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vm_exec

Run scripts or commands inside a VMware guest through its existing OpenSSH profile, returning stdout, stderr, and exit status for isolated host-side automation.

Instructions

Execute through the VM's existing OpenSSH profile; return guest stdout, stderr and exit status.

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": {
      "vm": "<vm>",
      "script": "<script>"
    },
    "name": "vm_exec"
  }
}

Input Schema

Name	Required	Description	Default
`vm`	Yes
`script`	Yes
`timeout`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.4.0Nov 5, 2026

TDQS

C2.9/5.0

Behavior3/5

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

With no annotations, the description carries the full burden; it does disclose the transport (existing OpenSSH profile) and the exact return surface (stdout, stderr, exit status), which is useful. It says nothing about the obvious risk of running arbitrary scripts in a guest, whether execution blocks, what happens on timeout, or whether the call can mutate guest state.

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?

A single front-loaded sentence with no filler, and the return contract is stated up front. It is arguably undersized for a three-parameter execution tool, but nothing in it is wasted.

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?

For an arbitrary-code-execution tool with zero annotations, an undocumented schema and no output schema, the definition is thin. Stating the return surface partly offsets the missing output schema, but identification of the target VM, timeout behavior and side-effect profile are all left to inference.

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

Parameters2/5

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 and it does not. It never clarifies whether "vm" is a name, ID or profile reference, what form "script" takes (shell line, multi-line, interpreter), or what the timeout parameter bounds beyond the schema default of 20.

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

Purpose4/5

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

"Execute through the VM's existing OpenSSH profile" states a specific verb (execute) and channel (guest over SSH) plus the return payload (stdout, stderr, exit status). It is clear what the tool does, but it never distinguishes itself from near siblings like vm_input, vm_connect or vm_prepare_console, so an agent still has to guess which to reach for.

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?

There is no when-to-use, when-not-to-use, or alternative-tool guidance despite a large sibling set that includes vm_input and vm_connect. The phrase "existing OpenSSH profile" hints at a prerequisite (a configured profile) but states no requirement, ordering, or exclusion.

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