mat_list

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds the paginated behavior and the output contents (class, name, usedBy), which are genuinely useful beyond the annotations. It doesn't mention ordering or edge cases, but for a safe read-only listing tool the added context is sufficient.

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 front-loaded with the action and outputs, and the workflow hint is bolded for visibility. The bilingual repetition is intentional and not wasteful, though it does double the length compared to a single-language description.

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 no output schema, the description correctly mentions the returned fields (class, name, usedBy) and pagination. The two simple parameters are fully covered by the schema, and the workflow guidance ties this tool into the broader material editing process. Minor missing details like sorting order are not critical for correct invocation.

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 100%, so the baseline is 3 even without additional parameter information. The description's mention of pagination provides some context for limit/offset but doesn't add meaningful semantics beyond the schema definitions.

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 uses a specific verb and resource: 'List every material in the scene' with class, name, and usedBy count. It also explicitly frames this as the tool to confirm material names before using mat_get or mat_assign, which distinguishes it from those siblings.

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 bold instruction 'Confirm the material name here before passing it to mat_get or mat_assign' gives clear context and names the follow-up tools. It lacks explicit when-not-to-use guidance, but the stated workflow is actionable and specific.

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