uis_list_countries

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint. The description adds that it returns ISO codes and provides examples, plus the Args/Returns section. No contradictions, and it adds useful context 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?

The description is concise, front-loads the main purpose, includes examples, and is well-structured with paragraphs and an Args/Returns block. No unnecessary 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 and low tool complexity, the description provides sufficient context: purpose, return format, examples, and types of regions. It is complete for agent usage.

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 schema already contains descriptions for both parameters (search and entity_type). The description briefly repeats them in the Args section but does not add significant new meaning. Schema description coverage is 0% according to signal, but actual schema descriptions exist, so the description adds minimal value.

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's purpose: listing available countries and regions from UNESCO UIS database, returning ISO codes. It distinguishes from sibling tools like uis_compare_countries and uis_get_education_data by focusing on the list of regions.

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 explains that the tool is used to obtain ISO codes for data queries and lists various region types. It does not explicitly state when not to use, but the context is clear and sufficient.

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