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

Annotations already provide readOnlyHint, destructiveHint false, idempotentHint. Description adds that it is free and no auth, and lists return fields. No contradictions, but the description does not add substantial behavioral insight beyond annotations.

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 sentences: first states the core action and what data is returned, second adds scale and cost context. No redundant words, front-loaded with key 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?

Given the presence of an output schema (not shown but noted), the description does not need to detail return format. It covers the tool's purpose, scope, and behavioral annotations adequately. Simple tool with sufficient documentation.

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 coverage is 100% for the 'name' parameter. The description reiterates that the tool searches by name but adds no new parameter details. It does list the data fields returned, which gives additional context to the parameter's effect.

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 the tool searches for a country by name and lists the data fields returned (population, area, capital, etc.). It uniquely identifies the tool's purpose among many siblings, none of which are country search tools.

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 context such as '250+ countries', 'No auth, free', implying it's the go-to tool for country information. However, it does not explicitly state when not to use it or mention alternatives, but given no direct sibling, it is adequate.

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