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

No annotations are provided, so the description carries the full burden. It discloses a meaningful behavioral trait: only the latest available value per country is used, not a time series. However, it does not describe what happens with missing data, the return structure, or other edge-case behavior, leaving some gaps.

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 two short sentences with no filler. The core behavior is front-loaded, and the second sentence adds a directly useful use case rather than redundant detail.

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?

For a simple two-parameter tool, the description is largely complete: it explains the purpose, the input focus, and the type of comparison. It does not describe the exact output format, but the phrase 'compare across countries' sufficiently implies a per-country result list or mapping.

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 input schema already provides 100% parameter coverage with detailed descriptions for countries and indicator. The description adds little parameter-specific meaning beyond reinforcing that a single indicator is compared across countries, so the baseline of 3 is appropriate.

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 uses a specific verb and resource: 'Compare one indicator across several countries.' It also adds the important qualifier 'latest available value each,' making the tool's scope precise and distinguishing it from single-country or time-series siblings like country_indicator and country_profile.

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 phrase 'Good for ranking or benchmarking economies' gives a clear use case and context for when this tool is appropriate. However, it does not explicitly state when not to use it or name alternatives such as country_indicator or us_series.

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