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

With no annotations, the description must carry the full burden of behavioral disclosure. It only mentions a billing cost of 1 credit but does not describe pagination behavior (beyond schema hints), error scenarios, rate limits, or any side effects. The schema covers count and cursor partially, but the description adds minimal transparency.

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 concise, consisting of a single sentence plus two additional clauses. It front-loads the primary purpose immediately. The extra info about group and billing is minor but not redundant. It is not bloated, though its brevity sacrifices substance.

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 tool with 4 parameters, no output schema, and no annotations, the description is severely incomplete. It provides only a one-line purpose and does not explain return values, pagination, required fields, or any behavioral expectations. The schema offers partial parameter descriptions but the overall context is lacking.

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 description provides no parameter explanation beyond what the schema already contains. Since schema coverage is only 50%, the description should compensate for undocumented parameters like video_id and comment_id, but it does not. The parameters are somewhat self-explanatory, but 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 clearly states the tool fetches a reply list using a comment ID, which is a specific verb+resource+identifier. It is not a tautology and matches the title. However, it does not explicitly differentiate from sibling tools like get_commentList, though the name implies it is for replies to a comment.

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?

No guidance is provided on when to use this tool versus alternatives such as get_commentList. There is no mention of prerequisites (e.g., needing a valid comment_id), exclusions, or context for when this tool is appropriate.

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