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set_usd_attribute

Assign a value to a USD attribute on a prim in a live Houdini session to modify scene data directly.

Instructions

Set a USD attribute value.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
pathYes
valueYes
attr_nameYes
prim_pathYes

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
resultYes

Schema Changelog

Changes observed during successful MCP inspections.

  1. First observedv0.1.0

TDQS

C2.4/5.0
Behavior2/5

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

No annotations are provided, so the description carries the full behavioral burden. 'Set' implies a mutation, but nothing states whether the write persists to the stage, requires editing permissions, overwrites vs creates the attribute, or if it is undoable. For a mutating tool this is a significant gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single short sentence with no waste, but it is under-specified rather than truly concise. It is front-loaded and readable, yet it omits everything an agent would need.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be explained. But with 4 fully undocumented required parameters, no annotations, and no sibling differentiation, the description is too thin for a mutation tool in a crowded USD/parameter tool set.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters2/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% for 4 required parameters (path, value, attr_name, prim_path), and all are required with no titles beyond the raw property names. The description only vaguely gestures at 'attribute' and 'value', leaving the distinction between path and prim_path and the expected value type entirely undocumented.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose3/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Set a USD attribute value'), which is more than a tautology. However, it gives no differentiation from related siblings like get_usd_attribute, set_parameter, or lop_prim_get, so an agent cannot tell which setting tool applies to a USD prim.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

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, and no mention of alternatives such as set_parameter or set_parameters. The agent must infer from the name alone when this is the correct tool.

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