set_item_spacing

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states the action without mentioning side effects (e.g., that it mutates the frame) or important constraints such as itemSpacing being ignored when primaryAxisAlignItems is SPACE_BETWEEN. The description is too terse to adequately inform the agent about the tool's behavior.

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, direct sentence with no filler and is front-loaded with the verb and resource. It is exactly as concise as needed for the tool's purpose.

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 is a simple setter, but the description omits mention of counterAxisSpacing and the SPACE_BETWEEN/WRAP interactions that affect behavior. However, the schema covers these details, so the description is adequate for initial selection but not fully complete on its own.

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%, with detailed descriptions for itemSpacing and counterAxisSpacing. The description adds no parameter-level information beyond the general concept of setting spacing, so it meets the baseline but does not enhance understanding.

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 'Set' with a clear resource 'distance between children' and scope 'in an auto-layout frame', making it distinct from sibling layout tools like set_padding or set_axis_align. This clarity allows an agent to immediately understand the tool's function.

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 implies usage on auto-layout frames but does not explicitly state when to use this tool over alternatives, name any exclusion cases, or mention prerequisites. No guidance is given on when not to use it, though the auto-layout context provides some implied direction.

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