create_pcg_graph

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

The description does add real behavioral context beyond the annotations: headless-safe via CreatePackage + NewObject<UPCGGraph>, implicit Input/Output nodes, node_count counting only user-added nodes, and the PCG plugin requirement. However, it claims the operation is idempotent ("or loads, idempotently"), which directly conflicts with idempotentHint=false — a trait agents use to decide retry policy — so this is flagged as an annotation contradiction and caps the score.

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?

Purpose is front-loaded in the first clause and the paragraph is short. The CreatePackage/NewObject implementation detail is somewhat extraneous but brief and justified by the headless-safety claim, so structure is efficient overall.

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?

There is no output schema, so the detailed Returns block is genuinely load-bearing and tells the agent how to interpret created/already_exists/node_count/save_error. Coverage of the plugin prerequisite and idempotent-load behavior makes the call executable, though collision/error handling beyond save_error is left implicit.

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% (name and package_path, including the /Game/PCG default), so the schema already documents every parameter. The description adds nothing further about argument semantics, syntax, or constraints, making 3 the correct baseline.

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: creates (or loads) and saves a UPCGGraph asset, which is distinguishable from sibling PCG tools such as add_pcg_node, remove_pcg_node, or spawn_pcg_volume. It does not explicitly contrast itself with any sibling, so a 4 rather than 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?

"Requires the PCG plugin to be enabled" gives one useful prerequisite, but there is no guidance on when to use this versus the other graph-creation/PCG tools, what to do if the name already exists, or how this fits into a workflow (e.g., it is the prerequisite step before add_pcg_node). Usage is only implied.

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