design_set_pattern_region

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

No annotations are provided, so the description carries the full disclosure burden. It says nothing about whether an existing region is replaced, whether the layer must be a pattern layer, what errors occur for an unknown layerId, or how the clipped region affects subsequent pattern drawing.

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 tight sentences with the core action front-loaded and the supported region types as supporting detail. No filler, though the second sentence duplicates schema content.

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?

Two required parameters with a nested object are adequately covered by the schema, and no output schema exists to explain. However, for an unannotated mutation tool it omits replace-vs-add semantics and layer preconditions that an agent would need.

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% and the region parameter already contains concrete examples for all four region types, so the description's enumeration largely restates the schema. It adds no additional semantics about layerId or region validity beyond what's structured.

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 ('Set the clip region for a pattern layer') and enumerates the four supported region shapes, so an agent knows exactly what operation this performs. It doesn't name a sibling such as design_tile_region or design_set_mask to distinguish itself, so it stops short of 5.

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?

No guidance on when to use this versus the closely-related design_tile_region, design_tile_pattern, or design_set_mask, nor any prerequisite (e.g. the layer must already be a pattern layer). The agent must infer applicability from the name alone.

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