set_decal_size

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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=true, idempotentHint=true), so the bar is lowered. The description adds the return signature but says nothing about what the call mutates, permission needs, or why a size setter carries destructiveHint=true. Adequate but thin given annotations already carry the load.

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?

Two tight sentences: the action is front-loaded and the return shape follows. Nothing is padded, though the return-value line borders on redundant given how minimal the operation is.

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?

No output schema exists, and the description does supply the return shape, which partially compensates. However, with a destructiveHint=true mutation and no guidance on prerequisites, reversibility, or actor-lookup failure, the definition leaves meaningful gaps for an agent invoking it.

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 all five parameters, including the decal_size override of size_x/y/z. The description only echoes the 'half-extent' concept and adds no syntax or precedence detail beyond what the schema provides, matching the baseline for full schema coverage.

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 verb and resource ('Set the DecalSize half-extent on a UDecalComponent parented under a DecalActor'), which is precise enough to separate it from decal siblings like set_decal_color or set_decal_fade. It stops short of explicitly naming those siblings or stating the scenario, but the resource and property are unambiguous.

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?

There is no when-to-use or when-not guidance, and no reference to the numerous decal siblings (set_decal_material, set_decal_sort_order, set_decal_color). The agent must infer context purely from the tool name.

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