HALO (GEMMA-by-GOOGLE)

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run_hydra

Perform parallelized brute-force password attacks on network services like SSH and FTP using a username and password wordlist.

Instructions

Parallelized network login brute-forcer across many protocols.

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": {
      "target": "<target>",
      "username": "<username>"
    },
    "name": "run_hydra"
  }
}

Input Schema

Name	Required	Description	Default
`target`	Yes	Target host.
`service`	No	Protocol, e.g. ssh/ftp/http-get.	ssh
`threads`	No	Parallel tasks.	16
`username`	Yes	Username to test.
`wordlist`	No	Password wordlist path.	/usr/share/seclists/Passwords/Common-Credentials/darkweb2017_top-1000.txt

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Jul 10, 2026

TDQS

B3.3/5.0

Behavior2/5

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

No annotations exist, so the description carries full burden. It mentions parallelism and brute-forcing but fails to disclose potential consequences like account lockouts, network disruption, or legal implications. The description does not warn about destructive nature or authorization requirements.

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

Conciseness4/5

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

The description is a single efficient sentence with no waste. However, for a sensitive tool, it could benefit from additional context without being overly long. Still, it is front-loaded and clear.

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 tool's complexity (5 parameters, no output schema, no annotations) and sensitivity, the description is incomplete. It does not explain return values, success/failure behavior, or safety considerations. Sibling tools are similar but no differentiation is provided.

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 descriptions for each parameter already exist. The tool description adds no parameter-specific meaning beyond the general statement. Baseline 3 is appropriate as schema already documents parameters well.

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 it's a 'parallelized network login brute-forcer across many protocols,' specifying the verb (brute-force), resource (network login), and scope. This distinguishes it from sibling tools like run_ncrack or run_medusa which target specific protocols or are general crackers.

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

Usage Guidelines3/5

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

The description implies usage for brute-forcing network logins but does not provide explicit guidance on when to use this tool over alternatives or any prerequisites. No exclusions or context are given for selecting protocols or handling potential lockout risks.

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