loft

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

Annotations already declare this is a non-read-only, non-destructive, closed-world creation tool, so the safety profile is covered. The description usefully adds that the output is a 'closed body', that sections must be ordered along the axis, and what 'roundness' values mean, but it never states what is returned (new object name/handle) or any post-creation behavior. With annotations carrying the safety burden, this is adequate but not rich.

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?

Front-loaded with the core action and the section format, then routing guidance. Dense but every sentence adds information; only the inline JSON example makes it slightly heavy to parse.

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 creation tool with annotations covering safety and no output schema, the description covers the non-obvious parts: section data shape, ordering, and the loft_from_masks alternative. The remaining gap is unexplained geometry controls (axis, segments, subdivisions) and no indication of the return value.

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 0% and the 'sections' items object is opaque (additionalProperties: true), so the description carries the full burden — and it does document the critical nested shape with a concrete example ({'at': [x,y,z], 'size': [w,d], 'roundness': 2}) plus the roundness scale (2=ellipse, 4=rounded box) and ordering rule. It leaves axis, caps, segments, and subdivisions unexplained, which prevents a 5.

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?

States a specific verb and resource: 'Make a closed body from cross-sections you give as numbers along an axis.' It also names the sibling it is not (loft_from_masks) and the shapes it targets, so an agent can distinguish it from array, lathe, sweep, and extrude_profile without opening schemas.

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?

Gives concrete when-to-use examples ('torsos, heads, bottles, columns') and an explicit alternative with a selecting condition: 'With a front and a side image of the form use loft_from_masks.' That is an explicit when/when-not plus alternative routing.

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