PentestMCP

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get_john_formats

Check available John the Ripper hash formats to identify compatible cracking methods before starting password recovery processes.

Instructions

check available john format before cracking a hash

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "get_john_formats"
  }
}

Input Schema

Name	Required	Description	Default
No arguments

Implementation Reference

src/pentestmcp/server.py:255-257 (handler)
The handler function for the 'get_john_formats' tool. It executes the command 'john --list=formats' using the run_command helper to list available hash formats supported by John the Ripper.
```
async def get_john_formats():
    
    return run_command(["john","--list=formats"])
```
src/pentestmcp/server.py:254-254 (registration)
Registration of the 'get_john_formats' tool using the MCP decorator, specifying its name and description.
```
@mcp.tool(name="get_john_formats",description="check available john format before cracking a hash")
```

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Dec 28, 2025

TDQS

C2.9/5.0

Behavior2/5

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'check' which implies a read-only operation, but doesn't clarify if this requires specific permissions, what the output looks like, or any side effects. For a tool with zero annotation coverage, this leaves significant behavioral gaps unaddressed.

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, efficient sentence that directly states the tool's purpose without unnecessary words. It's appropriately sized for a simple tool and front-loads the essential information, making every word earn its place.

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

Completeness2/5

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

Given the complexity of security/hash-cracking tools, no annotations, and no output schema, the description is incomplete. It doesn't explain what 'john format' means, what the return value contains, or how this integrates with the sibling 'john_the_ripper' tool. For a tool in this domain, more context about formats and usage would be expected.

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

Parameters4/5

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

The tool has 0 parameters with 100% schema description coverage, so the schema fully documents the absence of inputs. The description appropriately doesn't add parameter information beyond what's already covered, maintaining focus on the tool's purpose. This meets the baseline expectation for parameterless tools.

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

Purpose3/5

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

The description states the tool's purpose ('check available john format before cracking a hash'), which is clear but vague. It specifies the action ('check') and context ('before cracking a hash'), but doesn't clarify what 'john format' refers to or how this differs from the sibling tool 'john_the_ripper'. It avoids tautology but lacks specificity for full differentiation.

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 provides minimal guidance by implying usage 'before cracking a hash', but doesn't specify when to use this tool versus alternatives like 'john_the_ripper' or other hash-related tools. No explicit when-not-to-use or prerequisite information is given, leaving the agent with insufficient context for optimal tool selection.

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