add_spline

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

No annotations are provided, so the description must disclose behavioral traits. It mentions the spline 'passes through or near' control points but does not state prerequisites (e.g., active sketch), side effects (e.g., sketch modification), or whether the operation is destructive. This is insufficient transparency.

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: a clear first sentence stating the action, and a second sentence providing use-case context. No redundant or irrelevant information.

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 the tool's complexity (nested objects, one parameter) and the presence of an output schema, the description covers purpose and usage adequately. It implicitly requires a current sketch but does not explicitly state prerequisites. Overall, reasonable completeness.

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 100% with a description for the 'points' parameter. The tool's description adds that the spline 'passes through or near' the points, which provides additional behavioral meaning beyond the schema's 'List of spline control points with x, y coordinates.' Baseline 3 is appropriate with minor improvement.

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 'Add a spline curve to the current sketch' with a specific verb and resource. It distinguishes splines from other sketch tools (e.g., add_line, add_circle) by highlighting free-form curves for organic shapes, which is unique among siblings.

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?

The description provides clear context by stating splines are 'ideal for creating organic shapes, complex profiles, and smooth transitions.' However, it lacks explicit when-not-to-use guidance or direct comparison with alternative tools like add_line or add_arc.

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