Execute Lua scripts in Aseprite headless to automate custom pixel-art workflows and extend asset generation.
Execute arbitrary Lua script inside Aseprite headless environment for advanced custom workflows.
| Name | Required | Description | Default |
|---|---|---|---|
| code | Yes | Lua script content to execute | |
| params | No | Parameters accessible via app.params |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full behavioral burden. It mentions the headless environment and that scripts are 'arbitrary', but it does not disclose side effects, sandboxing, permissions, whether scripts can modify project files, or error/timeout behavior — all critical for arbitrary code execution.
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?
A single sentence that is front-loaded with the core action and resource, with no wasteful clauses. Every word contributes to the purpose.
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 an arbitrary code-execution tool with no annotations and no output schema, the description is inadequate. It omits crucial context such as sandbox limitations, what APIs are available to the script, or what side effects are possible, leaving the agent unable to assess risk or expected behavior.
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 both parameters ('code' and 'params') are already documented in the schema. The description adds no syntax, format, or usage guidance beyond what the schema provides, making the baseline of 3 appropriate.
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 ('Execute') and resource ('arbitrary Lua script') within a named environment ('Aseprite headless environment'). It does not explicitly name or distinguish itself from siblings like aseprite_run_pipeline, though 'advanced custom workflows' hints at a general-purpose alternative to the dedicated tools.
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?
The phrase 'for advanced custom workflows' implies usage when dedicated tools are insufficient, but it never states when to prefer this over aseprite_run_pipeline or the many specific operation tools, nor any exclusions or prerequisites.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.