outline_cel

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

Describes key behavioral traits: adds outline, fills adjacent transparent pixels, effect of include_diagonals. Lacks explicit mention of destructiveness (modifies file in place), but behavior is clear. No annotation contradictions.

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?

Well-structured with a summary, behavior explanation, and Args list. Each sentence adds value; no wasted words. Concise yet 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?

Adequately covers behavior and parameters. No output schema, but return value is implicit (modification). Could mention that it modifies the sprite in place, but sufficient for a modification tool.

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%, so description must compensate. It fully explains each parameter: filename, layer_name, frame_index, color (default black), include_diagonals (default False, thickens outline). Adds meaning beyond schema types and defaults.

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 it adds a 1px outline around opaque pixels of a cel, using specific verb+resource. Distinguishes from sibling 'outline_native' by describing the algorithm (outline around opaque pixels, filling adjacent transparent pixels).

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?

Implies usage with 'Great for making sprites read clearly against any background', but does not explicitly state when not to use or compare to 'outline_native'. No exclusions or alternatives are provided.

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