serp_list_countries

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

No annotations are provided, but the description honestly states that the tool returns a table of country codes, implying a read-only operation. It is straightforward and does not hide any behavioral traits.

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?

The description is three sentences, front-loads the purpose, and includes a return description. Every sentence is relevant and concise.

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?

Given no parameters and an output schema, the description is largely complete. It could mention the output format or that it lists only 'common' codes, but overall it suffices for the simple tool.

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 has zero parameters, so the description cannot add meaning beyond the schema. Per guidelines, this is a baseline of 4.

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 clearly states verb ('list'/'shows') and resource ('country codes for Google search'), and it is distinct from sibling tools that list other types (languages, search types, time ranges).

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?

While the purpose is clear, the description provides no explicit guidance on when to use this tool over its siblings or when not to use it. The usage context is only implicit.

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