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

With no annotations provided, the description must carry the burden of disclosing behavior. It only states billing per call, which is a minor detail, but fails to mention pagination behavior, whether calls are read-only, or any side effects. The phrasing 'Video Related Contents Group' suggests a grouping but is unhelpful.

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 extremely short, which could be concise, but it is under-specified rather than concise. It lacks structure and fails to provide any useful information. The sentence 'Video Related Contents Group: Video. Billing per call: 1 Credits.' is wasteful because it repeats the title and provides billing info that might belong elsewhere.

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?

Given 4 parameters, 0 required, no output schema, and no annotations, the description is completely inadequate. For a tool with multiple parameters and no other structured metadata, it must explain its purpose, parameters, and expected behavior. This description provides none of that.

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 description must compensate, but it does not mention any parameters. It does not explain the meaning of 'gl', 'hl', 'id', or 'cursor' beyond what the schema properties provide; the schema already has titles for 'id' and 'cursor'. The description adds no semantic value.

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 is nearly a tautology, repeating the title 'Video Related Contents' without specifying what kind of related contents (e.g., similar videos, suggestions) or how they are selected. It does not hint at a verb or action beyond the obvious 'get', and provides no differentiation from siblings like get_v1_video_comments or get_v2_video_details.

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 guidance on when to use this tool versus alternatives. The description only mentions billing, which is not usage guidance. An agent cannot infer whether this is for recommendations, related links, or other content, nor when to prefer it over sibling tools.

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