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

Annotations already declare readOnlyHint/openWorldHint/destructiveHint=false, so the safety profile is covered. The description adds genuinely non-structured context: the precise result fields and the per-page billing rate ($0.006), which is cost behavior an agent should know before setting pages. It does not describe rate limits or result ordering.

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 tight sentences: purpose and return payload first, then the sibling disambiguation, then cost. Every sentence earns its place with no filler.

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?

There is no output schema, but the description compensates by enumerating the returned fields, and it discloses the cost implication of the pages parameter. Nothing an agent needs to invoke this correctly is missing for a two-parameter paginated search.

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%, so both 'query' and 'pages' are already documented with limits (max 500 chars, 1-10 pages, default 1). The description adds no syntax, format, or operator guidance beyond the schema, so baseline 3 applies.

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 verb+resource ('Search TikTok users by keyword') and enumerates the exact fields returned, so the agent knows precisely what it gets without opening a schema. It also distinguishes itself from the sibling tiktok_user_profile, which is a different scope (single full profile).

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?

Explicitly routes the agent: use this for keyword discovery and 'tiktok_user_profile for one account's full profile.' That is a clear alternative with a selection condition. It stops short of naming exclusions for the sibling search_tiktok (video search), but the usage context is unambiguous.

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