System List Settings Domains

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

The annotations already indicate readOnlyHint and idempotentHint, so the safe, read-only nature is covered. The description adds no behavioral context such as what a 'settings domain' is, whether enumeration is local, or how results are scoped. It does not contradict the annotations, but it provides no additional transparency value.

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 single sentence is short, but it is empty filler that simply repeats the tool name. Under-specification is not conciseness, and the sentence does not earn its place in the definition.

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?

Despite having zero parameters and an output schema, the description fails to clarify what 'settings domains' are or how this tool relates to sibling preference and settings tools. The agent is left to infer semantics from the name alone, which is risky for discoverability. The output schema may define the return shape, but it cannot explain when or why to invoke this tool.

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 tool has zero parameters, so the schema fully covers the calling contract. The absence of parameter information in the description is acceptable because there is nothing to document.

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 restates the tool name verbatim and only adds the unhelpful framing 'Delegated Apple domain tool...'. It never explicitly states that the tool lists available settings domains, so an agent must infer the function from the name alone. This is closer to a tautology than a purpose statement.

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?

No guidance is provided on when to call this tool instead of related siblings such as system_read_preference_domain, system_get_settings_snapshot, or apple_get_preferences. There is no context about expected use cases or exclusions, so an agent has no basis for selecting among alternatives. The description is neutral but unhelpful.

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