invert_colors

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

Without annotations, the description bears the full burden of behavioral disclosure. It only notes that alpha is preserved, but fails to clarify if the operation is destructive, whether it modifies the sprite in-place, or what happens when parameters like layer or frame are not specified. The agent cannot fully anticipate side effects.

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?

The description is a single 10-word sentence that efficiently conveys the core purpose. Every word earns its place, with no redundancy or filler.

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 tool with 3 parameters (1 required) and no output schema, the description lacks essential context: what 'filename' represents, default behaviors for frame and layer, and what the tool returns or confirms. Without annotations, significant information is missing.

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%, but the description does not explain any of the three parameters (filename, frame, layer). The agent needs to infer what 'filename' refers to, what 'null' means for layer, and how 'frame' is used. This is a critical gap.

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 clearly states the tool's function: 'Invert the RGB colours of a layer's pixels (alpha preserved).' This specifies a unique action (invert) on a specific resource (layer's pixels) and distinguishes it from sibling tools like 'desaturate' or 'replace_color'.

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 guidance is provided on when to use this tool versus alternatives. There is no mention of prerequisites, when not to use it, or context where other tools might be preferred. The description only states what it does, leaving the agent to infer usage.

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