design_update_layer

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

No annotations exist, so the description carries the full behavioral burden. It discloses that valid property keys differ by layer type, which is useful, but says nothing about permissions, whether unknown keys error or are ignored, whether the update is additive or replacing, or reversibility — all material for a mutation tool.

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 compact sentences with the general behavior first and the layer-type exception second — well front-loaded and free of filler. It could have been trimmed slightly, but no sentence is wasted.

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 and a free-form properties object, the description gives enough to attempt a call for common cases, but leaves the agent guessing on error behavior for invalid keys and on what is returned. Adequate but with real gaps for a mutation of a nested object.

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%, but the `properties` parameter is a free-form object with additionalProperties unspecified, so the schema alone tells the agent nothing about valid keys. The description compensates by enumerating example keys (text content, filter intensity, shape fill color) and the full painting:stroke key set (pathSource, pathBrushId, pathColor, depthMapping).

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 ('Update properties on a design layer') and gives concrete examples of updatable property domains (text content, filter intensity, fill color), which goes beyond the bare name. It does not explicitly contrast itself with design_set_text, design_set_shape_style, or design_set_transform, so an agent must infer the boundary.

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 implies when to use it via the property examples and the painting:stroke specialization, but never states when to prefer the dedicated setters (design_set_text, design_set_transform) over this generic path. Usage is inferable but not spelled out.

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