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

Annotations already declare this as a read-only, idempotent, open-world, non-destructive lookup, so the safety profile is covered. The description adds useful context about source attribution and Europe-only CEE17 campsite connectors, but it does not discuss invalid country codes, missing data, or other edge behavior.

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 returned data and followed by direct usage guidance. There is no redundant or filler text.

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?

The tool has rich annotations, an output schema, and fully documented parameters; the description supplies the remaining purpose and usage context. Nothing essential for correct invocation is missing.

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%, so country_code and locale are already fully documented in the schema. The description reinforces the one-country scope but adds no parameter syntax, format, or locale behavior beyond 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 names a specific resource and scope: plug types, mains voltage/frequency for one country, the source value, and European CEE17 campsite connectors. It clearly distinguishes this lookup from unrelated sibling tools such as visa, fuel, or weather tools.

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?

It explicitly says to use this tool for socket/plug types, adapters, mains voltage, and campsite hook-ups, giving clear positive guidance. It does not state when not to use it or name alternatives, but no direct sibling overlap exists.

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