swept_region

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

With no annotations, the description carries the full burden and does so well: it discloses the sampling/stepping behavior, that cutting happens off the layer faces, that the join is made margin_mm wider within tolerance_mm, and the counter-clockwise winding convention. It omits nothing critical for invocation, though it does not discuss cost, failure modes, or the exact return shape beyond 'count'.

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?

Purpose is front-loaded in the opening sentence, and the dense follow-on sentences each carry real constraint information (stepping, margins, winding, downstream use). It is a little stream-of-consciousness and could be tightened, but there is no filler.

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 an 8-parameter, no-output-schema, no-annotation geometric tool, the description supplies enough -- process, key constraints, orientation, and the count/count-of-regions hint -- for an agent to call it correctly. Return detail is light but the essential contract is covered.

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 values (the stepped joint dimension), heights_mm (a few heights inside a layer, not on faces), margin_mm, tolerance_mm, frame (component vs assembly default), and axis (the cut axis). Only dimension and component are left somewhat implicit.

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 first sentence gives a specific verb and resource -- outlining what a component sweeps in a plane as a joint moves -- which is a distinct operation. It does not explicitly contrast against near relatives like add_swept_profile or cut_profile_through_plane, so an agent must still infer the boundary, but the core purpose is unambiguous.

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?

It states the goal (to keep clear of the swept volume or cut it away) and ties the operation into a workflow, naming check_motion as the analogous stepping tool and add_sketch as the consumer of the result. No explicit when-not or alternative selection is given, so it stops short of a 5.

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