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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds little beyond confirming that a list of locations is returned, with no rate-limit, auth, or format context.

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, but 'by this API call' is filler and the filtering sentence adds ambiguity rather than value. Front-loaded enough but not every sentence earns its place.

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 an output schema present, return values need no explanation, and a zero-parameter list tool is simple. Still, the description does not clarify that this is the YouTube-specific location set or how the 'filter by country' remark relates to a parameterless call, leaving a small 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?

The tool takes no parameters, so the baseline is 4. The description's mention of 'filter by country' does not correspond to any parameter here and reads as stray context rather than parameter documentation.

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 name and title identify this as the YouTube SERP locations list, but the description itself only says 'You will receive the list of locations by this API call', which is vague about the resource being YouTube-specific. It is distinguishable from the sibling get_dataforseo_serp_youtube_languages mainly via the tool name, not the prose.

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?

The only guidance is 'You can filter the list of locations by country when setting a task', which is confusing given the tool accepts zero parameters and cannot perform any filtering itself. It implies the filter is applied elsewhere but never says when to call this tool versus the languages sibling.

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