material.create_node_group

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

Annotations are all false (readOnlyHint=false, openWorldHint=false, idempotentHint=false, destructiveHint=false), so the description carries the burden of explaining behavior. It only states 'Risk: standard; maturity: L3' and that checks apply, which are generic harness facts, not tool-specific behavior. It does not disclose what the command does to the material, whether it modifies the node tree, whether it is reversible, or what side effects occur.

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 short but not informative. It front-loads the command name and generic risk/maturity metadata, which is not useful for invocation. The sentence 'Requirements: Per-request argument checks and session policy still apply' is boilerplate that applies to all tools and does not earn its place.

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 tool with 8 parameters, no idempotency, no read-only guarantee, and no open-world guarantee, the description is severely incomplete. It does not explain the operation, the effect on the material, the required scene state, or how the output schema relates to the created node group. The output schema exists but the description gives no context for interpreting 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 only 38%, and the description adds no parameter meaning. The schema shows groupName, material, baseColor, roughness, and several underscore-prefixed harness fields, but the description does not explain how baseColor/roughness relate to the node group, what format material expects, or what groupName should be. The description fails to compensate for the low 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 is essentially a label: 'PartMe Blender Harness command `material.create_node_group`.' It restates the tool name and title without stating what the tool does, what a node group is, or what creating one accomplishes. It does not distinguish this from sibling tools like blender_geometry_nodes_create_group or blender_material_create_pbr.

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?

The description provides no guidance on when to use this tool versus alternatives. It only mentions generic 'Per-request argument checks and session policy still apply,' which is not usage direction. An agent cannot tell whether to use this for creating a reusable material node group versus other material or geometry node group tools.

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