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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is fully covered by structured data. The description adds only the country-filter context and says nothing about completeness of the returned list, pagination, or coverage — leaving the annotation bar unmet only marginally.

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 short sentences with the result statement front-loaded. The phrasing 'You will receive the list of locations by this API call' is slightly padded but not wasteful enough to penalize heavily.

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 zero parameters, an output schema present, and annotations covering the safety profile, the description only needs to frame what the tool provides and why. It does that adequately, though it omits the scraper/Gemini context that would make the tool's scope unambiguous.

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?

The tool takes zero parameters, so the baseline is 4; there is nothing for the description to document beyond the empty schema it supplies.

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 states a clear verb and resource: it returns a list of locations. It does not, however, distinguish this tool from close siblings such as get_dataforseo_ai_gemini_llm_scraper_languages or the various *_locales tools, so an agent must rely on the tool name to disambiguate.

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?

'You can filter the list of locations by country when setting a task' implies the downstream purpose (obtaining valid location values for task configuration), but there is no explicit when-to-use guidance, no prerequisite statement, and no routing to an alternative sibling tool.

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