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

Annotations already declare readOnlyHint=true, and the description confirms 'Does not modify the project.' It adds value by describing the file's content (design rules) and the two output formats (compact vs. extended), which is useful behavioral context beyond the annotations. 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?

The description is two sentences, front-loaded with the core action and resource, followed by usage context and a safety note. Every sentence earns its place with no fluff, and the structure is scannable.

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 read-only tool with three simple parameters, no output schema, and annotations covering safety, the description fully covers when to use it, what it returns, and the format distinctions. No missing information an agent would need to invoke it correctly.

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 already provides 100% coverage with descriptions for all three parameters. The description adds a small clarification for the 'format' parameter (compact fits a system prompt, extended is the repo file), which helps but does not significantly enhance the schema-provided semantics. Baseline 3 applies given high schema coverage.

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 states a specific verb ('Return'), a precise resource ('the Cronus UI visual taste file (DESIGN.md)'), and the key parameter space ('for a theme × look'). It clearly distinguishes itself from sibling tools by focusing on design context rather than components, install commands, or catalog entries.

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 explicitly instructs to use this tool 'before generating UI' and lists the design rules it enforces (Aurora/Neutral dual identity, one primary CTA, hairline elevation, look rules). It does not mention when not to use it or alternative tools, but the usage context is unambiguous for an agent generating UI.

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