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

With no annotations, the description carries the full burden of behavioral disclosure. It states 'conversion' and 'browser-based', but does not explain how the agent should provide the input video, what the output format is, whether upload is involved, or any limitations. This is a meaningful gap for a tool with zero parameters and no output schema.

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 two short, front-loaded segments that immediately communicate the core function. Every phrase adds value: conversion, dimensions, target platforms, and browser-based nature. No filler or redundant information.

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?

For a no-parameter tool, the description gives essential details: target output size, purpose, and platform. However, it omits the '3 modes' details, input mechanism, and any constraints or output specifics. It is adequate for a low-complexity tool but leaves notable gaps about actual usage flow.

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?

The tool has zero parameters and schema coverage is 100%, so the baseline is 4. The description mentions '3 modes' but does not explain how they are selected, which is slightly confusing given the empty input schema. However, since there are no parameters to document, the description does not need to add parameter-level details.

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 clearly states the tool converts horizontal videos to 1080x1920 vertical videos, specifying the exact output dimensions and target platforms (Shorts/Reels/TikTok). This specific verb+resource pairing distinguishes it from sibling tools like yt-captions or yt-denoise.

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?

It provides clear usage context by naming the target platforms (Shorts/Reels/TikTok) and notes it is a browser-based tool, implying it is used via a web interface rather than API calls. It does not explicitly mention alternatives or exclusions, but the context is sufficient for basic selection.

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