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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds a small amount of context by noting the result set is the covered regulations/registers with their check_ids, but says nothing about ordering, completeness, or how the live registers relate to the regulations.

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 compact sentences, with the resource description front-loaded and the filter note trailing. No filler, though the phrase 'live registers the checks cover' is slightly compressed and could be clearer.

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?

With no output schema, the description partially compensates by indicating items carry check_ids, but it does not describe the overall return shape (list? grouped by regulation?) or whether the market filter narrows regulations, registers, or both. Adequate but leaves an agent guessing at the response structure.

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 single market parameter already documents its allowed values (us, eu, uk) in the schema. The description's 'Optional market filter' merely restates that, adding no format or defaulting detail 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 the resource ('regulations and live registers the checks cover') and its payload shape ('each with its check_ids'), which is enough for an agent to distinguish it from search_checks or describe_check. It omits an explicit verb, relying on the title's 'List', but the read-only listing intent is unambiguous.

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 statement of when to reach for this tool versus siblings like search_checks or describe_check. The only usage cue is 'Optional market filter', which is a parameter note rather than routing guidance.

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