List countries supported by the combined income calculator

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

With no annotations, the description carries the full burden. It explicitly states that the tool returns data and describes what it returns, implying a read-only safe operation. It does not mention pagination, sorting, or failure modes, but for a simple list tool this is not a major gap.

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 a single, tightly written sentence that front-loads the primary action and result, followed by the use case. No redundant words or filler.

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?

No output schema is provided, so the description must explain what is returned. It does so ('country code/name') and explains the purpose. It could specify the exact return shape (e.g., array of objects) but for a simple list tool the description is sufficient.

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 baseline score is 4 per the rubric. The description adds no parameter info, but none is needed. It does clarify the output is country code/name, which helps set expectations.

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 a specific verb ('Returns') and resource ('every country code/name currency_takehome_calculator accepts'), and ties it to a concrete use case (filtering available international-account providers). It distinguishes itself from sibling tools by naming the exact calculator it serves.

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 description provides clear context for when to use the tool ('used to filter which international-account providers... are available'). It does not explicitly name alternatives or state when not to use it, but the intended workflow is obvious for a zero-parameter list tool.

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