Set a shader parameter's value on a node's ShaderMaterial to control visual effects in real time.
Set a shader parameter on a node's material
| Name | Required | Description | Default |
|---|---|---|---|
| value | Yes | Value to set (number, object, array, etc.) | |
| nodePath | Yes | Path to the node with a ShaderMaterial | |
| typeHint | No | Optional type hint (e.g. "Color", "Vector2") | |
| paramName | Yes | Shader parameter name |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of behavioral disclosure. It only states the action, without mentioning side effects, shared-material implications, failure modes when the node lacks a ShaderMaterial, or whether the change is immediately visible.
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 a single, front-loaded sentence with zero wasted words. It is appropriately concise for a simple tool, though it omits some useful behavioral context that would make it more informative.
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?
The schema covers all parameters, but there is no output schema, no annotations, and no guidance on alternatives, side effects, or expected return behavior. The description is minimally viable for invocation but leaves notable gaps for an agent operating autonomously.
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 baseline is 3. The tool description adds no parameter-specific meaning beyond what the schema already provides; the schema descriptions for nodePath, paramName, typeHint, and value are adequate.
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 clearly states the action (set) and the target (shader parameter on a node's material). It is unambiguous, though it does not explicitly differentiate from sibling tools like game_set_property or manage_shader.
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 provided on when to use this tool versus alternatives such as game_set_property, manage_shader, or game_visual_shader. There are no exclusions, prerequisites beyond the schema's nodePath note, or conditions for selection.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.