desaturate

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

With no annotations, the description carries the full burden and does disclose the default target (active layer), per-parameter defaults, and that a status dict is returned. It omits whether the pixel change is destructive/undoable, whether it applies only to the layer or to any selection, and how missing layers are reported.

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?

One-line purpose followed by a compact parameter list; front-loaded and free of filler. The mode default is restated in both the description and the schema, a minor redundancy, but nothing 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?

For a three-parameter pixel-mutation tool, the description covers purpose, every parameter, defaults, and the return type. The main gap is the absence of any note about destructiveness or undo, which matters most for a tool with no annotations and no output schema.

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 0%, so the description must compensate, and it does enumerate the mode values (luminosity, luma, average, lightness) plus defaults for all three parameters — real value the schema lacks. However it never explains what image_index indexes (multiple open images) or how layer_name is matched when duplicated, so the compensation is partial.

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: "Convert a layer to grayscale (desaturate)", which is unambiguous. It does not distinguish itself from convert_color_mode, a sibling that also produces grayscale output via a different mechanism, so it falls short of full sibling differentiation.

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 when-to-use or when-not-to-use guidance is given, and no alternatives are named. An agent cannot tell from this text whether to use desaturate or convert_color_mode for a grayscale result, nor what preconditions (an open image, an existing layer) apply.

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