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

Annotations already mark the tool readOnly/idempotent, so the description's main contribution is pagination behavior: cursor offset, continuation via previous response, and re-ranking instability. That is genuinely useful behavioral context beyond the annotations.

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?

Three short sentences, each earning its place: what the tool returns, how pagination works, and a dedupe warning. No filler or repetition of schema details.

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?

Covers primary behavior, pagination, and a stability caveat despite no output schema. It stops short of describing the exact response shape or field names beyond comment_id, but what an agent needs to call and paginate correctly is present.

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 coverage is 100%, so the baseline is 3; the description adds meaning by explaining how cursor relates to the previous response and why comment_id should be used for deduplication. This is practical semantics not fully captured in the schema.

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 names the resource ('comments on a video') and narrows scope to 'Top-level comments' with like/reply counts, making it easy to distinguish from tiktok_comment_replies. It also defines the purpose in a single front-loaded phrase.

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?

It gives clear operational guidance: pass the previous cursor to continue and dedupe on comment_id because TikTok re-ranks between pages. It does not explicitly name sibling alternatives or exclusion conditions, though 'top-level' plus sibling tiktok_comment_replies implies the boundary.

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