darknet-mcp-server

breachSearch

Search data breaches by email or username via HaveIBeenPwned to check if an account was exposed.

Instructions

Search all data breaches for a specific account (email or username) via HaveIBeenPwned. Requires HIBP_API_KEY (paid endpoint).

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": {
      "account": "<account>"
    },
    "name": "breachSearch"
  }
}

Input Schema

Name	Required	Description
`account`	Yes	The email address or username to search for
`truncateResponse`	No	If true, only return breach names (not full details). Default false.
`includeUnverified`	No	If true, include unverified breaches. Default false.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Jun 23, 2026

TDQS

A4/5.0

Behavior3/5

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

With no annotations, the description adds valuable operational context by mentioning the paid HIBP_API_KEY requirement. However, it does not disclose rate limits, response format, or failure behavior, leaving some behavioral aspects unspecified.

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 only two sentences, front-loaded with the purpose and followed by a critical prerequisite. Every word earns its place with no redundancy.

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?

The description is adequate for a straightforward search tool, covering the core action and a key requirement. The lack of an output schema is mitigated by the tool's simplicity, though return value expectations are not explicitly stated.

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?

All three parameters are fully described in the schema (100% coverage), so the description adds little extra meaning. It only reinforces that 'account' is an email or username, which the schema already states.

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 action 'Search', the resource 'all data breaches', and the specific subject 'a specific account (email or username)'. This distinguishes it from sibling tools like breachList and breachGet by focusing on account-centric search.

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?

The description specifies the intended use case ('Search all data breaches for a specific account') and notes the HIBP_API_KEY prerequisite. It does not explicitly mention alternatives or exclusions, but the use case is clear enough.

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

Deploy Server