character

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

With no annotations, the description must carry the full behavioral burden. It discloses that the character is built on its own layer in a specific pass order and that x,y anchor the feet, but it does not state whether existing layer content is overwritten, whether path refers to a project or destination file, or what the call returns.

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 dense but front-loaded: the purpose and process come first, then the spec grammar, then color formats. The long enumerated spec and color lists are compact and earn their place, though the prose is somewhat terse and telegraphic.

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 a complex nested spec, no output schema, and no annotations, the description covers the creative payload well but omits critical operational semantics for path, layer, frame, and return behavior. It is adequate to start building a character but not complete enough to predict side effects or result shape.

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 only 25%, so the description must compensate. It does an excellent job documenting the complex nested 'spec' object and the x/y/scale anchoring, but leaves 'path', 'layer', and 'frame' unexplained beyond minimal schema text, leaving material gaps for a low-coverage schema.

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 states a specific verb and resource ('Build a chibi character') and gives concrete scope details (~44px at scale 1, feet at x,y, on its own layer, ordered part passes). It distinguishes itself somewhat from generic draw/create tools by describing a procedural character builder, though it doesn't name a sibling alternative.

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?

Usage is implied by the description of building a chibi character from a detailed spec, and 'Batch op: person' hints at a batch path. However, there is no explicit guidance on when to choose this tool versus create_sprite, generate, or batch, nor any exclusions or prerequisites.

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