ai_add_rectangle

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

With no annotations, the description carries the behavioral burden. It discloses that x/y are bottom-left coordinates in points and that fill RGB is optional, defaulting to no fill. It does not mention return value or effects on selection/layers, but for a simple non-destructive add operation the key call-time behavior is stated.

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?

A single sentence front-loads the action and scope, then packs all seven parameters into a compact mapping with the optional fill behavior. Every clause earns its place; no filler or redundant restatement of the schema.

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 7-parameter shape-creation tool with no annotations or output schema, the description plus the rich input schema covers the rectangle geometry, units, and fill defaults. Gaps such as required-parameter clarification and behavior when no active document exists are minor and inferable from '当前 Illustrator 文档'.

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 100%, so the baseline is 3. The description restates the existing parameter meanings and adds minimal grouping ('fr/fg/fb' as optional RGB fill, no fill if absent), but it does not clarify whether x/y/w/h are effectively required despite schema declaring zero required 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?

The description opens with '在当前 Illustrator 文档中画一个矩形' — a specific verb ('画'), resource ('矩形'), and scope ('当前 Illustrator 文档'). This clearly differentiates the tool from sibling add-shape tools such as ai_add_ellipse and ai_add_text.

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?

Use is implied by the shape and app context: choose this when adding a rectangle to the active Illustrator document. However, it does not explicitly state when to prefer it over ai_add_ellipse/ai_add_polygon or mention prerequisites/error conditions, so the guidance is only implicit.

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