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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely non-structural context: the data originates from TikTok's own Creative Center leaderboard and each call 'costs 1 credit', which is important cost/latency information an agent cannot get from the schema. It does not describe pagination behavior or result shape, keeping it below a 5.

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?

Four short, front-loaded sentences with no filler; the value/cost note is placed last where it belongs. The leading 'Popular creators.' largely repeats the title and could be merged, but it functions as a scannable headline.

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 read-only, open-world listing tool with six optional params and no output schema, the definition covers source, filters and cost. However, it never says what a creator record contains or how pagination/ordering works, and the phantom 'category' filter leaves an agent guessing which filters actually exist.

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 83%, so the schema does the heavy lifting (period windows, region codes, follower bands are all documented). The description only restates 'country' and 'follower band' while adding a 'category' filter that does not exist in the schema, and it says nothing about period, count or cursor semantics — the one extra detail it offers is potentially misleading.

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?

States a specific resource (creators) with scope ('trending in a market') and provenance (TikTok's Creative Center leaderboard), which implicitly separates it from tiktok_popularVideos, tiktok_popularSongs and tiktok_trending. No sibling is named explicitly, so the differentiation is inferred rather than stated.

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?

'Creators trending in a market' implies the discovery use case and the filter dimensions hint at narrowing by market/audience size. But there is no explicit when-to-use, no when-not-to-use, and no pointer to alternative tools such as tiktok_trending or tiktok_popularVideos for the same job.

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