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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered. The description adds content-scope context (what vocabulary is decoded) but no behavioral detail such as caching, latency, or result completeness beyond the structured fields.

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, front-loaded with the purpose and followed by the practical name_contains use case. Dense but every clause maps to a covered topic or usage instruction; no filler.

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?

An output schema exists so return-value detail is unnecessary, and the description covers the topic space and the code-conversion use case. Adequate for a reference-lookup tool, though it could note whether results are static or refreshed.

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 100%, and the nested enum descriptions already document each topic exhaustively. The description echoes the topic list and mentions name_contains' role, adding only a light usage hint over what the schema provides, so baseline 3 applies.

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 verb ('Decode') and resource ('the vocabulary the unhcr_* tools take as input'), then enumerates exactly what it returns: countries/codes, regional bureaus, dataset year coverage, population types, and asylum codes. This clearly distinguishes it from the data-returning siblings like unhcr_get_population or unhcr_get_asylum_applications.

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?

Gives a concrete usage path: 'Filter countries with name_contains to turn a country name into the ISO3 code that origin and asylum take,' which tells the agent why it would call this before other tools. It stops short of explicitly stating when NOT to use it or naming a sibling as an alternative.

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