set_skeletal_mesh_material_slot

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

Annotations already declare destructive=true, idempotent=true, and readOnly=false, so the safety profile is covered. The description adds useful behavior beyond that: it writes FSkeletalMaterial.MaterialInterface, requires an existing slot, and never auto-grows the array, plus it documents the return shape despite no output schema.

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-loaded with the action and scope, followed by two concise constraints and a compact return summary. Every part earns its place and nothing is wasted.

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 4-parameter mutation tool with full schema coverage and annotations, the description is nearly complete: it explains the write target, slot addressing, non-growth, and return fields. It could still clarify save semantics and failure behavior when a slot is missing, but no critical invocation detail is absent.

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 explains each parameter, including the slot_name/slot_index mutual exclusivity and the content-path parameters. The description reinforces 'exactly one' and 'existing', but adds little parameter meaning beyond what the schema already provides, so the baseline 3 is appropriate.

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 ('Assign a material to an existing material slot of a skeletal mesh ASSET') and even names the underlying write target. The 'skeletal mesh ASSET' phrasing distinguishes it from sibling static-mesh or read-only slot 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?

Gives clear usage constraints: address the slot by slot_index OR slot_name (exactly one) and never auto-grows the slot array. It does not explicitly name alternatives like get_skeletal_mesh_material_slots for reading or set_static_mesh_material_slot for static meshes, so it stops short of full when/when-not guidance.

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