OSINT MCP Server

st_whois

Perform enhanced WHOIS lookups to retrieve registrant, admin, and technical contacts for a domain using SecurityTrails data.

Instructions

Enhanced WHOIS lookup via SecurityTrails with registrant/admin/technical contacts. Requires ST_API_KEY.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "domain": "<domain>"
    },
    "name": "st_whois"
  }
}

Input Schema

Name	Required	Description	Default
`domain`	Yes	Domain to look up

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.0Jun 12, 2026

TDQS

A3.6/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It discloses the need for an API key and that it retrieves contacts, but does not mention rate limits, data freshness, or error handling. This adds some context but is not comprehensive.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence that efficiently communicates the core purpose and additional contact details, followed by a brief requirement. No filler or redundant text.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple single-parameter tool with no output schema, the description covers the basic purpose, source, and authorization requirement. It lacks details on output structure or edge cases, but is largely sufficient for an agent to understand and use the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with the single 'domain' parameter described. The description adds that the lookup is 'enhanced' and includes contacts, which provides extra context about the return value but does not elaborate on parameter format or validation beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool performs an 'Enhanced WHOIS lookup via SecurityTrails' and specifies it includes 'registrant/admin/technical contacts', which distinguishes it from sibling WHOIS tools like 'whois_domain'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description mentions the prerequisite 'Requires ST_API_KEY' but provides no guidance on when to use this tool versus alternatives such as 'whois_domain' or other lookup tools present in the sibling list.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.