Color

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

Annotations indicate not read-only or destructive. Description explains that setting colors and swapping modify state, while sample-pixel reads. It adds context beyond annotations by describing each action's effect. No 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?

Description is two sentences, front-loaded with purpose, then lists actions. Every sentence adds value. No 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?

For a tool with multiple actions and no output schema, description does not explain return values (e.g., sample-pixel returns a color object). This is a gap. Otherwise, it covers the core functionality adequately.

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 coverage is 100%, so baseline is 3. Description adds meaning by linking actions to required parameters (color for set-foreground/set-background, x,y for sample-pixel, none for swap). It clarifies which parameters are used when.

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 clearly states it manages foreground and background colors, and lists specific actions. This distinguishes it from sibling tools which handle layers, filters, adjustments, etc. The verb 'manages' plus resource 'colors' is specific.

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?

Description implicitly tells when to use by listing actions: set colors, swap, sample pixel. It does not explicitly state when not to use or suggest alternatives, but the context is clear. No exclusions.

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