silhouette_render_preview

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

Annotations already declare destructiveHint=false and idempotentHint=true, and the description usefully discloses the return payload (PNG path, pixel dimensions, warnings). However, readOnlyHint=false signals a side effect — writing a file — and the description never says where the PNG is written, whether an existing file is overwritten, or how the filename argument interacts with that, which is the key behavioral gap.

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 core action and finished with the return contract. No filler or redundant restatement of the tool name.

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 correctly covers return values, and it explains the preview's visual content. It remains incomplete on file-write behavior, dpi effects, and whether rendering mutates the design, which matter for a non-read-only tool with three undocumented parameters.

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 0%, so the description must carry the burden for all three parameters, and it says nothing about 'design', 'dpi', or 'filename'. The details it does give (10 mm grid, safety margin, pixel dimensions) are not parameters at all, so it adds no meaning over the bare schema.

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: 'Render a colour-coded PNG preview of the design', plus the notable rendering details (10 mm grid, safety margin). An agent can distinguish it from shape-editing siblings, but no sibling is named and it doesn't clarify how it differs from export or open-in-studio workflows.

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?

'For visual inspection before cutting' gives a clear phase-of-work context for when to call it. There are no explicit when-not conditions or named alternatives, so it stops short of full routing guidance.

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