Skip to main content
Glama
KyaniteLabs

kinocut

by KyaniteLabs
OverviewSchemaSourceRelated ServersDiscussionsAdmin
Python
Local

Change video speed

video_speed
Destructive

Change a video's playback speed to create slow-motion or fast-forward effects; the source file stays unchanged and a new video is rendered.

Instructions

Render a new video with playback speed changed; the source video is left unchanged. Returns JSON {success, output_path}. Use for slow-motion or fast-forward effects. Pass input_path as the source video and factor as the multiplier (below 1.0 slows, above 1.0 speeds up).

Input Schema

NameRequiredDescriptionDefault
factorNoPlayback speed multiplier. 2.0 is double speed, 0.5 is half speed, and 1.0 is unchanged.
overwriteNoExplicitly allow replacing existing media. Existing non-media files are protected.
input_pathYesAbsolute path to an existing local video file. The input file is read only.
output_pathNoDestination video path. Auto-generated when omitted; an existing supplied path may be overwritten.

Output Schema

NameRequiredDescriptionDefault

No arguments

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed1 schema field changedv1.16.4
    • addedInput schema / properties / overwrite
      Added value: +{
+  "default": false,
+  "description": "Explicitly allow replacing existing media. Existing non-media files are protected.",
+  "title": "Overwrite",
+  "type": "boolean"
+}
  2. Changed1 schema field changedv1.16.0
    • addedInput schema / additionalProperties
      Added value: +false
  3. Changed3 schema fields changedv1.5.1
    • addedInput schema / properties / factor / description
      Added value: +"Playback speed multiplier. 2.0 is double speed, 0.5 is half speed, and 1.0 is unchanged."
    • addedInput schema / properties / input_path / description
      Added value: +"Absolute path to an existing local video file. The input file is read only."
    • addedInput schema / properties / output_path / description
      Added value: +"Destination video path. Auto-generated when omitted; an existing supplied path may be overwritten."
  4. First observedv0.2.0

TDQS

A4.1/5.0
Behavior4/5

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

The annotations already declare readOnlyHint=false, destructiveHint=true, idempotentHint=false, and openWorldHint=false. The description adds useful behavioral context beyond that: it creates a new output file, leaves the source video unchanged, and returns JSON with success/output_path, though it does not discuss overwrite behavior or permissions.

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 short, front-loaded with the core action and result, and every sentence contributes useful information. The return format is mentioned briefly without bloating the definition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the rich input schema, existing output schema, and annotations covering safety and mutation profile, the description is complete enough. It supplies the key mental model: a new video is rendered, the source is untouched, and the factor controls slowdown or speedup.

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 100%, and the factor parameter already documents 2.0 as double speed, 0.5 as half speed, and 1.0 as unchanged. The description restates input_path as the source and clarifies above/below 1.0 behavior, but adds little meaning beyond the schema, so the baseline 3 is appropriate.

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?

The description states a specific verb and resource: rendering a new video with changed playback speed, while explicitly noting the source video is unchanged. It also frames the intended effect as slow-motion or fast-forward, but does not explicitly distinguish itself from siblings such as video_reverse or video_convert.

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?

It gives clear usage context by saying to use it for slow-motion or fast-forward effects. However, it does not name alternatives or state when not to use this tool, so routing versus other video-edit siblings is left implicit.

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

Deploy Server

Other Tools