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shell_exec

Execute shell commands inside a Kali Linux container for penetration testing. Configure timeouts and raw output mode for direct results.

Instructions

Purpose: Execute a non-interactive shell command inside the Kali container. Constraints: raw=True disables semantic compaction but retains safety bounds and artifacts. This is non-interactive; use shell_exec_background or ncat/listeners for long-running jobs. Example: shell_exec(command='id && pwd')

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": {
      "command": "<command>"
    },
    "name": "shell_exec"
  }
}

Input Schema

Name	Required	Description	Default
`raw`	No
`command`	Yes
`timeout`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 8, 2026

TDQS

A4.4/5.0

Behavior4/5

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

With no annotations provided, the description carries the full burden. It discloses non-interactivity, mentions 'safety bounds', and explains raw=True's effect. However, 'safety bounds' is vague and it doesn't mention potential destructive outcomes or permissions, but the safety profile is partially addressed.

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 compact with labeled sections (Purpose, Constraints, Example). Every sentence adds value, and the example is illustrative without unnecessary verbosity.

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 tool is generic shell execution with high potential risk. The description covers purpose, non-interactive behavior, safety constraints, and alternatives. It omits timeout semantics, but the presence of an output schema reduces the need to explain return values. Overall, it is sufficiently complete for an agent to use it 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 description coverage is 0%, so the description must compensate. It explains `raw` in detail and gives an example for `command`, but does not explain `timeout`. This is incomplete for a tool with three parameters and no schema descriptions.

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 'Execute a non-interactive shell command inside the Kali container' – a specific verb and resource. It also distinguishes itself from shell_exec_background explicitly, making the purpose unambiguous.

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

Usage Guidelines5/5

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

It provides direct usage guidance: 'use shell_exec_background or ncat/listeners for long-running jobs' and explains when not to use this tool. This clearly tells the agent when to choose this tool versus alternatives.

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