set_line_width

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

No annotations are provided, so the description carries the full burden. It discloses the exclusivity constraint but does not mention whether the operation is a mutation, whether it affects existing objects, whether it requires a selected layer, or what the return value is. For a mutating tool, this is a significant gap.

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?

One sentence, front-loaded with the action and resource, and the critical exclusivity rule is included. Every word earns 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?

The tool has 3 parameters, no annotations, and an output schema. The description covers the key selection rule but omits behavioral details like mutation effects, error conditions, and return value. It is adequate for a simple setter but not fully complete.

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 0%, so the description must compensate. It explains the relationship between 'layer' and 'names' (exactly one) and that 'width' is the value to set. However, it doesn't clarify the format of 'names' (array of object names) or the units/range of 'width', leaving some 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 states a specific verb ('Set') and resource ('line width of a layer OR of objects'), and it distinguishes the two target modes. It doesn't explicitly differentiate from sibling tools like set_line_style or set_properties, but the resource and action are clear enough to identify what it 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?

The description gives a clear usage constraint: 'give exactly one of layer / names'. This tells the agent when to use which parameter and implies mutual exclusivity. It doesn't explicitly name alternatives or when-not-to-use, but the instruction is actionable and context-rich.

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