plane_cut_fracture

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

Annotations already declare destructiveHint=true, readOnlyHint=false, idempotentHint=false, so the safety profile is covered. The description adds real value beyond that: it discloses that the asset is saved at the end, that islands are split by default, that no noise is applied, and the precise failure conditions (no new pieces or save failure). Missing details on permissions/undo, but strong for an annotated tool.

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?

Front-loads the core action, then failure semantics, then the return shape. Every sentence carries information about behavior the schema cannot express. The returns block is dense but earns its place given there is no output schema. Slightly long, but 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?

With no output schema, the description compensates by spelling out the returned fields (geometry_collection_path, num_planes, new_fracture_count, transform_count, success, saved, save_error). Combined with the schema's full parameter coverage and the annotation safety profile, an agent has what it needs to call this correctly; the only gap is the absence of sibling routing.

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 description coverage is 100%, so the schema already documents grout, num_planes, random_seed, split_islands and the path. The description reinforces num_planes semantics ('the transforms the cut added') and island splitting, but adds little about grout or random_seed. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

States a specific verb and resource: 'Cuts all transforms of a UGeometryCollection asset with num_planes random planes inside its bounds'. The operation is well-scoped (random planes, within bounds, no noise), which helps distinguish it from the nearby fracture/slice family. However, it never names or contrasts with siblings like fracture_geometry_collection or slice_fracture, leaving the agent to infer which cutting tool applies.

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?

Usage is implied by the operation described (cutting a collection with random planes), and failure conditions ('empty collection, or planes that miss every piece') hint at when it will not work. But there is no explicit when-to-use or when-not-to-use guidance and no routing to the alternative cutting tools (fracture_geometry_collection, slice_fracture), which is what an agent choosing among them most needs.

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