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

Annotations already mark the tool as read-only, idempotent, and non-destructive. The description goes further by disclosing paging behavior: it returns every match unless limit/offset is supplied, applies a default/cap, stops early for long results, and reports nextOffset. This is useful behavioral context beyond the 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 compact and front-loaded: the purpose is stated in the first clause, followed by concise paging behavior. Every sentence contributes meaningful information without filler or redundancy.

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 a full output schema, complete parameter descriptions, and strong annotations, the description provides the remaining context an agent needs: what the resource is, what fields are returned, and how paging behaves. Nothing essential 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?

The schema already documents all four parameters with 100% coverage, including defaults, maximums, and enum values. The description repeats the limit default/cap and adds the 'returns every match unless limit or offset is supplied' paging nuance, but that is largely additional framing rather than new parameter semantics.

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 states a specific verb and resource: 'List the insurance supervisory authority for every covered country,' and enumerates the included fields (name, acronym, website, currency, notes, register source). This clearly distinguishes it from sibling tools like list_insurers and list_groups, which target different entities.

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 clearly conveys when to use the tool: when you need insurance regulators across covered countries, optionally paged or filtered by region/continent. It does not explicitly name alternatives or exclusions, but the context is strong enough that an agent can select it appropriately against the sibling list.

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