sw_planar_surface

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

The annotations declare readOnlyHint=false and destructiveHint=false, so we already know it mutates without being destructive. The description adds the requirement for a closed sketch profile, which is useful behavioral context, but it says nothing about what happens to the source sketch, whether an error is raised for open profiles, or that the result is a new feature in the active document.

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?

One short sentence, front-loaded, with zero filler. It is efficient, though the parenthetical could be slightly more explicit about its purpose.

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?

This is a mutation tool with no output schema and only nominal annotation coverage. An agent still lacks the sketch reference format, the behavior on non-closed diagrams, and the safety/reversibility picture; for a feature-creating tool, the definition is too thin.

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 67%: `doc` and `name` are documented in the schema, but `sketch` is not. The description compensates partially by stating the sketch must be closed and planar, but it does not say whether `sketch` is a feature name, a sketch ID, or an entity selector, so the agent must infer the format.

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 names a specific resource ('flat planar surface bounded by a closed sketch') and the operation is clear from context. It hints at the downstream operation of sw_thicken, but does not explicitly distinguish itself from siblings such as sw_extrude or other surface-generating tools.

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 says nothing about when to use this tool rather than sw_extrude, sw_revolve or sw_thicken. The parenthetical '(thicken it into a plate)' hints at a later step but is not phrased as routing guidance or a condition that selects one tool over another.

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