ae_addMask

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

Annotations already declare readOnlyHint=false, destructiveHint=false, openWorldHint=false, so the agent knows this mutates but does not destroy. The description adds useful detail on mode/feather/expansion/opacity/inverted options and that coordinates are in layer space, but omits what is returned (mask index?), ordering behavior, and whether existing masks are affected.

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?

A single dense sentence with the resource and shape formats front-loaded and no wasted phrasing. The em-dash run-on is efficient but slightly reduces readability, keeping it just below top marks.

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 an 11-parameter mutation tool with no output schema, the description covers the main visible fields but leaves gaps around return value, defaults for mode/opacity/feather, and the mask naming/ordering behavior. Annotations carry the safety profile, so the omission is moderate rather than severe.

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 only 27%, so the description must compensate, and it does cover the semantic core: rect/ellipse [x,y,w,h], path points in layer space, and the mask modifier fields. However, feather/expansion/opacity/inverted are merely listed without units or ranges, and 'name', 'layer' (name vs index), and 'compositionName' are left to the 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+resource ('add a mask to a layer') and enumerates the supported shape forms with coordinate conventions, which makes it distinguishable from siblings like ae_addShapeLayer or ae_addEffect. It stops short of explicitly naming an alternative sibling it is not, so it lands at 4 rather than 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?

Usage is only implied by the description of what shapes/modes are available; there is no explicit when-to-use, when-not, or named alternative. An agent can infer 'call this to add a mask' but gets no routing guidance versus related AE tools.

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