Suggest a component combination

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that: it discloses the full output composition and a concrete workflow rule ('Copy the source blocks before editing; do not regenerate them'), which tells the agent how to treat the returned source.

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 sentences, front-loaded with the purpose and then the operator instruction. The artifact list is dense but every item earns its place by telling the agent what comes back.

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?

No output schema exists, so the description appropriately enumerates the return contents in lieu of one. Combined with annotations covering the safety profile and 100% schema coverage on parameters, an agent has nearly everything needed to call it correctly; only sibling routing is absent.

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 use_case, constraints and surface_type are all already documented in the schema. The description adds no syntax, format or defaulting detail beyond what the schema provides, so the baseline 3 applies.

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 transformation (use case -> design direction) and enumerates the concrete artifacts produced: palette, type pairing, wireframe, TSX scaffold, component source. That is far more than a restatement of the title. It does not, however, explicitly differentiate itself from siblings like get_design_tokens or validate_ui_composition.

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 conveys the input-to-output story but never says when to reach for this tool versus the five siblings. There is no when-not guidance and no named alternative, leaving the agent to infer the routing decision.

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