r-vid

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

With no annotations, the description carries the burden of behavioral disclosure. It discloses server-side access requirements, provider/model fallback logic, and advises max_tokens to avoid truncation—information well beyond the schema. It does not enumerate failure modes, but the key behavioral traits are covered.

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 front-loaded with a clear one-line purpose, followed by a terse, scannable parameter list. Each line adds distinct information with no repetition or filler.

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?

The description adequately covers purpose, all parameter semantics, defaults, and the output format, which is enough for a straightforward vision-model tool. It lacks explicit alternative routing and edge-case behavior, but these are not critical for a correct invocation.

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 0%, so the parameter explanations in the description are essential. It provides meaningful context for all five parameters: required direct link, default question, provider/model fallback chain, and max_tokens recommendation. This fully compensates for the empty schema property descriptions.

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 ('解析') and resource ('视频直链'), and specifies the output type ('返回文本描述或问答结果'). The video focus clearly distinguishes it from sibling image tools like r-pic, even without an explicit comparison.

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 explains how the tool works and covers parameter behavior, but it does not explicitly state when to use r-vid versus alternatives. The video-specific wording implies the usage context, yet no exclusions or alternative routing are provided.

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