plasticity_align_planar_faces

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

Annotations already declare destructiveHint=true and readOnlyHint=false, but the description adds meaningful behavioral context: the rotation is the shortest normal-to-normal rotation, in-plane edges are not independently aligned, all moving bodies preserve relative placement, and the operation occupies one native Undo step.

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?

Every sentence is front-loaded and informative, moving from the core action to relation semantics, gap measurement, rotation caveat, and undo behavior with no filler or repetition.

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 complex mutation tool with no output schema, the description covers the alignment behavior, relation modes, rotation limitation, and undo semantics well. It is slightly incomplete on the roles of ids, revision, and intent, but an agent can still invoke the tool correctly.

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 and 7 parameters, the description must carry the burden. It defines 'relation' (opposed/same) and 'gapMm' ('measured from the target along its outward normal') and implies sourceFace/targetFace, but leaves ids, revision, and intent undocumented.

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 verb and resource: 'Rigidly rotate and move current bodies' so a source planar face aligns with a target planar face. It distinguishes itself from sibling alignment tools (align_cylindrical_faces, align_vertices, align_linear_edges) by naming the exact face-pair behavior.

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 explains the two relation modes ('opposed' seats outward normals against each other, 'same' keeps them parallel), which implies usage, but it never explicitly states when to use this tool versus alternatives like move, rotate, or align_vertices, nor any when-not condition.

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