add_modifier

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

With no annotations, the description carries the behavioral burden and does disclose meaningful traits: z coordinates are measured from the object's bottom, region coordinates from the center, negative removes material, modifier changes settings inside, and cylinder shape derives width from the smaller region side. It does not cover permissions, reversibility, or return behavior, but it provides substantial operational context.

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 dense but front-loaded with the core action, then organized by kind and shape. It contains no obvious filler, though the single-paragraph run-on format could be slightly easier to scan.

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 tool with no schema descriptions, no annotations, and no output schema, the description is complete enough to support correct invocation. It covers the key geometric semantics and kind behavior; missing details are mainly around the object parameter and any return/undo behavior.

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 0%, so the description must compensate, and it largely does: it explains z_from/z_to origins and the z_to=0 top convention, region format [x0, y0, x1, y1] from center, kind values, shape values including cylinder width semantics, and a settings example. Only the object parameter is not elaborated, but its meaning is evident from the first sentence.

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 and resource: adding a part to an object, with kinds modifier, negative, support_blocker, and support_enforcer. It is clear what the tool does, but it does not explicitly differentiate itself from sibling tools such as add_shape or add_relief.

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 gives implied usage through kind explanations and examples, such as using negative for a magnet hole and modifier for changing infill in a region. However, it does not explicitly say when to use this tool versus alternatives or name any sibling tools, so guidance remains inferential.

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