional backend code.

Why Claude API + Telegram + n8n?

If you've ever wanted to deploy an AI assistant that real users can interact with instantly, you've probably faced a familiar dilemma: write a full backend from scratch, or cobble together fragile scripts that break at 3 AM.

There's a better way. By combining three tools — Claude API for intelligence, Telegram for the user interface, and n8n for orchestration — you get a production-grade chatbot with:

  • Claude 3.5 Sonnet / Claude 4 as the reasoning engine — far more nuanced than GPT for following complex instructions
  • Telegram as a zero-friction UI that 900M+ users already have installed
  • n8n as the glue layer — visual workflow automation that you self-host, so there are no per-execution fees like Zapier

I've been running this exact stack for OpenClaw, an AI-powered Telegram agent, and it handles thousands of messages daily without a single line of Express.js. Let me show you how to build it.

Prerequisites

Before we start, make sure you have:

Requirement Details
Node.js v18+ (required for n8n)
n8n Self-hosted or n8n Cloud account
Anthropic API Key Get one at console.anthropic.com
Telegram Account To create a bot via BotFather

Estimated cost: ~$0.003 per message with Claude 3.5 Sonnet. For most personal-use bots, you'll spend less than $5/month.

Step 1: Create Your Telegram Bot with BotFather

Open Telegram and search for @botfather. This is Telegram's official bot for creating bots.

/start
/newbot
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BotFather will ask two questions:

  1. Bot name: The display name (e.g., "My Claude Assistant")
  2. Bot username: Must end in bot (e.g., my_claude_assistant_bot)

You'll receive a Bot Token that looks like this:

7123456789:AAH_your-token-string-here
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Save this token — you'll need it in Step 3.

Optional but Recommended: Configure Bot Settings 

/setdescription - Add a description for your bot
/setabouttext   - Set the "About" section
/setuserpic     - Upload a profile picture
/setcommands    - Define command menu
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Here's a useful command list to set via /setcommands:

start - Start the bot
help - Show available commands
clear - Reset conversation context
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Step 2: Install and Set Up n8n

Option A: Self-Hosted (Recommended for Production) 

# Install n8n globally
npm install -g n8n

# Or use Docker (preferred for production)
docker run -d \
  --name n8n \
  -p 5678:5678 \
  -v n8n_data:/home/node/.n8n \
  -e WEBHOOK_URL=https://your-domain.com/ \
  n8nio/n8n
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Important: For Telegram webhooks to work, n8n must be accessible via HTTPS on a public URL. If you're developing locally, use a tunnel service like ngrok or cloudflared.

# Quick tunnel for local development
npx ngrok http 5678
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Option B: n8n Cloud

Sign up at app.n8n.cloud. The free tier gives you 2,500 executions/month — more than enough for testing. Webhooks work out of the box, no tunnel required.

Verify Installation

Open http://localhost:5678 (or your cloud URL). You should see the n8n canvas editor. Create a new workflow and name it "Claude Telegram Bot".

Step 3: Configure the Telegram Trigger Node

In your new workflow, click "Add first step" and search for Telegram.

Select "Telegram Trigger" — this node listens for incoming messages to your bot.

Configure Credentials

  1. Click "Create New Credential"
  2. Paste your Bot Token from Step 1
  3. Click "Save"

Trigger Settings

Setting Value
Updates message
Additional Fields Leave default

The node configuration JSON:

{
  "parameters": {
    "updates": ["message"]
  },
  "name": "Telegram Trigger",
  "type": "n8n-nodes-base.telegramTrigger",
  "typeVersion": 1.1,
  "position": [250, 300],
  "credentials": {
    "telegramApi": {
      "id": "YOUR_CREDENTIAL_ID",
      "name": "Telegram Bot"
    }
  }
}
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Test the Trigger

  1. Click "Listen for test event" in n8n
  2. Send any message to your bot on Telegram
  3. You should see the incoming message data appear in n8n

The payload includes message.text, message.chat.id, message.from.first_name, and more. We'll use these fields in subsequent steps.

Step 4: Connect the Claude API (Anthropic Node)

Add a new node after the Telegram Trigger. Search for "Anthropic" or "HTTP Request".

Option A: Using the Built-in Anthropic Node (n8n v1.30+)

n8n v1.30+ ships with a native Anthropic node. Configure it as follows:

  1. Credential: Add your Anthropic API key
  2. Model: claude-sonnet-4-20250514 (best balance of speed, quality, and cost)
  3. Prompt: Use an expression to inject the user's Telegram message: 
{{ $json.message.text }}
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Option B: Using HTTP Request Node (Any n8n Version)

If your n8n version doesn't have the native Anthropic node, the HTTP Request node works perfectly:

{
  "parameters": {
    "method": "POST",
    "url": "https://api.anthropic.com/v1/messages",
    "authentication": "genericCredentialType",
    "genericAuthType": "httpHeaderAuth",
    "sendHeaders": true,
    "headerParameters": {
      "parameters": [
        {
          "name": "x-api-key",
          "value": "YOUR_ANTHROPIC_API_KEY"
        },
        {
          "name": "anthropic-version",
          "value": "2023-06-01"
        },
        {
          "name": "content-type",
          "value": "application/json"
        }
      ]
    },
    "sendBody": true,
    "specifyBody": "json",
    "jsonBody": "={{ JSON.stringify({ model: 'claude-sonnet-4-20250514', max_tokens: 1024, system: 'You are a helpful AI assistant on Telegram. Keep responses concise and formatted for mobile reading. Use short paragraphs and bullet points when appropriate.', messages: [{ role: 'user', content: $json.message.text }] }) }}"
  },
  "name": "Claude API",
  "type": "n8n-nodes-base.httpRequest",
  "typeVersion": 4.2,
  "position": [500, 300]
}
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System Prompt Best Practices for Telegram Bots

The system prompt determines your bot's personality and behavior. Here's one that works well:

You are a helpful AI assistant on Telegram. Follow these rules:
1. Keep responses under 4096 characters (Telegram's message limit).
2. Use short paragraphs — mobile screens are small.
3. Use bullet points and numbered lists for structured information.
4. If a question is ambiguous, give the most likely answer first,
   then briefly mention alternatives.
5. Format code blocks with triple backticks and language identifiers.
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Step 5: Send the Response Back to Telegram

Add a "Telegram" node (the action node, not the Trigger) after the Claude API node.

Configuration

Setting Value
Resource Send Message
Chat ID {{ $('Telegram Trigger').item.json.message.chat.id }}
Text Depends on Step 4 method (see below)
Parse Mode Markdown

For the Text field:

If using the native Anthropic node:

{{ $json.message.content[0].text }}
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If using the HTTP Request node:

{{ $json.content[0].text }}
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Handle Long Responses

Telegram enforces a 4096-character limit per message. Add a Code node between Claude API and the Telegram send node to split long responses:

const text = $input.first().json.content[0].text;
const chatId = $('Telegram Trigger').first().json.message.chat.id;
const maxLength = 4000; // Leave buffer for Markdown formatting

if (text.length <= maxLength) {
  return [{ json: { chatId, text } }];
}

// Split into chunks at natural paragraph boundaries
const chunks = [];
let remaining = text;

while (remaining.length > 0) {
  if (remaining.length <= maxLength) {
    chunks.push(remaining);
    break;
  }

  let splitIndex = remaining.lastIndexOf('\n\n', maxLength);
  if (splitIndex === -1) splitIndex = remaining.lastIndexOf('\n', maxLength);
  if (splitIndex === -1) splitIndex = remaining.lastIndexOf(' ', maxLength);
  if (splitIndex === -1) splitIndex = maxLength;

  chunks.push(remaining.substring(0, splitIndex));
  remaining = remaining.substring(splitIndex).trimStart();
}

return chunks.map(chunk => ({ json: { chatId, text: chunk } }));
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Then update the Telegram send node to use {{ $json.text }} for the text and {{ $json.chatId }} for the chat ID.

Step 6: Error Handling and Fallback

Production bots need graceful error handling. Here's how to make yours resilient.

Add an Error Trigger Workflow

Create a separate workflow called "Bot Error Handler":

  1. Add an Error Trigger node
  2. Connect it to a Telegram Send Message node
  3. Configure the error message: 
Sorry, I encountered an error processing your request.
Please try again in a moment.

If this persists, use /clear to reset the conversation.
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Rate Limiting

Claude API has rate limits, and users sometimes spam messages. Add a Code node before the API call:

const chatId = $json.message.chat.id;
const now = Date.now();
const rateLimitMs = 2000; // Minimum 2 seconds between messages

// Use n8n's static data for cross-execution persistence
const state = $getWorkflowStaticData('global');
const key = 'lastMsg_' + chatId;

if (state[key] && (now - state[key]) < rateLimitMs) {
  return []; // Skip processing — too fast
}

state[key] = now;
return [$input.first()];
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API Error Detection

Add an IF node after the Claude API call to check for errors:

  • Condition: {{ $json.error ? true : false }}
  • True branch: Send an apologetic fallback message to the user
  • False branch: Continue to the response formatting and Telegram send node

Input Validation

Add another Code node before the API call to filter out non-text messages:

const message = $json.message;

// Skip if no text content (e.g., stickers, images, etc.)
if (!message.text || message.text.trim() === '') {
  return [];
}

// Skip bot commands that should be handled separately
if (message.text.startsWith('/clear') || message.text.startsWith('/help')) {
  return [];
}

return [$input.first()];
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Step 7: Deployment and Production Tips

Use a VPS for Self-Hosting

A $6/month DigitalOcean droplet (or equivalent) is ideal. Here's a production-ready Docker Compose configuration:

version: '3.8'

services:
  n8n:
    image: n8nio/n8n
    restart: always
    ports:
      - "5678:5678"
    environment:
      - N8N_HOST=your-domain.com
      - N8N_PORT=5678
      - N8N_PROTOCOL=https
      - WEBHOOK_URL=https://your-domain.com/
      - NODE_ENV=production
      - N8N_ENCRYPTION_KEY=your-random-encryption-key
      - ANTHROPIC_API_KEY=sk-ant-xxxxx
    volumes:
      - n8n_data:/home/node/.n8n

  caddy:
    image: caddy:2
    restart: always
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./Caddyfile:/etc/caddy/Caddyfile
      - caddy_data:/data

volumes:
  n8n_data:
  caddy_data:
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Caddyfile for automatic HTTPS:

your-domain.com {
    reverse_proxy n8n:5678
}
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Deploy with:

docker compose up -d
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Caddy automatically provisions and renews SSL certificates via Let's Encrypt. No manual HTTPS configuration needed.

Monitoring

Create a separate n8n workflow with a Schedule Trigger (every 5 minutes) that pings your bot and alerts you if it's down. Route the alert branch to your personal Telegram, email, or Slack.

Cost Optimization Strategies

Strategy Estimated Savings
Cache frequent questions with a Redis or Postgres lookup 30-50% fewer API calls
Route simple queries to claude-3-haiku, complex ones to claude-sonnet-4-20250514 ~60% cost reduction
Set max_tokens based on expected response length Prevents paying for unused token capacity
Add a "typing..." indicator while Claude processes Improves UX, reduces duplicate messages

Complete Workflow JSON (Import-Ready)

Here's the full n8n workflow you can import directly into your instance:

{
  "name": "Claude Telegram Bot",
  "nodes": [
    {
      "parameters": {
        "updates": ["message"]
      },
      "name": "Telegram Trigger",
      "type": "n8n-nodes-base.telegramTrigger",
      "typeVersion": 1.1,
      "position": [250, 300],
      "credentials": {
        "telegramApi": {
          "id": "1",
          "name": "Telegram Bot"
        }
      }
    },
    {
      "parameters": {
        "method": "POST",
        "url": "https://api.anthropic.com/v1/messages",
        "authentication": "genericCredentialType",
        "genericAuthType": "httpHeaderAuth",
        "sendHeaders": true,
        "headerParameters": {
          "parameters": [
            { "name": "x-api-key", "value": "={{ $env.ANTHROPIC_API_KEY }}" },
            { "name": "anthropic-version", "value": "2023-06-01" },
            { "name": "content-type", "value": "application/json" }
          ]
        },
        "sendBody": true,
        "specifyBody": "json",
        "jsonBody": "={{ JSON.stringify({ model: 'claude-sonnet-4-20250514', max_tokens: 1024, system: 'You are a helpful AI assistant on Telegram. Keep responses concise and formatted for mobile reading.', messages: [{ role: 'user', content: $json.message.text }] }) }}"
      },
      "name": "Claude API",
      "type": "n8n-nodes-base.httpRequest",
      "typeVersion": 4.2,
      "position": [500, 300],
      "credentials": {
        "httpHeaderAuth": {
          "id": "2",
          "name": "Anthropic API"
        }
      }
    },
    {
      "parameters": {
        "chatId": "={{ $('Telegram Trigger').item.json.message.chat.id }}",
        "text": "={{ $json.content[0].text }}",
        "additionalFields": {
          "parse_mode": "Markdown"
        }
      },
      "name": "Send Response",
      "type": "n8n-nodes-base.telegram",
      "typeVersion": 1.2,
      "position": [750, 300],
      "credentials": {
        "telegramApi": {
          "id": "1",
          "name": "Telegram Bot"
        }
      }
    }
  ],
  "connections": {
    "Telegram Trigger": {
      "main": [[{ "node": "Claude API", "type": "main", "index": 0 }]]
    },
    "Claude API": {
      "main": [[{ "node": "Send Response", "type": "main", "index": 0 }]]
    }
  }
}
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To import: In n8n, go to Workflows > Import from File/URL and paste this JSON.

What's Next

Once your basic bot is running, here are the most impactful enhancements:

  1. Conversation memory — Store chat history in Postgres or Redis, and send previous messages as context to Claude for multi-turn conversations
  2. Tool use — Leverage Claude's function calling to let your bot search the web, check weather, query databases, or call external APIs
  3. Multi-modal input — Handle images sent to the bot using Claude's vision capabilities
  4. User authentication — Restrict access to authorized Telegram user IDs using an allowlist
  5. Analytics dashboard — Log all interactions to Google Sheets or a database for usage insights

I'm building all of these into OpenClaw. Follow me for the next article in this series.

Wrapping Up

The Claude API + Telegram + n8n stack is one of the fastest paths from idea to production AI bot. You get Claude's reasoning quality, Telegram's massive user base, and n8n's visual workflow builder — all without writing a traditional backend.

Total cost: ~$6/month for a VPS plus a few dollars in API usage. Compare that to enterprise chatbot platforms charging $200+/month.

The complete workflow JSON above is ready to import. Add your API keys, and you'll have a working AI bot in under 30 minutes.

If this was helpful, drop a reaction and follow me for Part 2 where we add conversation memory and Claude's tool-use capabilities.

Ryosuke Matsumiya — AI Automation Engineer. Building OpenClaw, an AI-powered Telegram agent. Passionate about n8n, Claude API, and workflow automation.

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