mat_slots

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that only occupied slots are returned and the data type (class and name), but does not disclose edge cases like empty slot behavior or return structure. This modest addition fits a 3.

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 and front-loaded with the key action and output. The bilingual Chinese/English repetition is slightly redundant, but each version serves a different audience, so it remains compact and purposeful.

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 read-only tool with zero parameters and no output schema, the description explains what it returns (class and name of occupied slots) and why to call it. It could be more explicit about the exact return format (e.g., array of objects), but it is sufficient 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?

The tool has zero parameters and an empty input schema, so parameter semantics are trivially satisfied. The baseline of 4 applies because there are no parameters to document and no risk of ambiguity.

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 identifies the verb ('Read'), the resource ('the 24 Material Editor slots'), and the exact output ('the class and name of each occupied slot'). It also differentiates itself from sibling mat_set_slot by explicitly stating it is the entry point before setting a slot.

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?

It gives explicit usage context: use it to place a material into the editor or to find an empty slot before mat_set_slot. However, it does not mention when not to use it or compare with alternative listing tools like mat_list, so it stops short of full exclusion guidance.

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