ue_umg_set_slot

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

With no annotations provided, the description carries the burden of explaining behavior. It details valid property keys per slot type and explains data transformations (2-number lists become Vector2D, 4-number lists become Margin). It does not mention permissions, error handling, or whether this replaces existing layout settings, but the core mutation behavior and accepted inputs are well disclosed.

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 with a concise opening sentence followed by a bulleted breakdown of valid keys per slot type. The format examples are compact and add value without redundancy. Every sentence contributes useful information.

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?

Given the tool's moderate complexity and lack of output schema, the description covers the essential aspects: how to determine slot_class, what keys are valid, and how values are converted. It lacks details on error handling or prerequisites (e.g., widget must already exist in a panel), but the provided information is sufficient for typical usage.

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%, but the description heavily compensates by explaining the `properties` parameter in detail, including per-slot-class valid keys and value formats. The other two parameters (`widget` and `widget_blueprint_path`) are not described, but their purpose is reasonably inferable from their names.

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 function: setting the layout of a widget within its panel. It distinguishes itself from sibling tools like ue_umg_set_widget_property by focusing specifically on slot/layout properties, and it references ue_umg_tree_info to determine the slot class.

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 for when to use the tool: when setting layout properties on a widget's slot. It explicitly instructs users to check ue_umg_tree_info for the slot_class before choosing valid keys, which gives strong usage guidance. It does not explicitly mention alternatives or exclusion cases, but the context is clear enough.

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