blender_create_primitive

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

The annotations are all false and provide no behavioral context, so the description carries the burden. It adds useful non-obvious behavior: units are meters, rotation is Euler radians, dimensions define final physical size and override scale for meshes, and the light object applies only to point_light. It does not mention possible name conflicts or return values, but it gives more than a minimal viability threshold.

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?

Three short sentences front-load the purpose and then pack in the non-obvious constraints. Every sentence earns its place, and there is no redundant restating of schema facts.

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 10-parameter creation tool with no output schema, the description plus the input schema cover the core create action, units, and a key scale-vs-dimensions behavior. Gaps remain: what happens on duplicate names, what collection/display_size/semantic_type mean, and what the tool returns after creation. These may be partially self-evident, but not fully specified.

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 coverage is around 50%, so the description must compensate for missing parameter explanations. It does add semantics for dimensions/scale precedence and the light/point_light dependency, and reinforces units. However, several parameters such as collection, display_size, semantic_type, and the primitive enum values are left unexplained in both schema and description, so compensation is incomplete.

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 the specific action and resource: 'Create one allowlisted Blender primitive.' This clearly identifies the tool as creating primitive objects and distinguishes it from sibling creation tools like blender_create_curve and blender_create_camera. The allowed-set notion mirrors the primitive enum, so an agent can tell what it is for without opening the schema.

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 statement of when to use this tool versus alternatives such as blender_set_light, blender_set_point_light, blender_create_curve, or blender_create_camera. The only condition mentioned, 'light is valid only for point_light,' is a parameter-level constraint, not guidance for tool selection. The agent has to infer usage from the tool name and sibling list.

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