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

Annotations are absent, so the description alone must disclose behavior. It says only that a record 'is', not what the call does, whether it is read-only, what it returns, or that all provided parameters are ignored or discarded. No contradictions with annotations exist, but there is essentially no behavioral disclosure.

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?

At seven words the description is compact, but it is under-specified rather than efficiently complete. Every word is a noun phrase with no actionable guidance, so the brevity costs more value than it saves.

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 tool with 9 optional parameters, no output schema, no annotations, and many siblings, this description gives no information about return value, side effects, expected usage, or irrelevant parameters. It is far from complete enough for an agent to invoke it correctly.

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 input schema already documents all 9 parameters with descriptions and 100% coverage, so the baseline is 3 even without parameter info in the tool description. The description adds nothing about how parameters relate to the ISO record, but it does not need to repeat the schema.

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 identifies the subject (ISO 3166-1 record for TK) but states no verb or action, so it is unclear whether this tool returns, validates, or updates the record. It does not distinguish the tool from siblings like domain-shape or validate-json. At best it is a vague label rather than a functional description.

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 guidance about when to call this tool, what conditions make it appropriate, or which sibling tool should be used instead. The one-sentence description provides no context for selection among the many similar-looking validation and hint tools.

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