plasticity_thicken_faces

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

Beyond the annotations, it discloses that the original body is preserved, that the operation creates a new independent body, and the directional semantics of front vs back thickness relative to each face normal. The post-success instruction to re-read topology is valuable behavioral guidance. A mild tension exists with destructiveHint=true, but creating a new body while preserving the source is not an outright contradiction.

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?

Three sentences, front-loaded with the core action, followed by the preservation guarantee, geometric semantics, and the constraint. Dense and mostly waste-free, though the directionality and constraint could be tightened into one sentence.

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 5-parameter mutation tool with no output schema and no schema descriptions, the definition covers the operation, side effects on the source body, geometric direction, validity constraint, and follow-up workflow. The remaining gap is the unexplained 'intent' and 'revision' parameters, which an agent must infer.

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?

With 0% schema description coverage, the description must carry the load, and it does for the critical parameters: frontMm/backMm are nonnegative millimeters, one side must be positive, and front/back are defined relative to face normals. It omits meaning for 'intent' and 'revision' (the latter only implied by the re-read guidance), so it is strong but not fully compensating.

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 operation (copy exact current faces into a new independent native body), the source entities (Solid or Sheet faces), and the resulting artifact. This clearly distinguishes it from neighbors like plasticity_thicken_sheets, plasticity_offset_faces, and plasticity_hollow_faces, which modify or shell existing geometry rather than producing a new body from copied faces.

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 a precondition ('at least one side must be positive') and a post-run workflow ('Re-read all topology and identify the new bodies after success'), which gives useful invocation context. However, it never says when to choose this over alternatives such as plasticity_thicken_sheets or plasticity_extrude_faces, so the routing guidance is only implied.

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