Add a rectangle to the active document

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

With no annotations, the description must disclose side effects and requirements. It mentions 'active layer' and 'active document' but does not warn about errors if no document is open, whether the operation modifies the existing document (though implied), or what happens if invalid coordinates are provided. No return value or error behavior is described.

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 two sentences with no unnecessary words. The primary action is front-loaded in the first sentence, and the coordinate system clarification is in the second. It is efficient and easily parsed.

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?

The tool has 6 parameters, no output schema, and no annotations, so the description must carry more context. It omits error handling, prerequisites (e.g., having an active document open), and return values. An agent might not know how to interpret failures or what the tool returns upon success, which is a significant gap for a tool with multiple parameters.

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 33% (only fillColor and strokeColor have descriptions). The description clarifies that x and y coordinates are measured in points from the top-left of the artboard, which adds meaning for those parameters. However, it does not explicitly state that width and height are also in points, and it does not elaborate on the fill/stroke behavior beyond what the schema already provides. This partial compensation is helpful but not comprehensive.

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 action ('Draws a filled/stroked rectangle') with a clear resource (rectangle) and context ('active layer of the active document'). It clearly differentiates from sibling tools like `illustrator_add_ellipse` by naming the shape explicitly. The coordinate system note also adds specificity.

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 guidance is given on when to use this tool versus alternatives. The description implies it's for rectangles but does not mention conditions, prerequisites, or mention sibling tools. An agent must infer that this is the right choice for rectangle creation based solely on the name and brief description.

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