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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds the return shape ('side-by-side rows'), which is modest but real value; it says nothing about row limits, ordering, or what happens when a country lacks data for a topic.

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?

A single front-loaded sentence with an inline example; no filler, no restatement of the title. Every clause carries information.

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?

There is no output schema, so the description must carry the return-value burden, and 'side-by-side rows' is only a partial picture — no mention of what fields appear per row, ordering, or handling of missing data. For a low-complexity two-parameter tool this is adequate but thin.

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?

Schema description coverage is 0%, so the description must compensate, and the example does illustrate both arguments concretely (a topic value plus three country values). However, it never clarifies the expected country format (name vs. ISO code) and relies on the schema's enum for valid topic values.

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+resource: produce side-by-side rows comparing several countries on a single topic, with a concrete example. It is distinguishable from single-country siblings like get_country_profile by implication ('several countries'), but never names an alternative tool explicitly.

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?

Usage is only implied through the example ('tax_systems for Panama, Paraguay and Uruguay') and the word 'several'. There is no statement of when to prefer this over get_country_profile or list_countries, and no exclusions or prerequisites.

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