wb_rng_create

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

With no annotations supplied, the description must carry the full behavioral burden, and it does disclose the single most important safety fact: the call is a dry-run unless write=true. That is genuine, non-redundant context. However, nothing is said about required permissions, whether an existing group is replaced, what the dry-run response contains, or how seeding affects reproducibility, so the mutation profile is only partially covered.

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 short, front-loaded sentences with zero filler: purpose first, execution-mode caveat second. It is efficient, though the terseness here edges toward under-specification rather than disciplined brevity.

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?

A 12-parameter mutation tool with no annotations, no output schema, and no parameter documentation needs far more than two sentences. The dry-run caveat helps, but an agent still cannot confidently populate the placement, randomization, or parentage parameters from this definition alone.

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% across 12 parameters, so the schema contributes almost no meaning, and the description explains only the write flag. Nothing clarifies x/y/z positioning, the file/parent/name triple, or the interaction between rule, fixed_mode, seed, total and percentage — the parts an agent is most likely to get wrong. This is well below what the coverage gap demands.

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?

"Create a native World Builder Randomized Nested Group" gives a specific verb plus a fairly distinctive resource type that none of the sibling tools (scatter, array, generate_*) produce, so an agent can identify the artifact being created. It stops short of stating how this differs from adjacent procedural-placement tools like wb_scatter or wb_array, which is the only thing keeping it from a 5.

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 says nothing about when to reach for this tool versus the many neighboring placement/generation siblings. The one conditional clause present (write semantics) governs execution mode, not tool selection, so there is effectively no when-to-use guidance.

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