Retrieve football countries, optionally filtered by name substring, to support league identification and searching.
List countries (optionally filtered by name substring), for use with search_leagues.
| Name | Required | Description | Default |
|---|---|---|---|
| lang | No | Language code for team/league names, e.g. en, es, de, ja, zh-cn | |
| page | No | Page number (default 1) | |
| search | No | Country name substring |
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description does not need to restate safety behavior. It adds a small behavioral touch by noting the filter is optional and substring-based, but it does not reveal details like pagination behavior or result shape, which would add further transparency.
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 sentence that front-loads the core action ('List countries'), then states the optional filter and the intended usage context. There is no wasted wording and every clause adds useful 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?
For a simple read-only list tool with rich annotations and fully documented parameters, the description adequately explains the tool's purpose, filter behavior, and relationship to search_leagues. An output schema is absent, but for a straightforward country-listing tool the key calling context is covered; slight gaps around return format and pagination keep it from a 5.
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?
All three parameters have descriptions in the schema, so schema coverage is 100% and the schema carries the load. The description's mention of filtering by name substring adds no meaning beyond the existing 'search' parameter description, so it earns the baseline 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 says 'List countries', which is a clear verb+resource pairing, and notes the optional 'name substring' filter. It also identifies its intended role as a helper for search_leagues, which differentiates it from the other listed tools that are all about fixtures, odds, or standings.
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 'for use with search_leagues' gives clear context on when this tool is relevant: as a lookup/filtering aid before searching leagues. No alternative country-listing sibling exists among the provided tools, so explicit exclusion is unnecessary; the context is sufficient.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.