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

Annotations only declare readOnlyHint=false and openWorldHint=true; the description adds nothing — no indication of what the ranking is ranked by, whether data is live or cached, auth/quota needs, or result ordering. For a 14-parameter open-world data query the description carries no behavioral disclosure at all.

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?

It is short with no filler, but the brevity comes from omission rather than economy — a four-word label repeated from the title. Under-specification should not be rewarded as conciseness.

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 14 optional parameters, nested sortField objects, no output schema, and minimal annotations, the description supplies nothing an agent needs: not the ranking metric, not default behavior with zero required params, not the return shape. It is inadequate for this tool's complexity.

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% and every one of the 14 properties is documented inline (region, dateRange, sortField, revenue_range, etc.), so the schema does the heavy lifting. The description adds no meaning beyond it, which is the baseline 3 case.

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 a verbatim restatement of the title and tool name: 'TikTok Intelligence KD: video/rank API.' It hints that the resource is TikTok video ranking data but never states a concrete verb or what is actually retrieved, and it does nothing to distinguish it from siblings like nexscope_tiktok_video_rank, nexscope_data_kd_creator_rank, or nexscope_data_kd_video_detail.

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 when-to-use, when-not-to-use, or alternative is named. With several near-identical ranking/detail siblings (data_kd_video_detail, tiktok_video_rank, data_et_list_video_rank), an agent has no basis for choosing this one.

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