Is the SecurityTrails API free to use?

SecurityTrails offers a Free Tier API plan which allows 50 API requests per month. This is excellent for specific, targeted OSINT investigations. For automated or large-scale recon, you would need a commercial subscription.

What is historical DNS good for?

Companies often migrate infrastructure and hide behind WAFs like Cloudflare. Historical DNS reveals the original origin IP addresses used before the WAF was implemented, which might still be active and vulnerable to direct attacks. It's a critical tool in penetration testing.

How can I find related domains for a target company?

Use the `get_associated_domains` tool. It uses proprietary correlation to find other domains owned by the same entity. You can also use `get_domains_by_ip` to find what else is hosted on their IP space.

SecurityTrails MCP Server for LangChain 10 tools — connect in under 2 minutes

Name: SecurityTrails
Availability: InStock
Author: Vinkius

python.langchain.com/docs/integrations/tools/mcp

Built by Vinkius GDPR 10 Tools Framework

LangChain is the leading Python framework for composable LLM applications. Connect SecurityTrails through Vinkius and LangChain agents can call every tool natively. combine them with retrievers, memory, and output parsers for sophisticated AI pipelines.

Get MCP Server for AI Agents

ASK AI ABOUT THIS MCP SERVER

Open in ChatGPT Open in Claude Open in Perplexity

Vinkius supports streamable HTTP and SSE.

python

import asyncio
from langchain_mcp_adapters.client import MultiServerMCPClient
from langchain_openai import ChatOpenAI
from langgraph.prebuilt import create_react_agent

async def main():
    # Your Vinkius token. get it at cloud.vinkius.com
    async with MultiServerMCPClient({
        "securitytrails": {
            "transport": "streamable_http",
            "url": "https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp",
        }
    }) as client:
        tools = client.get_tools()
        agent = create_react_agent(
            ChatOpenAI(model="gpt-4o"),
            tools,
        )
        response = await agent.ainvoke({
            "messages": [{
                "role": "user",
                "content": "Using SecurityTrails, show me what tools are available.",
            }]
        })
        print(response["messages"][-1].content)

asyncio.run(main())

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Stream every event to Splunk, Datadog, or your own webhook in real-time

* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure

About SecurityTrails MCP Server

Connect your SecurityTrails account to any AI agent and empower your OSINT, bug bounty, and threat intelligence workflows with the world's most comprehensive domain and IP database.

LangChain's ecosystem of 500+ components combines seamlessly with SecurityTrails through native MCP adapters. Connect 10 tools via Vinkius and use ReAct agents, Plan-and-Execute strategies, or custom agent architectures. with LangSmith tracing giving full visibility into every tool call, latency, and token cost.

What you can do

Attack Surface Mapping — Instantly enumerate all subdomains for any target organization to map their external footprint
Historical DNS Analysis — Look back in time at DNS records (A, MX, NS, TXT) to find hidden infrastructure, bypassed firewalls, or legacy systems
Reverse IP Lookups — Find all domains hosted on a specific IP address to identify shared hosting or related corporate assets
Advanced Threat Hunting — Use the SecurityTrails DSL (Domain Specific Language) to query the entire internet for specific tech stacks or vulnerable infrastructure
Ownership Intelligence — Access current and historical WHOIS records to track domain ownership changes and unmask hidden threat actors
Corporate Associations — Discover domains strongly associated with your primary target to expand your investigation scope

The SecurityTrails MCP Server exposes 10 tools through the Vinkius. Connect it to LangChain in under two minutes — no API keys to rotate, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.

How to Connect SecurityTrails to LangChain via MCP

Follow these steps to integrate the SecurityTrails MCP Server with LangChain.

Install dependencies

Run pip install langchain langchain-mcp-adapters langgraph langchain-openai

Replace the token

Replace [YOUR_TOKEN_HERE] with your Vinkius token

Run the agent

Save the code and run python agent.py

Explore tools

The agent discovers 10 tools from SecurityTrails via MCP

Why Use LangChain with the SecurityTrails MCP Server

LangChain provides unique advantages when paired with SecurityTrails through the Model Context Protocol.

The largest ecosystem of integrations, chains, and agents. combine SecurityTrails MCP tools with 500+ LangChain components

Agent architecture supports ReAct, Plan-and-Execute, and custom strategies with full MCP tool access at every step

LangSmith tracing gives you complete visibility into tool calls, latencies, and token usage for production debugging

Memory and conversation persistence let agents maintain context across SecurityTrails queries for multi-turn workflows

SecurityTrails + LangChain Use Cases

Practical scenarios where LangChain combined with the SecurityTrails MCP Server delivers measurable value.

RAG with live data: combine SecurityTrails tool results with vector store retrievals for answers grounded in both real-time and historical data

Autonomous research agents: LangChain agents query SecurityTrails, synthesize findings, and generate comprehensive research reports

Multi-tool orchestration: chain SecurityTrails tools with web scrapers, databases, and calculators in a single agent run

Production monitoring: use LangSmith to trace every SecurityTrails tool call, measure latency, and optimize your agent's performance

SecurityTrails MCP Tools for LangChain (10)

These 10 tools become available when you connect SecurityTrails to LangChain via MCP:

get_api_usage

Check current SecurityTrails API quota usage

get_associated_domains

Great for expanding the scope of an investigation. Find other domains associated with a target domain

get_dns_history

Useful for finding old IPs that might still be hosting vulnerable software, or tracking infrastructure migration over time. Retrieve historical DNS records for a domain

get_domain_details

Essential for mapping out a target domain's existing infrastructure. Get complete domain intelligence and current DNS records

get_domain_tags

Get classification tags for a domain

get_domains_by_ip

Essential for understanding shared hosting environments or identifying hidden vhosts. Find all domains pointed to a specific IP address

get_subdomains

Critical for attack surface mapping and asset discovery. Returns both active and inactive subdomains. Discover all subdomains for a given domain

get_whois

Get current WHOIS information for a domain

get_whois_history

Useful for OSINT investigations to uncover historical owners before privacy protection was enabled. Retrieve historical WHOIS records for a domain

search_dsl

Examples: `ipv4="1.1.1.1" AND mx="alt1.aspmx.l.google.com"` or `whois_email="admin@example.com"`. Check SecurityTrails docs for full DSL syntax. Advanced search using SecurityTrails DSL

Example Prompts for SecurityTrails in LangChain

Ready-to-use prompts you can give your LangChain agent to start working with SecurityTrails immediately.

"Find all subdomains for tesla.com."

"Check the historical 'A' records for example.com. Were there any changes in 2021?"

"What domains are hosted on the IP 8.8.8.8?"

Troubleshooting SecurityTrails MCP Server with LangChain

Common issues when connecting SecurityTrails to LangChain through the Vinkius, and how to resolve them.

MultiServerMCPClient not found

Install: pip install langchain-mcp-adapters

SecurityTrails + LangChain FAQ

Common questions about integrating SecurityTrails MCP Server with LangChain.

How does LangChain connect to MCP servers?

Use langchain-mcp-adapters to create an MCP client. LangChain discovers all tools and wraps them as native LangChain tools compatible with any agent type.

Which LangChain agent types work with MCP?

All agent types including ReAct, OpenAI Functions, and custom agents work with MCP tools. The tools appear as standard LangChain tools after the adapter wraps them.