fill_layer

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

No annotations provided; the description carries full disclosure burden. It does not specify whether the fill overwrites existing content, only affects the current cel, or if it is reversible. For a tool that modifies pixel data, this is insufficient.

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?

While the single sentence is concise, it omits critical information needed for correct use. The brevity sacrifices clarity, making it under-specified rather than efficiently informative.

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 no output schema, no annotations, and a description that fails to explain even required parameters, the tool definition is severely incomplete. An AI agent lacks sufficient context to invoke this tool correctly or interpret its behavior.

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?

The input schema has 0% description coverage on properties. The description adds no details beyond mentioning 'solid colour,' leaving the meaning and format of 'color,' 'filename,' 'frame,' and 'layer' entirely unspecified.

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 action (fill), the resource (entire target layer/frame cel), and the method (solid colour). This distinguishes it from sibling tools like fill_area, fill_checkerboard, or fill_gradient that fill only portions or patterns.

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 explicit guidance on when to use this tool versus alternatives like fill_area or fill_gradient. The description implies it is for entire layer fills but does not mention prerequisites, such as requiring an existing layer or the need to specify a valid filename.

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