How to integrate Nextdns MCP with LlamaIndex

This guide walks you through connecting Nextdns to LlamaIndex using the Composio tool router. By the end, you'll have a working Nextdns agent that can block access to adult websites for a profile, download dns logs from last week, show top domains queried by your devices through natural language commands. This guide will help you understand how to give your LlamaIndex agent real control over a Nextdns account through Composio's Nextdns MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Nextdns logoNextdns
Api Key

NextDNS is a DNS service that blocks malicious sites, ads, and trackers before they reach your device. It boosts your internet security and privacy with real-time protection and granular control.

68 Tools

Introduction

This guide walks you through connecting Nextdns to LlamaIndex using the Composio tool router. By the end, you'll have a working Nextdns agent that can block access to adult websites for a profile, download dns logs from last week, show top domains queried by your devices through natural language commands.

This guide will help you understand how to give your LlamaIndex agent real control over a Nextdns account through Composio's Nextdns MCP server.

Before we dive in, let's take a quick look at the key ideas and tools involved.

Also integrate Nextdns with

TL;DR

Here's what you'll learn:
  • Set your OpenAI and Composio API keys
  • Install LlamaIndex and Composio packages
  • Create a Composio Tool Router session for Nextdns
  • Connect LlamaIndex to the Nextdns MCP server
  • Build a Nextdns-powered agent using LlamaIndex
  • Interact with Nextdns through natural language

What is LlamaIndex?

LlamaIndex is a data framework for building LLM applications. It provides tools for connecting LLMs to external data sources and services through agents and tools.

Key features include:

  • ReAct Agent: Reasoning and acting pattern for tool-using agents
  • MCP Tools: Native support for Model Context Protocol
  • Context Management: Maintain conversation context across interactions
  • Async Support: Built for async/await patterns

What is the Nextdns MCP server, and what's possible with it?

The Nextdns MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Nextdns account. It provides structured and secure access to your DNS security and privacy controls, so your agent can perform actions like blocking domains, managing profiles, analyzing DNS analytics, and clearing logs on your behalf.

  • Dynamic domain and TLD blocking: Instantly add domains or top-level domains to your denylist or security blocklist, helping you stay ahead of new threats.
  • Profile management and configuration: Create, update, or delete NextDNS configuration profiles to tailor DNS filtering and security settings for different users or devices.
  • Comprehensive DNS analytics: Retrieve detailed analytics by device, domain, or client IP to monitor DNS activity, spot anomalies, and optimize security policies.
  • Log management and export: Download DNS query logs for audit or troubleshooting, or clear logs entirely to maintain your privacy.
  • Control over block page settings: Enable or disable the block page for any configuration, giving you flexibility over how blocks are displayed to users.

What is the Composio tool router, and how does it fit here?

What is Composio SDK?

Composio's Composio SDK helps agents find the right tools for a task at runtime. You can plug in multiple toolkits (like Gmail, HubSpot, and GitHub), and the agent will identify the relevant app and action to complete multi-step workflows. This can reduce token usage and improve the reliability of tool calls. Read more here: Getting started with Composio SDK

The tool router generates a secure MCP URL that your agents can access to perform actions.

How the Composio SDK works

The Composio SDK follows a three-phase workflow:

  1. Discovery: Searches for tools matching your task and returns relevant toolkits with their details.
  2. Authentication: Checks for active connections. If missing, creates an auth config and returns a connection URL via Auth Link.
  3. Execution: Executes the action using the authenticated connection.

Step-by-step Guide

Step by step10 STEPS
1

Prerequisites

Before you begin, make sure you have:
  • Python 3.8/Node 16 or higher installed
  • A Composio account with the API key
  • An OpenAI API key
  • A Nextdns account and project
  • Basic familiarity with async Python/Typescript
2

Getting API Keys for OpenAI, Composio, and Nextdns

OpenAI API key (OPENAI_API_KEY)
  • Go to the OpenAI dashboard
  • Create an API key if you don't have one
  • Assign it to OPENAI_API_KEY in .env
Composio API key and user ID
  • Log into the Composio dashboard
  • Copy your API key from Settings
    • Use this as COMPOSIO_API_KEY
  • Pick a stable user identifier (email or ID)
    • Use this as COMPOSIO_USER_ID
3

Installing dependencies

npm install @composio/llamaindex @llamaindex/openai @llamaindex/tools @llamaindex/workflow dotenv

Create a new Typescript project and install the necessary dependencies:

  • @composio/llamaindex: Composio's LlamaIndex integration
  • @llamaindex/openai: OpenAI LLM integration
  • @llamaindex/tools: MCP client for LlamaIndex
  • @llamaindex/workflow: Workflow framework for LlamaIndex
  • dotenv: Environment variable management
4

Set environment variables

bash
OPENAI_API_KEY=your-openai-api-key
COMPOSIO_API_KEY=your-composio-api-key
COMPOSIO_USER_ID=your-user-id

Create a .env file in your project root:

These credentials will be used to:

  • Authenticate with OpenAI's GPT-5 model
  • Connect to Composio's Tool Router
  • Identify your Composio user session for Nextdns access
5

Import modules

import "dotenv/config";
import readline from "node:readline/promises";
import { stdin as input, stdout as output } from "node:process";

import { Composio } from "@composio/core";

import { mcp } from "@llamaindex/tools";
import { agent as createAgent } from "@llamaindex/workflow";
import { openai } from "@llamaindex/openai";

dotenv.config();

Create a new file called nextdns_llamaindex_agent.ts and import the required modules:

Key imports:

  • dotenv.config loads .env at runtime
  • readline gives us a simple CLI chat loop
  • Composio is the main Composio SDK client
  • mcp connects to an MCP endpoint
  • createAgent builds a LlamaIndex agent
  • openai configures the LLM backend
6

Load environment variables and initialize Composio

const OPENAI_API_KEY = process.env.OPENAI_API_KEY;
const COMPOSIO_API_KEY = process.env.COMPOSIO_API_KEY;
const COMPOSIO_USER_ID = process.env.COMPOSIO_USER_ID;

if (!OPENAI_API_KEY) throw new Error("OPENAI_API_KEY is not set");
if (!COMPOSIO_API_KEY) throw new Error("COMPOSIO_API_KEY is not set");
if (!COMPOSIO_USER_ID) throw new Error("COMPOSIO_USER_ID is not set");

What's happening:

This ensures missing credentials cause early, clear errors before the agent attempts to initialise.

7

Create a Tool Router session and build the agent function

async function buildAgent() {

  console.log(`Initializing Composio client...${COMPOSIO_USER_ID!}...`);
  console.log(`COMPOSIO_USER_ID: ${COMPOSIO_USER_ID!}...`);

  const composio = new Composio({
    apiKey: COMPOSIO_API_KEY,
    provider: new LlamaindexProvider(),
  });

  const session = await composio.create(
    COMPOSIO_USER_ID!,
    {
      toolkits: ["nextdns"],
    },
  );

  const mcpUrl = session.mcp.url;
  console.log(`Composio Tool Router MCP URL: ${mcpUrl}`);

  const server = mcp({
    url: mcpUrl,
    clientName: "composio_tool_router_with_llamaindex",
    requestInit: {
      headers: {
        "x-api-key": COMPOSIO_API_KEY!,
      },
    },
    // verbose: true,
  });

  const tools = await server.tools();

  const llm = openai({ apiKey: OPENAI_API_KEY, model: "gpt-5" });

  const agent = createAgent({
    name: "composio_tool_router_with_llamaindex",
        description : "An agent that uses Composio Tool Router MCP tools to perform actions.",
    systemPrompt:
      "You are a helpful assistant connected to Composio Tool Router."+
"Use the available tools to answer user queries and perform Nextdns actions." ,
    llm,
    tools,
  });

  return agent;
}

What's happening here:

  • We create a Composio client using your API key and configure it with the LlamaIndex provider
  • We then create a tool router MCP session for your user, specifying the toolkits we want to use (in this case, nextdns)
  • The session returns an MCP HTTP endpoint URL that acts as a gateway to all your configured tools
  • LlamaIndex will connect to this endpoint to dynamically discover and use the available Nextdns tools.
  • The MCP tools are mapped to LlamaIndex-compatible tools and plug them into the Agent.
8

Create an interactive chat loop

async function chatLoop(agent: ReturnType<typeof createAgent>) {
  const rl = readline.createInterface({ input, output });

  console.log("Type 'quit' or 'exit' to stop.");

  while (true) {
    let userInput: string;

    try {
      userInput = (await rl.question("\nYou: ")).trim();
    } catch {
      console.log("\nAgent: Bye!");
      break;
    }

    if (!userInput) {
      continue;
    }

    const lower = userInput.toLowerCase();
    if (lower === "quit" || lower === "exit") {
      console.log("Agent: Bye!");
      break;
    }

    try {
      process.stdout.write("Agent: ");

      const stream = agent.runStream(userInput);
      let finalResult: any = null;

      for await (const event of stream) {
        // The event.data contains the streamed content
        const data: any = event.data;

        // Check for streaming delta content
        if (data?.delta) {
          process.stdout.write(data.delta);
        }

        // Store final result for fallback
        if (data?.result || data?.message) {
          finalResult = data;
        }
      }

      // If no streaming happened, show the final result
      if (finalResult) {
        const answer =
          finalResult.result ??
          finalResult.message?.content ??
          finalResult.message ??
          "";
        if (answer && typeof answer === "string" && !answer.includes("[object")) {
          process.stdout.write(answer);
        }
      }

      console.log(); // New line after streaming completes
    } catch (err: any) {
      console.error("\nAgent error:", err?.message ?? err);
    }
  }

  rl.close();
}

What's happening:

  • We're creating a direct terminal interface to chat with Nextdns
  • The LLM's responses are streamed to the CLI for faster interaction.
  • The agent uses context to maintain conversation history
  • The agent processes the request, selects appropriate Nextdns tools, and returns a result
  • We extract the answer from the result data structure and display it to the user
  • You can type 'quit' or 'exit' to stop the chat loop gracefully
  • Agent responses and any errors are streamed in a clear, readable format
9

Define the main entry point

async function main() {
  try {
    const agent = await buildAgent();
    await chatLoop(agent);
  } catch (err) {
    console.error("Failed to start agent:", err);
    process.exit(1);
  }
}

main();

What's happening here:

  • We're orchestrating the entire application flow
  • The agent gets built with proper error handling
  • Then we kick off the interactive chat loop so you can start talking to Nextdns
10

Run the agent

npx ts-node llamaindex-agent.ts

When prompted, authenticate and authorise your agent with Nextdns, then start asking questions.

Complete Code

Here's the complete code to get you started with Nextdns and LlamaIndex:

import "dotenv/config";
import readline from "node:readline/promises";
import { stdin as input, stdout as output } from "node:process";

import { Composio } from "@composio/core";
import { LlamaindexProvider } from "@composio/llamaindex";

import { mcp } from "@llamaindex/tools";
import { agent as createAgent } from "@llamaindex/workflow";
import { openai } from "@llamaindex/openai";

dotenv.config();

const OPENAI_API_KEY = process.env.OPENAI_API_KEY;
const COMPOSIO_API_KEY = process.env.COMPOSIO_API_KEY;
const COMPOSIO_USER_ID = process.env.COMPOSIO_USER_ID;

if (!OPENAI_API_KEY) {
    throw new Error("OPENAI_API_KEY is not set in the environment");
  }
if (!COMPOSIO_API_KEY) {
    throw new Error("COMPOSIO_API_KEY is not set in the environment");
  }
if (!COMPOSIO_USER_ID) {
    throw new Error("COMPOSIO_USER_ID is not set in the environment");
  }

async function buildAgent() {

  console.log(`Initializing Composio client...${COMPOSIO_USER_ID!}...`);
  console.log(`COMPOSIO_USER_ID: ${COMPOSIO_USER_ID!}...`);

  const composio = new Composio({
    apiKey: COMPOSIO_API_KEY,
    provider: new LlamaindexProvider(),
  });

  const session = await composio.create(
    COMPOSIO_USER_ID!,
    {
      toolkits: ["nextdns"],
    },
  );

  const mcpUrl = session.mcp.url;
  console.log(`Composio Tool Router MCP URL: ${mcpUrl}`);

  const server = mcp({
    url: mcpUrl,
    clientName: "composio_tool_router_with_llamaindex",
    requestInit: {
      headers: {
        "x-api-key": COMPOSIO_API_KEY!,
      },
    },
    // verbose: true,
  });

  const tools = await server.tools();

  const llm = openai({ apiKey: OPENAI_API_KEY, model: "gpt-5" });

  const agent = createAgent({
    name: "composio_tool_router_with_llamaindex",
    description:
      "An agent that uses Composio Tool Router MCP tools to perform actions.",
    systemPrompt:
      "You are a helpful assistant connected to Composio Tool Router."+
"Use the available tools to answer user queries and perform Nextdns actions." ,
    llm,
    tools,
  });

  return agent;
}

async function chatLoop(agent: ReturnType<typeof createAgent>) {
  const rl = readline.createInterface({ input, output });

  console.log("Type 'quit' or 'exit' to stop.");

  while (true) {
    let userInput: string;

    try {
      userInput = (await rl.question("\nYou: ")).trim();
    } catch {
      console.log("\nAgent: Bye!");
      break;
    }

    if (!userInput) {
      continue;
    }

    const lower = userInput.toLowerCase();
    if (lower === "quit" || lower === "exit") {
      console.log("Agent: Bye!");
      break;
    }

    try {
      process.stdout.write("Agent: ");

      const stream = agent.runStream(userInput);
      let finalResult: any = null;

      for await (const event of stream) {
        // The event.data contains the streamed content
        const data: any = event.data;

        // Check for streaming delta content
        if (data?.delta) {
          process.stdout.write(data.delta);
        }

        // Store final result for fallback
        if (data?.result || data?.message) {
          finalResult = data;
        }
      }

      // If no streaming happened, show the final result
      if (finalResult) {
        const answer =
          finalResult.result ??
          finalResult.message?.content ??
          finalResult.message ??
          "";
        if (answer && typeof answer === "string" && !answer.includes("[object")) {
          process.stdout.write(answer);
        }
      }

      console.log(); // New line after streaming completes
    } catch (err: any) {
      console.error("\nAgent error:", err?.message ?? err);
    }
  }

  rl.close();
}

async function main() {
  try {
    const agent = await buildAgent();
    await chatLoop(agent);
  } catch (err: any) {
    console.error("Failed to start agent:", err?.message ?? err);
    process.exit(1);
  }
}

main();

Conclusion

You've successfully connected Nextdns to LlamaIndex through Composio's Tool Router MCP layer. Key takeaways:
  • Tool Router dynamically exposes Nextdns tools through an MCP endpoint
  • LlamaIndex's ReActAgent handles reasoning and orchestration; Composio handles integrations
  • The agent becomes more capable without increasing prompt size
  • Async Python provides clean, efficient execution of agent workflows
You can easily extend this to other toolkits like Gmail, Notion, Stripe, GitHub, and more by adding them to the toolkits parameter.
TOOLS

Supported Tools

Every Nextdns action and event your agent gets out of the box.

Add Allowlist Entry

Tool to add a domain to the allowlist of a NextDNS profile.

Add Blocked TLD

Tool to add a top-level domain to the security blocklist for a NextDNS profile.

Add Denylist Domain

Tool to add a domain to the denylist of a NextDNS profile.

Add Parental Control Category

Tool to add a content category to the parental control categories list.

Add Parental Control Service

Tool to add a service to the parental control services list of a NextDNS profile.

Add Privacy Blocklist

Tool to add a blocklist to the privacy blocklists for a NextDNS profile.

Add Privacy Native Tracker

Tool to add a native tracking service to the blocked list for a NextDNS profile.

Add DNS Rewrite Rule

Tool to add a DNS rewrite rule to a NextDNS profile.

Clear Logs

Tool to clear DNS logs for a NextDNS profile.

Create Profile

This tool allows users to create a new NextDNS profile.

Delete Allowlist Entry

Tool to remove a domain from a NextDNS profile's allowlist.

Delete NextDNS Configuration

Tool to delete a NextDNS configuration profile.

Delete Parental Control Category

Tool to remove a category from parental control blocked categories.

Delete Parental Control Service

Tool to remove a service from parental control blocked services.

Delete Privacy Blocklist

Tool to remove a blocklist from the privacy blocklists for a NextDNS profile.

Delete Privacy Native Tracker

Tool to remove a native tracking entry from a NextDNS profile's privacy settings.

Delete DNS Rewrite Rule

Tool to delete a DNS rewrite rule from a NextDNS profile.

Download Logs

Retrieves the download URL for exported DNS query logs from a NextDNS profile.

Get Allowlist

Tool to retrieve the list of allowed domains for a NextDNS profile.

Get Analytics Destinations

Tool to retrieve destination analytics for a profile showing query destinations by country or GAFAM company.

Get Analytics Devices

Tool to retrieve device analytics for a profile showing identified devices with names, models, and query counts.

Get Analytics DNSSEC

Tool to retrieve DNSSEC validation analytics for a profile showing validated vs non-validated query counts.

Get Analytics Domains

Tool to retrieve analytics data for domains within a specific profile.

Get Analytics Encryption

Tool to retrieve encryption analytics for a profile showing encrypted vs unencrypted query counts.

Get Analytics IPs

Tool to retrieve analytics aggregated by client IP addresses.

Get Analytics IP Versions

Tool to retrieve analytics grouped by IP version within a specific profile.

Get Analytics Protocols

Tool to retrieve protocol analytics for a specific profile showing DNS protocol distribution (DNS-over-HTTPS, DNS-over-TLS, UDP).

Get Analytics Query Types

Tool to retrieve DNS query counts broken down by query type.

Get Analytics Blocking Reasons

Tool to retrieve blocking reasons analytics showing blocklists, native tracking protection, and other reasons for blocked queries.

Get Analytics Status

Tool to retrieve analytics status for a specific profile.

Get Logs

Tool to retrieve logs for a specific NextDNS profile with optional filters.

Get Parental Control Settings

Tool to get parental control settings for a profile.

Get Parental Control Categories

Tool to get the list of blocked/allowed content categories for parental control.

Get Parental Control Services

Tool to get the list of blocked/allowed services for parental control.

Get Performance Settings

Tool to get performance settings for a profile including ECS, cache boost, and CNAME flattening configuration.

Get Privacy Settings

Tool to get privacy settings for a profile including blocklists, native tracking settings, disguised trackers, and affiliate settings.

Get Profile Details

Retrieves the details of a specific NextDNS profile.

Get DNS Rewrites

Tool to retrieve the list of DNS rewrites for a NextDNS profile.

Get Security TLDs

Tool to get the list of blocked TLDs (top-level domains) for a profile's security settings.

Get Profile Settings

Tool to get all settings for a NextDNS profile including logs, block page, performance, and web3 settings.

Get Block Page Settings

Tool to retrieve the block page settings for a NextDNS profile.

Get Logging Settings

Tool to retrieve the logging settings for a NextDNS profile.

List Denylist Domains

Tool to list domains in the denylist for a profile.

List Profiles

List all NextDNS profiles for the authenticated user, returning profile IDs and configurations.

List Security Settings

Tool to list current security options for a NextDNS configuration.

Log Client IPs

Tool to enable or disable logging of client IPs for a NextDNS configuration.

Toggle Domain Logging

Tool to enable or disable logging of domains for a NextDNS profile.

Remove Blocked TLD

Tool to remove a top-level domain from the security blocklist for a NextDNS profile.

Remove Denylist Domain

Removes a domain from a NextDNS profile's denylist (blocklist).

Rename Configuration

Tool to rename a NextDNS configuration (profile).

Replace Allowlist

Tool to replace the entire allowlist for a NextDNS profile.

Replace Denylist

Tool to replace the entire denylist (blocked domains) for a NextDNS profile.

Replace Parental Control Categories

Tool to replace the entire list of blocked/allowed content categories for parental control.

Replace Parental Control Services

Tool to replace the entire list of blocked/allowed services for parental control.

Replace Privacy Blocklists

Tool to replace the entire list of privacy blocklists for a NextDNS profile.

Replace Privacy Native Tracking Services

Tool to replace the entire list of blocked native tracking services for a NextDNS profile.

Replace Security TLDs

Tool to replace the entire list of blocked TLDs (top-level domains) for a NextDNS profile's security settings.

Update Allowlist Entry

Tool to update a specific allowlist entry in a NextDNS profile.

Update Denylist Entry

Updates a specific denylist entry in a NextDNS profile, typically to toggle its active status.

Update linked IP

Updates the linked IP address for a NextDNS profile to the current caller's public IP.

Update Parental Control Settings

Tool to update parental control settings for a NextDNS profile.

Update Parental Control Category

Tool to update a specific category entry in parental control settings.

Update Parental Control Service

Tool to update a specific service entry in parental control settings.

Update Performance Settings

Tool to update performance settings of a NextDNS profile.

Update Privacy Settings

Tool to update privacy settings for a profile.

Update Security Settings

Tool to update security settings for a profile.

Update Settings

Tool to update settings for a NextDNS profile including logs, block page, performance, and web3 settings.

Update Block Page Settings

Tool to update block page settings for a NextDNS profile.

FAQ

Frequently asked questions

With a standalone Nextdns MCP server, the agents and LLMs can only access a fixed set of Nextdns tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Nextdns and many other apps based on the task at hand, all through a single MCP endpoint.

Yes, you can. LlamaIndex fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Nextdns tools.

Yes, absolutely. You can configure which Nextdns scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Nextdns data and credentials are handled as safely as possible.

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