run_luaRun custom Lua code in Aseprite to extend functionality beyond built-in tools, with rollback on failure and undo backup for safety.
执行任意 Lua（逃逸舱）。必须 unsafe=true 且 confirmed=true。
与 op 批量同样受快照保护：snippet 失败会回滚文档，成功则把改前状态留作 undo 备份。 CLI 模式下每次调用都会重写 .ase，所以 changed 表示"文档被重写"而非"内容语义变化"。
| Name | Required | Description | Default |
|---|---|---|---|
| code | Yes | ||
| unsafe | No | ||
| confirmed | No | ||
| session_id | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds rich behavioral context beyond the destructiveHint/openWorldHint annotations: snippet failure rolls back the document, success creates an undo backup, and CLI mode rewrites .ase so changed means 'rewritten' rather than 'semantically changed.' This is exactly the kind of non-obvious behavior an agent needs.
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 compact and front-loaded: purpose and safety gate first, then snapshot/rollback behavior, then CLI caveat. Every sentence carries distinct operational value with no filler.
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?
Given there is no output schema, the description does well to explain safety gating, rollback, undo behavior, and the meaning of changed in CLI mode. The main gaps are the unexplained session_id parameter and reliance on the reader already knowing apply_operations' snapshot 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 0%, so the description must compensate. It gives real meaning to unsafe and confirmed (both must be true) and implies code is the Lua snippet to execute. However, session_id — a required parameter — is never explained.
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 'Execute arbitrary Lua (escape hatch)' — a specific verb and resource, and clearly frames this as an escape hatch beyond normal operations. It doesn't explicitly name sibling alternatives, but the scope is unmistakable.
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 'escape hatch' wording implies use when standard operations or inspection are insufficient, and it explicitly mandates unsafe=true and confirmed=true. However, it never states when to prefer this over apply_operations or inspect, nor gives any when-not-to-use guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.