spawn_exponential_height_fog

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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent operation, so the safety profile is covered. The description adds real value by enumerating the return payload, notably 'spawned' and 'density_set' flags that confirm whether the effect actually took hold. It still says nothing about duplicate-actor behavior, required editor/PIE context, or whether the spawn is persistent.

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 sentences, front-loaded with the action, with the return shape appended. No filler or redundancy, though the return-object enumeration is dense and could have been compressed if an output schema existed.

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 simple two-parameter spawn tool, the description covers the action, the optional density side effect, and — importantly — the return fields, which compensates for the absent output schema. The remaining gap is contextual: which level/world the actor lands in and what happens on repeat calls.

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 both parameters (location, fog_density) are already fully documented in the schema, which sets the baseline at 3. The description mentions only the density parameter and adds no format or default information beyond the schema, and never mentions the location parameter.

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 ('Spawns') and resource ('ExponentialHeightFog actor'), plus the optional density write. It does not explicitly differentiate itself from siblings like get_exponential_height_fog_properties or set_exponential_height_fog_properties, but the word 'spawn' plus the actor-class name is enough for an agent to distinguish creation from property mutation.

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?

No indication of when to use this versus alternatives (set_exponential_height_fog_properties for an existing actor, or spawn_sky_atmosphere / spawn_volumetric_cloud for other atmosphere actors). There is also no stated precondition such as whether a fog actor must not already exist in the level.

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