osint-mcp-server

censys_hosts

Search Censys to discover hosts matching your query. Get IP addresses, services, ports, location, and ASN for threat intelligence and attack surface mapping.

Instructions

Search Censys for hosts matching a query. Returns IPs, services, ports, location, ASN. Requires CENSYS_API_ID + CENSYS_API_SECRET.

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": {
      "query": "<query>"
    },
    "name": "censys_hosts"
  }
}

Input Schema

Name	Required	Description	Default
`query`	Yes	Censys search query
`per_page`	No	Results per page (max 100, default: 25)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.0Mar 17, 2026

TDQS

A4.2/5.0

Behavior4/5

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

No annotations provided, so description bears full burden. Discloses return fields and authentication requirement, but omits details like rate limits, pagination behavior, or error handling. Still informative for a simple search tool.

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?

Two concise sentences. Front-loaded with purpose, immediately followed by expected outputs and prerequisites. No wasted words.

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?

Given low parameter count, absence of output schema, and no nested objects, the description is nearly complete. Covers purpose, return fields, and authentication. Slight lack of behavioral details but adequate for this tool.

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%, so baseline is 3. Description does not add significant meaning beyond schema descriptions for query and per_page. The API key requirement is mentioned but not a parameter.

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?

Clearly states verb 'Search' and resource 'hosts', lists returned fields (IPs, services, ports, location, ASN). Differentiates from siblings like censys_certificates and censys_host_details.

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

Usage Guidelines4/5

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

Mentions required API keys as prerequisite, but lacks explicit when-to-use or when-not-to-use guidance relative to sibling tools. Context is implied by specifying Censys search host functionality.

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