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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuine value beyond that by disclosing the concrete artifact each target yields (shadcn install command, Liquid theme files, W3C tokens document, slide files plus a render script that writes PNGs) — notably the side-effecting render script, which the annotations do not imply.

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?

Front-loaded with the core purpose, then a dense enumeration where each target clause earns its place by mapping an enum value to an artifact. It is long but nearly waste-free; the only flaw is that two clauses describe targets the schema does not accept.

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?

Output schema, rich annotations and 100% schema coverage mean return values and safety need not be re-explained, and the description covers targets and the component-narrowing case. But it omits projectId/designSystemId semantics entirely and, more seriously, promises mobile targets the schema forbids, so it is not fully coherent for a 5-parameter tool.

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%, so the baseline would be 3, but the description actively contradicts the schema: it advertises 'react-native' and 'swiftui' targets that are absent from the target enum, and says 'component' narrows 'the React install' while the schema's component parameter is scoped to inspecting source code. This makes the description misleading about valid parameter values.

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?

States a specific verb and resource ('Returns the build kit for a catalog design system or a generated project') and immediately distinguishes itself from siblings like preview-design-system and extract-design-system by enumerating exactly what each target produces. An agent can pick this tool without opening any schema.

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?

Gives per-target selection conditions ('react' for any host with filesystem + terminal, 'html' only for inline chat canvases), which is real when-to-use guidance rather than restating the name. However it offers no explicit when-NOT-to-use or alternative-tool routing (e.g. vs preview-design-system), and the enum mismatch below undercuts the guidance for mobile targets.

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