Read or adjust display brightness

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

No annotations are provided, so the description carries the burden. It discloses the post-action reporting of the measured value, which is useful. However, it does not mention any side effects (e.g., permanent changes to brightness, OSD behavior, or persistence) or dependencies like permission requirements.

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 concise sentence that front-loads the main action and adds the reporting detail. No 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?

The description mentions reporting a measured value, but since there is no output schema, it should clarify what that value is (e.g., brightness percentage) and any error conditions. More importantly, it completely omits explanation of the 'change' parameter, leaving agents unable to correctly invoke the adjustment portion. Completeness is inadequate for the tool's dual read/adjust capability.

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 input schema has a single 'change' parameter with zero description coverage (0%), and the tool description does not explain what this parameter means or how to use it. Agents cannot infer from the description whether 'change' expects absolute values, deltas, or the enum strings 'off'/'on'. This is a critical gap.

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?

Description states specific verb ('Read or adjust') and resource ('brightness on the focused display'), and clarifies it reports the measured value afterwards. Clearly distinguishes from siblings like keyboard_backlight by naming 'display' and its action.

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?

Provides context that the tool acts on the focused display, but does not explicitly state when to use it versus alternatives (e.g., read-only vs. adjustment scenarios, or when keyboard_backlight should be used instead). No exclusions or conditions are given.

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