set_object_ray_visibility

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

With no annotations, the description does meaningful work: it discloses the merge semantics of unset flags, that the return payload echoes every flag post-change, and a renderer-specific caveat ('shadow_catcher: Cycles only'). It does not say whether the object must exist, whether changes are undoable, or what happens on an unknown object_name, so the mutation profile is incomplete.

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?

A one-sentence summary of the capability plus a front-loaded intent statement, then a terse per-argument list where every line adds information absent from the schema. No repetition and nothing 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 nine-parameter mutation tool with no annotations, the definition is largely self-sufficient, and the output schema means return values need not be re-explained. The remaining gap is failure behavior and any permission or context requirements, which are unaddressed.

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 0%, so the description carries the full burden, and it defines every one of the nine parameters in domain terms ('diffuse: Lights matte surfaces by bounced light', 'transmission: Shows through glass'). This is exactly the compensation the low coverage requires.

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 opens with a specific verb-and-resource framing ('Choose which rays see an object') and illustrates the outcome with concrete examples (hide from camera but keep shadow, shadow catcher). It is clearly distinct in kind from generic visibility toggling, though it never names the neighboring set_object_visibility or set_shadow_settings tools that an agent might otherwise reach for.

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 supplies the intent behind each mode and gives an explicit pairing instruction ('pair with set_film transparent') as well as the crucial partial-update rule 'Leave anything unset to keep it.' It stops short of stating when not to use this versus the general visibility tool, so the routing is implied rather than spelled out.

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