NCA control families

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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so the safety profile is covered. The description adds the shape of what is returned (families, applicability, baseline) but says nothing about ordering, completeness, or how baseline status relates to the entities involved.

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?

A single sentence with no filler, and the resource is front-loaded ahead of the purpose clause. Nothing is wasted, though it is arguably compressed enough to lose some detail.

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 zero-required-parameter read-only listing with no output schema, the description adequately conveys what is returned and why. It could say more about the relationship between families and the baseline concept, but nothing essential to a correct call 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% and both parameters carry enum descriptions, so the schema fully documents lang and response_format. The description adds no parameter-level information, which is the expected baseline when the schema does the heavy lifting.

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?

Specific verb+resource: 'List the NCA control families', and it names the attributes returned (applicability, baseline). It does not explicitly differentiate itself from siblings like ecc_list_domains or ecc_overview, so an agent must infer the distinction from names alone.

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 trailing clause 'to help decide which NCA controls apply to an entity' implies the usage context but states no explicit when-to-use, prerequisites, or alternatives to compare against. An agent gets a hint, not a routing rule.

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