setLayerMask

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

With no annotations, the description carries the full behavioral burden. It signals a mutation ('Create or modify') and lists changeable attributes, but says nothing about what happens on create vs. modify, whether an existing mask is overwritten, permission/auth needs, or error conditions for an 11-parameter 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?

A single front-loaded sentence with the purpose first and the attribute list second; it is compact and readable. The parenthetical enumeration is somewhat redundant against the schema, 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, zero-required, nested-object mutation tool with no annotations and no output schema, the description omits far too much: which parameters are needed to create vs. modify, how masks are identified (name vs. index), and how it relates to addLayerMask. The definition is inadequate for the tool's complexity.

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 100%, so the schema already documents every parameter and the baseline is 3. The description's parenthetical field list (shape vertices, mode, feather, opacity, expansion, inverted) merely restates a subset of parameter names without adding units, defaults, or interaction rules.

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 ('Create or modify layer masks') and enumerates the attributes it touches, so the agent knows what the tool operates on. However, it does not distinguish itself from the sibling addLayerMask, and 'Create or modify' actively overlaps with that sibling's apparent purpose, leaving the boundary unclear.

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?

There is no when-to-use guidance, no prerequisites (e.g. that a comp and layer must already exist), and no mention of the alternative addLayerMask. Given the sibling overlap, the absence of routing guidance is a real gap.

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