Reverse the most recent change in the Unreal Editor to restore the previous state and recover from mistakes quickly.
Undo the last editor action.
This tool declares no required parameters. Add optional parameters from the input schema as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {},
"name": "undo"
}
}| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description must convey behavioral traits. It states 'Undo the last editor action' but does not disclose that it modifies state, whether it is reversible, or what happens if there is no prior action. It does not contradict annotations, but is too sparse to inform an agent about side effects.
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, concise sentence that is front-loaded with the essential information. Every word earns its place, and there is no redundancy or fluff.
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 simple tool with no parameters and no output schema, the description is sufficient to convey the operation. However, it could optionally mention edge cases (e.g., no-op if nothing to undo), but given the simplicity, it is largely complete.
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?
The tool has zero parametersches, and the schema description coverage is 100% (empty properties). The baseline for 0 params is 4, and the description adds nothing beyond the schema because there is nothing to explain. This is 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?
The description 'Undo the last editor action' clearly specifies the operation (undo) and resource (editor action), distinguishing it from sibling tools like redo and get_undo_history. The verb and target are precise and unambiguous.
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 description provides no guidance on when to use this tool versus alternatives like get_undo_history or redo. It does not mention prerequisites, conditions, or exclusions. While the function is obvious, explicit guidance is absent.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.