Add a fade-in, fade-out, or both to a video. Provide the video path and set durations in seconds to create fade transitions at the beginning or end.
Add a fade-in and/or fade-out to a video (seconds).
| Name | Required | Description | Default |
|---|---|---|---|
| fade_in | No | Fade-in duration in seconds | |
| fade_out | No | Fade-out duration in seconds | |
| video_path | Yes | Local path to the video |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden of disclosing behavior. It only says fades are added and gives units; it does not state whether the original file is modified in place, whether a new file is produced, or how existing fades are handled.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single sentence with no filler, front-loading the verb and object. The parenthetical '(seconds)' compactly communicates the required units.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Parameter coverage is complete and the operation is conceptually simple, but the description omits output or destination behavior, which matters more because there is no output schema and no annotations. It is adequate for basic selection but not fully self-contained for an agent wanting to predict the mutation's result.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents video_path, fade_in, and fade_out. The description adds the 'and/or' relationship and seconds unit but does not provide meaning beyond what the schema already contains.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb ('Add'), a specific resource ('a video'), and the exact effect ('fade-in and/or fade-out'), with units in seconds. This clearly distinguishes it from sibling video tools like trim_video or add_watermark.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies the tool should be used when applying fades, but it does not explicitly say when to prefer it over alternatives or mention any exclusions or prerequisites. Usage is inferable from the name and action, but no direct guidance is provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.