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

Annotations already establish readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety is covered. The description contributes the shape of the return (IDs per geographic level) and the direct-code shortcut, but says nothing about match behavior (exact vs fuzzy), result limits, or what happens when a name resolves to nothing — useful context for a lookup tool over an external taxonomy.

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?

Two sentences, front-loaded with the core action, and zero filler. The country-code caveat is appended as a distinct, scannable sentence rather than buried mid-thought.

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?

With five parameters, one required, 80% schema coverage and no output schema, the description needs to carry purpose, return shape and usage context — it does all three and even adds the direct-code escape hatch. It stops short of describing result granularity (does a query return IDs at every level simultaneously?) or any pagination, which is the only meaningful gap.

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 already 80%, so the schema documents folder, account, country and language. The description still adds real meaning: "by name" clarifies what the undocumented required query parameter accepts, and the country-code list clarifies the accepted value format for country beyond the schema's single "e.g. SA" example.

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 pairs a specific verb ("Find") with a specific resource ("TikTok location IDs") and enumerates the geographic levels it resolves (country, region/province, city), plus the reason for doing so ("for targeting"). It reads clearly as the TikTok counterpart to google_ads_find_locations / meta_targeting_search, but it never explicitly contrasts itself with those siblings, leaving platform disambiguation to the tool name alone.

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 frames the use case (resolve names to IDs when building targeting) and adds a genuine short-circuit: for the fourteen listed countries, the code can be passed directly instead of searching. That is an implicit when-NOT-to-use. It doesn't state the converse condition, e.g. that regions and cities must go through this tool, or that unknown names need a fallback.

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