Update characteristic color

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

With no annotations, the description carries the full transparency burden. It discloses that the operation recolors an existing value rather than creating a new one, which is a key behavioral trait. This provides meaningful context beyond the basic action and addresses the primary behavioral nuance for this operation.

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?

Two concise sentences: the first states the action and clarifies the non-creational nature; the second states required fields. No fluff, front-loaded.

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 update operation, the description covers the purpose, prerequisite, and parameter requirements. Since no output schema is present, the lack of return-value information is acceptable, but it could mention response behavior for full completeness.

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 description adds the constraint that the value must already exist, which is not in the schema, and confirms both fields are required. The schema already provides detailed descriptions with examples and special color values, so the description complements rather than repeats, earning a score above baseline.

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 the tool sets the hex code of a color characteristic value, using the specific verb 'Set' and resource 'color characteristic value'. It explicitly distinguishes from creation by noting it recolors an existing value, which differentiates it from potentially related tools like list_characteristic_colors or create tools.

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 instructs that the value must already exist and references list_characteristic_colors as a way to find such values. It also states this endpoint does not create a value, providing an explicit exclusion for when not to use it. It further notes both fields are required, covering prerequisites.

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