get_video_info

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description does add genuinely useful interpretation context beyond annotations — that comment counts include second-level replies, danmaku counts and full duration are summed across all parts, while segment duration is per-segment — but it says nothing about auth needs, rate limits, or failure behavior.

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 text is short and the statistical caveats are valuable, but it is not front-loaded with a purpose statement — it opens with a field enumeration that duplicates what the existing output schema already provides, making the first sentence the weakest rather than the strongest part.

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?

With an output schema present, the description need not restate return fields, and it does supply the non-obvious aggregation semantics an agent needs to interpret those fields correctly. Annotations cover the safety profile and the schema covers both parameters, leaving only usage routing unaddressed.

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 both url (link/short-link/BV-av/share text) and page (1-based segment index, fallback to ?p=N, then segment 1) are already fully documented in the schema. The description contributes nothing additional about parameters, so the baseline 3 applies.

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 never states an action verb; it opens with a list of returned fields (title, author, publish time, description, statistics), which largely restates the tool name get_video_info. It weakly implies the resource is a single video's metadata rather than comments/danmaku/parts, but the differentiation from siblings is left to inference.

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?

There is no statement of when to use this tool, no prerequisites, and no reference to alternatives such as get_parts or get_comments even though those siblings overlap in subject matter. The agent must infer usage purely from the name and schema.

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