set_color

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

With no annotations, the description carries the full burden of behavioral disclosure, but it only states the basic mutation 'Set'. It does not mention side effects such as changing color mode, turning the light on, invalid hex handling, device reachability, or reversibility.

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, front-loaded sentence with no wasted words. The action is stated first, and the format examples are compact and immediately useful.

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 simple two-parameter setter with an output schema, the core call is understandable, but the description is not fully self-contained. It lacks guidance on device identifier provenance and important behavioral caveats, though the low complexity and clear color format keep it minimally viable.

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 schema only provides parameter names with no descriptions, so the description adds real value by specifying that color is a hex string and giving examples like '#FF8800' and 'f80'. It also clarifies that device refers to a light, though it doesn't explain where the device identifier comes from.

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 names the verb 'Set', the resource 'a light's colour', and the input format 'hex string'. It is immediately distinguishable from siblings like set_brightness, set_power, and set_color_temp because it is specific about color and hex encoding.

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 gives no explicit guidance on when to use this tool instead of set_color_temp, set_brightness, or set_power, and no prerequisites are mentioned. Usage is only implied by the action of setting a color, so an agent gets no direction about alternatives or exclusions.

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