set_mesh_surface_material

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the core action without revealing side effects: does it modify the .tscn file permanently, overwrite existing materials, or require the scene to be loaded? This is insufficient for a mutating tool.

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 unnecessary words, front-loading the verb 'Set' and specifying the target. It is perfectly concise for the information it conveys, though this brevity contributes to incompleteness in other dimensions.

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?

The tool has four parameters, no output schema, and no annotations, yet the description provides only a basic statement. It lacks essential context about the operation's effect on the scene file, whether it can be undone, or what the expected outcome is. Sibling tools like read_mesh_instance exist but are not cross-referenced.

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?

All four parameters have descriptions in the schema (100% coverage), so the baseline is 3. The tool description adds no additional meaning about parameter interactions, constraints, or relationships beyond what the schema already provides. It neither improves nor degrades the baseline.

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 specifies the action: setting a surface material on a MeshInstance. It distinguishes itself from sibling tools like set_material_param by naming the exact target resource and object type. The one-sentence description is unambiguous and leaves no doubt about what the tool does.

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?

No usage guidance is provided. The description does not indicate when to use this tool versus alternatives such as set_material_param or write_resource, nor does it mention prerequisites like having the scene open. There are no exclusions or context about typical workflows.

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