assign_material

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

The description discloses important behavioral traits beyond what annotations (none provided) would cover: it specifies the return dict contents and explicitly states that binding failures raise ValueError and will not be silently swallowed as success:True. This adds transparency about error handling and return behavior, though it does not mention permissions or side effects on existing assignments.

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 well-structured: it opens with the main purpose, then lists parameter explanations in a clear, bullet-like format, and finishes with return and error behavior. Every sentence is informative and contributes to understanding the tool, with no fluff or redundancy.

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 description is comprehensive for a simple assignment tool. It covers the action, all relevant parameters (except ctx), the return dict contents, and error handling semantics. Since there is no output schema, the description provides the necessary return information, making it complete for the agent to invoke and interpret results.

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?

The schema provides only parameter names with no descriptions (0% coverage), so the description carries the full burden. It explains geometry_path and material_path as node paths, and gives detailed semantics for the 'group' parameter, including the None vs specific group behavior. However, the required 'ctx' parameter is not described at all, leaving a small gap.

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 tool's action: binding a material at material_path to a geometry node at geometry_path. The verb 'bind' and the specific resource paths make the purpose unambiguous, and it is distinct from sibling tools like list_materials or create_material.

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 clear context on how to use the tool, including optional group binding behavior and the distinction between None and a specific group. However, it does not explicitly state when to use this tool over alternatives, such as set_parameters or other material-related tools, nor does it mention any exclusions or prerequisites.

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