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

With no annotations, the description carries the behavioral burden well: it discloses credit cost (3, or 13 for hashtag), that cost applies whether cached or not, and that failures are refunded. It does not describe permission requirements or the shape of returned data, but the cost/refund disclosure is genuinely useful context beyond the schema.

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, front-loaded with the core purpose before result modes and usage. Every sentence carries distinct information with no redundancy.

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 five-parameter tool with no output schema, the description covers purpose, result modes, usage context, and cost behavior; pagination semantics are handled by the cursor and limit schema descriptions. It is nearly complete, missing only a note on how results are ordered or returned.

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, but the description adds real semantic value by mapping `type` values to their returned resources (user→accounts, hashtag→hashtags) and by tying a cost differential to that enum. It leaves `fresh`, `limit`, and `cursor` to the schema, which documents them adequately.

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 by keyword) and immediately clarifies the three result modes the single endpoint can produce. It separates itself from the surrounding get_tiktok_* tools by scoping its purpose to discovery when the target is unknown.

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 says to use it for trend research and creator discovery 'when you do not already have a username,' which implicitly routes the agent to profile/listing tools when an identifier is known. It does not name a sibling or an exclusion by name, so it falls just short of a 5.

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