add_node_group_instance

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

No annotations are provided, so the description carries full responsibility for behavioral disclosure. It only states the basic operation without revealing side effects, failure modes, or requirements. For example, it does not say what happens if the material is invalid or the node group does not exist.

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?

The description is a single sentence with no filler, making it concise. However, its brevity comes at the expense of necessary detail, so it is not optimally calibrated for the tool's complexity.

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 three parameters, no annotations, and an output schema that is not shown, the description is incomplete. It lacks parameter semantics, behavioral context, and any mention of return values or side effects. The tool has enough complexity to require a richer description.

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 0%, and the description provides no explanation of the parameters. It does not clarify what 'location' represents, nor the format expected for material or group_name. The schema itself lacks descriptions, so the description offers no compensation.

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 clearly states the action (Add), the object (instance of an existing node group), and the target (material). It distinguishes from siblings like create_node_group which creates a new group, and create_shader_node which adds a generic shader node.

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 explicit guidance on when to use this tool versus alternatives. It does not mention prerequisites, such as the material or node group needing to exist, nor does it reference any sibling tools. The only implicit usage is inferred from the name and description.

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