ue_umg_add_widget

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 key behaviors: the widget is placed under the specified panel (or root if parent omitted), slot layout is applied immediately, and the name parameter affects C++ BindWidget and is auto-generated if omitted. It also notes the parent must be a PanelWidget. It does not mention error handling or whether the blueprint must be open, but covers the primary behavioral traits.

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 one-sentence summary followed by an Args block. Each bullet is directly useful, providing examples and constraints without redundant information. It is appropriately sized for the complexity of five parameters.

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 (5 params, no output schema), the description is quite complete. It explains all parameters, constraints, and immediate behavior. It does not mention possible error conditions or prerequisites beyond parent being a PanelWidget, but it is sufficient for an agent to invoke the tool correctly.

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 schema has 0% description coverage, with only types and titles. The description adds extensive meaning for every parameter: examples for widget_blueprint_path, a list of valid widget_class values, parent default behavior, name usage and auto-generation, and slot keys referencing ue_umg_set_slot. This fully compensates for the schema's lack of descriptions.

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 action with a specific verb+resource: 'Crea un widget e lo mette sotto un pannello dell'albero' (Creates a widget and puts it under a tree panel). This distinguishes it from siblings like ue_umg_remove_widget, ue_umg_set_widget_property, and ue_umg_set_slot, which operate on widgets differently.

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 clear context for when to use the tool: adding a widget to a UMG tree under a panel. It includes constraints (parent must be a PanelWidget) and references an alternative tool for setting slot properties (ue_umg_set_slot). However, it does not explicitly state when not to use it or mention other alternatives, so it is slightly below a perfect score.

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