ue_spatial_query

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds value by detailing the behavior of each mode (e.g., 'N closest actors', 'penetration depth', 'union AABB', 'actors inside box'). This goes beyond what annotations provide, though it could mention that results are returned as a list or other format.

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 concise, consisting of two sentences that front-load the purpose and then list modes. There is no redundant information. It could be slightly more structured (e.g., bullet points for modes), but it is clear and efficient.

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 complexity (12 parameters, 1 required, with output schema), the description provides a good high-level overview and explains mode and filters. However, it omits critical details about spatial parameters (coordinates, extents) which are central to the tool's operation. The presence of an output schema somewhat reduces the need to explain return values, but the missing parameter details leave the description incomplete.

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. The description explains the 'mode' parameter and mentions 'class_filter' and 'tag_filter', but fails to describe many other parameters (x, y, z, count, actor_a, actor_b, extent_x, extent_y, extent_z). With 12 parameters and no schema descriptions, the tool description should compensate by explaining these, but it does not.

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 purpose: 'Reason about actor positions and volumes.' It enumerates four distinct modes with brief explanations, making the tool's function very specific. The sibling tools (e.g., ue_ground_trace, ue_get_actor_hierarchy) are clearly different in purpose, so this tool is well-differentiated.

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 explains each mode's behavior (nearest, overlap, combined_bounds, box_contents) and implies usage for spatial queries. It does not explicitly state when not to use this tool or compare it to siblings, but given the unique nature of the sibling tools, the guidance is sufficient for a typical use case.

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