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vm_input

Control mouse and keyboard input in a VM guest to move, click, drag, scroll, press keys, and type text; verify effects with vm_observe.

Instructions

Mouse/keyboard action in a guest. Actions: move, click, drag, scroll, press, type_text, key_down/up, mouse_down/up, release_all. Verify effect with vm_observe.

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": {
      "session": "<session>",
      "owner_thread_id": "<owner_thread_id>",
      "capture_id": "<capture_id>",
      "action": "<action>"
    },
    "name": "vm_input"
  }
}

Input Schema

Name	Required	Description	Default
`args`	No
`action`	Yes
`session`	Yes
`capture_id`	Yes
`owner_thread_id`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.4.0Nov 5, 2026

TDQS

C2.9/5.0

Behavior2/5

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

No annotations are supplied, so the description carries the full behavioral burden. It discloses the action vocabulary, but says nothing about side effects in the guest, irreversibility of input, or that failing actions may leave partial state; only verification is hinted at.

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?

Two compact sentences, front-loaded with the capability and the action list, with the verification hint last. No filler; arguably too terse given the parameter opacity, but well structured.

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?

A five-parameter, four-required mutation tool with no annotations, no output schema, and no schema descriptions needs substantially more: the per-action shape of 'args' and the meaning of the session/thread/capture identifiers are absent, so an agent cannot confidently construct a correct call.

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% across five parameters. The description only gives meaning to 'action' (which the schema leaves as an unconstrained string) and is silent on 'args', 'session', 'capture_id', and 'owner_thread_id' — the four required inputs an agent must supply correctly.

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?

States the resource and domain clearly ('Mouse/keyboard action in a guest') and enumerates the concrete action set, which distinguishes it from siblings like vm_exec (code execution) and vm_observe (read-only inspection). It lacks a single crisp verb but the enumeration substitutes well.

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 closing sentence routes the agent to vm_observe for verification, which is useful guidance. However, there is no statement of preconditions (e.g., that a capture_id from observation is required) or when input should be avoided in favor of vm_exec or higher-level tools.

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