outline_cel

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

Describes the outline effect on adjacent transparent pixels and parameter 'include_diagonals', but fails to disclose whether operation is destructive, creates a new cel, or side effects like layer visibility or irreversibility.

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?

Relatively concise with a separate Args section; could be more integrated but no redundant information.

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?

Given no annotations or output schema, description lacks information about whether the cel is replaced or modified, and any side effects or prerequisites, making it incomplete for confident use.

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?

With 0% schema coverage, description adds meaning by explaining each parameter's purpose, default, and effect (e.g., 'include_diagonals: Also outline diagonal neighbors'). Explanations are clear but minimal for some parameters.

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?

Clearly states the tool adds a 1px outline around opaque pixels, with specific description of adjacent transparent pixel handling. Does not explicitly differentiate from sibling 'outline_native', but purpose is unambiguous.

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?

Provides a use case ('great for making sprites read clearly against any background') but lacks guidance on when not to use or alternatives like 'outline_native'.

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