bilibili-video-downloader

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

With no annotations, the description carries the full burden and does disclose the key behavior: download and return a video address. It does not mention limitations such as public availability, authentication, membership-only videos, or the exact form of the returned address, so disclosure is only minimally adequate.

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?

A single front-loaded sentence with no filler. It states action, input, and output in compact Chinese, so every part earns its place.

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 one-parameter, no-output-schema downloader, the description is nearly sufficient: it names input and return value. It still lacks a note about accepted URL variants or error conditions, but these are minor for this complexity.

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 percent and the schema already documents the url parameter with an example. The description only restates the idea of a video link, adding no new semantic detail beyond the schema. Baseline 3 is appropriate.

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 and resource: it downloads Bilibili videos from a video link and returns the video address. This clearly distinguishes it from platform-specific sibling downloaders such as youtube-video-downloader or tiktok-video-downloader.

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 tool's purpose implies use when the user provides a direct Bilibili video URL, and the sibling names make platform selection easy. However, it never explicitly states when to prefer this over related Bilibili tools like bilibili-search-download or what URL forms are unsupported.

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