list_countriesLists 76 countries with ISO code, currency, example salary, and statutory employer cost. Filter by region to compare hiring costs.
Countries covered (76), with ISO code, currency, example salary and the statutory employer cost at that salary. Data snapshot 2026-10-01. Cost comparison, not legal or tax advice.
| Name | Required | Description | Default |
|---|---|---|---|
| region | No | Filter by region, e.g. "Europe", "Asia", "Latin America" |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuine context beyond that: the dataset vintage ('Data snapshot 2026-10-01'), the catalog size (76), the fields each entry carries, and an explicit scope limitation. It still says nothing about pagination or how entries are ordered, but this is a solid addition over the structured hints.
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?
Three compact sentences with no filler: scope and fields first, then snapshot date, then the disclaimer. Front-loaded and appropriately sized for a read-only catalog tool.
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, the description usefully names the returned fields (ISO code, currency, example salary, statutory employer cost), which compensates for the missing return spec. The only real gap is that filtering by region is never acknowledged, but for a one-optional-param read-only list this is close to complete.
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 single optional 'region' parameter is fully documented in the schema (100% coverage, with examples), so the schema does the heavy lifting. The description never mentions filtering, but per calibration a high-coverage schema sets the baseline at 3.
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 the scope ('Countries covered (76)') and enumerates the returned fields, so the agent can infer it is a catalog of supported countries. However, it never states the action as a verb+resource (e.g. 'List the countries supported...'), leaving the purpose to be read off the name/title. No explicit differentiation from compare_countries, which is the nearest sibling.
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 when-to-use guidance, no prerequisites, and no routing to alternatives such as compare_countries for actual comparisons. The only usage-adjacent content is the disclaimer 'Cost comparison, not legal or tax advice', which limits liability rather than guiding selection.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.