draw_rectangle

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

No annotations are present, so the description must disclose behavioral traits. It does not mention whether the operation modifies the file permanently, overwrites existing pixels, or any side effects. The description is minimal.

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 concise with a clear leading sentence and structured parameter list. No unnecessary information is included, but it could benefit from a brief usage example.

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 simple drawing tool, the description covers the basic parameters and purpose. However, it lacks details about coordinate system, clipping behavior, or post-drawing state (e.g., if the canvas is saved). With 7 parameters and no output schema, it is adequate but not complete.

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?

The description adds meaning beyond the input schema by listing constraints (e.g., width > 0, height > 0) and defaults (color, fill). Since schema description coverage is 0%, this compensates well, though parameter descriptions are still brief.

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 clearly states the action ('Draw a rectangle') and the resource ('on the canvas'). It is specific and distinguishable from most siblings, though there is a sibling 'draw_rectangle_at' which could cause confusion without further differentiation.

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 provided on when to use this tool versus alternatives like 'draw_rectangle_at' or other drawing tools. There is no mention of prerequisites or context.

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