Set VEX code on an existing Attribute Wrangle node using its node path and a VEX snippet, enabling scripted updates to Houdini wrangle logic.
Set VEX code on an existing Attribute Wrangle node.
Args: node_path: Path to the wrangle node. vex_code: VEX snippet to set.
| Name | Required | Description | Default |
|---|---|---|---|
| vex_code | Yes | ||
| node_path | Yes |
Changes observed during successful MCP inspections.
v2.24.1Input schema / additionalPropertiesAdded value: +falsev0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. The description doesn't state whether setting code replaces existing code, whether the node's cook state is dirtied, whether errors are raised on invalid VEX, or any side effects. For a mutation tool with zero annotation coverage, this is a serious gap.
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?
The description is short and front-loaded with the core action, but the Args section adds little value by merely echoing parameter names. It is not padded, but three of four lines are low-information.
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 mutation tool with no annotations, no output schema, and 0% parameter coverage should do much more. It omits prerequisites, error behavior, replacement semantics, and parameter details, leaving an agent without enough context to invoke it correctly.
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%, so the description must compensate. It only restates the parameter names with generic labels ('Path to the wrangle node', 'VEX snippet to set'). It adds no format details, path syntax, code constraints, or meaning beyond what the bare parameter names already convey.
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 (Set) and resource (VEX code on an Attribute Wrangle node). The sibling set includes create_wrangle, get_wrangle_code, and validate_vex, so the description distinguishes itself by specifying this sets code on an EXISTING node rather than creating one. However, it doesn't explicitly contrast itself with get_wrangle_code beyond the obvious Set/Get distinction.
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 when-to-use guidance, no prerequisites (e.g., must the node already exist?), no exclusions, and no mention of alternatives like validate_vex for syntax checking or create_wrangle for new nodes. The reader is left to infer usage context entirely.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.