add_usd_payload

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

Annotations already disclose readOnlyHint=false, destructiveHint=false, and idempotentHint=false. The description adds valuable context beyond those: payloads are not loaded unless an explicit Load rule exists, and it provides the return shape (stage_name, prim_path, asset_path, added, position, errors). It does not cover permission requirements or failure modes beyond the errors array.

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 sentences front-load the operation and its key behavioral caveat, followed by an inline return shape. No filler or redundancy.

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 no output schema, the description compensates by including the return fields, and it explains the load-on-demand behavior. Annotations cover safety, but the description omits when to prefer payloads over references, which would be helpful in this large USD toolset.

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 the schema already documents all five parameters including defaults and the add_usd_reference vocabulary for position. The description adds no additional parameter meaning beyond what the schema provides, fitting the 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 ('Add a payload composition arc to a prim') and differentiates the payload mechanism from references by emphasizing load-on-demand behavior. It does not explicitly name the sibling add_usd_reference as an alternative, so sibling differentiation is implied rather than stated.

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 explicit when-to-use or when-not-to-use guidance; the description describes what a payload does but does not say when to choose a payload arc over a reference or internal reference. The only sibling mention is buried in the schema's position parameter description.

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