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

Annotations already declare read-only, idempotent, non-destructive, closed-world, so the safety profile is free. The description adds real context beyond that: the response is a bundled multi-section payload, lint findings are precomputed/'already known', and the payload can be narrowed via include — which matters for a potentially large read. It doesn't mention payload size limits or failure behavior for bad IDs.

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: the first front-loads the payload contents, the second front-loads the usage condition and the parameter hint. No filler, and every clause carries information.

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?

With no output schema, the description carries the burden of describing return shape, and it does so by enumerating all five section types that the include enum also names. Combined with the pre-call guidance, an agent has everything needed 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?

Schema description coverage is 100% and both properties are documented, including the enum values for include. The description's note that 'include narrows the sections returned' restates the schema rather than adding format or interaction detail, 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 verb and resource plus full payload enumeration: screens, navigation flow, React + Tailwind components, self-contained HTML, and lint findings. An agent can distinguish this from generate_ui_design or list_designs 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?

'Use this before implementing a screen from a design' gives a clear triggering context, and 'replaces reading the raw HTML and guessing at the structure' explains the value relative to a manual approach. It stops short of naming sibling tools (e.g. refine_ui_design, generate_ui_design) as alternatives, so there is no explicit exclusion rule.

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