MoviePy MCP Server

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set_volume

Adjust audio volume by a scaling factor (0.5 = half, 2.0 = double, 0 = silent) for audio clips or the audio track of video clips.

Instructions

Scale volume: 0.5 = half, 2.0 = double, 0 = silent.

Works on audio clips and on the audio track of video clips.

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": {
      "clip_id": "<clip_id>",
      "factor": "<factor>"
    },
    "name": "set_volume"
  }
}

Input Schema

Name	Required	Description	Default
`factor`	Yes
`clip_id`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Aug 1, 2026

TDQS

A4.2/5.0

Behavior3/5

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

With no annotations provided, the description carries the burden of behavioral disclosure. It usefully explains factor semantics (0.5=half, 2.0=double, 0=silent) and the applicable media types, but does not disclose whether the operation mutates the original clip or returns a new one, nor any side effects or error conditions.

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 concise, with only two sentences, and is front-loaded with the most important information (the scaling examples). Every sentence adds value without redundancy.

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?

For a simple transformation tool, the description is largely complete: it explains the purpose, target media types, and parameter semantics. An output schema exists to cover return values, so the only notable gap is the lack of side-effect disclosure (mutation vs. new clip).

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?

Schema description coverage is 0%, so the description must compensate. It explicitly explains the 'factor' parameter with three concrete examples, which is highly valuable. The 'clip_id' parameter is self-explanatory from its name, but no constraints (e.g., accepted range for factor) are provided.

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 uses the specific verb 'Scale volume' and names the exact resource (audio clips and audio track of video clips). It clearly distinguishes the tool from unrelated siblings like adjust_colors or to_grayscale.

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

Usage Guidelines4/5

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

The description clearly states the context of use by specifying that it works on audio clips and video clips' audio tracks. However, it does not explicitly mention when not to use it or name any alternatives, though none are obvious among siblings.

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