tool_get_country_facts

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

With no annotations, the description must carry the behavioral burden. It discloses the upstream data source (RestCountries, live) and implicitly that this is a read-only lookup, but says nothing about caching, rate limits, latency, or what happens with an unrecognized country name.

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?

Front-loaded with the resource and its fields, followed by a compact Args block. Slightly over-structured for a single parameter, but no wasted sentences.

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?

With no output schema and no annotations, the description's enumeration of returned fields effectively documents the response shape, which is the key gap it needed to fill. Missing only edge-case behavior for invalid country inputs.

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%, yet the description fully specifies the single parameter: country name or ISO 2/3-letter code, with concrete examples ('Japan', 'JP', 'JPN'). This is exactly the compensation needed for an undocumented schema parameter.

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?

States a specific resource and enumerates exactly which facts are returned (capital, languages, population, currency, timezones, calling code, borders), plus names the data source (RestCountries). It does not explicitly differentiate itself from the overlapping sibling tool_get_destination_info, so it stops short of a 5.

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?

There is no statement of when to use this tool versus alternatives like tool_get_destination_info or tool_get_cost_of_living. The only contextual cue is 'Live data from RestCountries,' which describes sourcing rather than invocation conditions.

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