spawn_nav_modifier_volume

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

Annotations already cover the write/safety profile (readOnly=false, destructive=false, idempotent=false, openWorld=false), and the description adds context by locating the spawn in the editor world and by enumerating the return payload at a time when no output schema exists. It still says nothing about whether the navmesh must be rebuilt afterwards or whether the new actor must be saved/committed.

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?

Two compact lines with the action front-loaded and no filler. The trailing Returns list is arguably better rendered as prose, but since no output schema exists it is earning its space.

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?

For a spawn/mutation tool with no output schema, the description supplies purpose and the return shape, which is the minimum viable set. It omits prerequisites and follow-up actions (navigation rebuild, saving the level) that an agent would need to complete the task reliably.

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%, so extent, location and area_class are already fully documented, including the 100,100,100 default. The description only echoes 'box brush' and hints at area-class application via the returned area_class_applied field; the baseline 3 applies when the schema does the heavy lifting.

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?

States a specific verb and resource: it spawns an ANavModifierVolume with a box brush in the editor world. The named class and brush make it identifiable, but it never contrasts itself with the nearby spawn_navmesh_bounds_volume or spawn_nav_link_proxy, so sibling differentiation is left to the caller.

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?

There is no when-to-use guidance, no prerequisites (e.g. the volume only affects navigation once rebuilt), and no named alternative among the nav-related siblings. The description is purely declarative about what the call does.

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