Toggle light/dark mode

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

With no annotations, the description carries the full burden. It discloses the core effect (appearance changes to dark or light) but does not mention whether the setting persists across launches, affects all apps on the simulator, or requires a running simulator. Minimal transparency is present, but richer behavioral context is absent.

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 a single declarative sentence with no filler. It front-loads the action and includes the acceptable values, making it maximally efficient.

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 tool with one enum-only parameter, no output schema, and no annotations, the description covers the essential calling contract: what it does and what the parameter accepts. It omits usage conditions and persistence info, but the tool is simple enough that the included information is close to sufficient.

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 0%, so the description must compensate. The text maps the single mode parameter directly to 'dark or light,' which clarifies the semantic effect of the enum values. The main gap is that it doesn't state which value is default or how the mode relates to a system-level setting; otherwise, the parameter meaning is well conveyed.

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/resource pair — 'Set the simulator appearance to dark or light' — which clearly conveys the tool's purpose. None of the sibling tools address appearance, so it is immediately distinguishable without opening the schema.

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 offers no guidance on when to use this tool versus alternatives, no prerequisites (e.g., a booted simulator), and no exclusionary conditions. There are no sibling tools that compete directly, but the description doesn't mention that it applies only to a running simulator or that it overrides the user's settings.

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