Set light color

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

Annotations indicate readOnlyHint=false, aligning with the write nature of setting color. The description does not disclose side effects, authentication needs, or rate limits, but it adequately describes the expected behavior without contradictions.

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 concise with two sentences: the first states the purpose, the second provides key usage details. No redundant information, every sentence is essential.

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 setter tool with no output schema, the description covers parameter constraints and relationships. It does not explain return values, but that is not critical for this action. Overall complete given the tool's simplicity.

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%, baseline 3. The description adds value by explaining mutual exclusivity of color parameters, providing an example hex, and clarifying brightness and timing ranges, going beyond schema descriptions.

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 clearly states 'Set the color and brightness of the user's lights,' specifying the verb and resource. It does not explicitly differentiate from sibling tools like set_lumia_state, but the focus on lights is clear.

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 provides explicit guidance on parameter usage: 'Provide exactly one of: hex, rgb, or ct' and explains brightness, transition, and duration ranges. It does not mention when not to use this tool or suggest alternatives, but the provided context is sufficient.

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