Set the value of a shader node input in Blender by specifying the material, node name, and value. Adjust shader parameters directly for materials.
Set the value of a shader node input.
Args: material_name: Target material. node_name: Node name/label. value: Value to set.
| Name | Required | Description | Default |
|---|---|---|---|
| value | Yes | ||
| node_name | Yes | ||
| material_name | Yes |
Changes observed during successful MCP inspections.
v3.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
There are no annotations, so the description carries the full burden of behavioral disclosure. It only states the basic mutation and does not mention value encoding, side effects, failure behavior, or whether the operation is destructive or reversible.
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 front-loaded with the core action and followed by a compact, scannable Args block. There is no filler or redundant prose; every line is short and contributes to the overall structure.
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?
For a 3-required-parameter mutation tool with no annotations and no output schema, this description is incomplete. An agent needs to know how to format the value string and what preconditions apply, but neither is provided.
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?
With 0% schema description coverage, the description must compensate, but it only gives minimal one-line glosses. 'value: Value to set' is circular, and it does not explain how to encode numbers, colors, vectors, or other shader input types as strings.
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?
The description states a specific verb and resource: 'Set the value of a shader node input.' This clearly differentiates it from sibling tools like add_shader_node and connect_shader_nodes, which create or wire nodes rather than modify an input value.
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 guidance is given about when to use this tool versus alternatives such as set_material_property or connect_shader_nodes. The agent must infer the intended use solely from the name and one-line purpose, with no mention of prerequisites like the material or node already existing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.