update_mask

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

No annotations are provided, so the description carries full disclosure burden. It never states permissions needed, whether the change is undoable/reversible, how it behaves if no mask exists on the layer, or whether an empty box moves versus scales the mask — significant gaps 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?

A single front-loaded sentence with no filler, listing the four operations compactly. It is efficient, though the comma-list of verbs is dense and does not structure which parameter drives which behavior.

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 6 undocumented parameters, no annotations, and no output schema, the description is too thin for the tool's complexity. It conveys the operation types but leaves parameter meaning, preconditions, and failure behavior entirely unaddressed.

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 0% across 6 parameters, so the description must compensate. It loosely maps to invert ('invert'), density/feather ('soften', 'weaken') and box ('move'), but 'layer' and 'project' are never addressed and no value formats, ranges, or units are given for density/feather.

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 names specific operations (invert, soften, weaken, move) applied to 'an existing mask', which is a clear verb+resource statement. It implicitly contrasts with set_mask/remove_mask by scoping to modification of an existing mask, though it never names those siblings 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?

The word 'existing' implies a mask must already be present, giving implicit usage context, but there is no explicit statement of when to prefer this over set_mask, mask_stroke, or remove_mask, and no prerequisites or ordering guidance.

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