design_add_building

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

With no annotations, the description carries the full burden. It usefully discloses the output character (filled silhouette shapes, intentionally low-detail) and enumerates presets, but says nothing about layer stacking, whether an existing sketch is required, reversibility, or what happens when both 'preset' and 'buildingType' are supplied.

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?

Three sentences, front-loaded with purpose and the key style caveat. Slight redundancy in restating the six preset names already present in the schema enum, but no filler prose.

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 creative layer-creation tool with zero required params and a fully described schema, the description covers what gets made and its visual character. The absence of any mention of positioning, depth lanes, or layer ordering is a modest gap given 11 optional 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 coverage is 100%, so the schema already documents all 11 parameters including enums and defaults. The description's preset list duplicates the enum rather than adding meaning, and it explains nothing about seed, xPosition/yPosition, depthLane, or the preset-vs-buildingType overlap.

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 opens with a specific verb+resource ('Add a simple architectural silhouette layer') and clarifies the rendering style ('filled shapes', 'silhouette impressions, not detailed architecture'). That framing separates it from the detailed-architecture siblings like design_set_building_style, though no sibling is named explicitly.

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?

Usage is only implied — an agent infers this belongs in a landscape/scene composition step. The 'not detailed architecture' note is a soft exclusion, but there is no explicit when-to-use, when-not-to-use, or pointer to alternatives such as design_add_shape or design_set_building_style.

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