Editor Automation

Select the automation surface

Read references/selector-architecture.md.

• Use a Scripted Action for a contextual operation on selected assets or actors.
• Use an Editor Utility Widget for a persistent dockable UI and human-reviewed batch work.
• Use Call in Editor for an action attached to a placed Actor that also has runtime use.
• Use a Scriptable Tool for modal viewport interaction with accept/cancel semantics.
• Use Python for text-based pipelines, cross-DCC integration, and repeatable batches.
• Use a commandlet for unattended/headless work and CI.
• Use Data Validation for asset invariants, not as a general behavior-test framework.
• Use Automation/Functional Tests for code, system, map, gameplay, and regression checks.
• Use Unreal MCP only for bounded AI tool calls in 5.8; it is Experimental.

Execute safely

1. Define selection/input scope, mutation set, source-control behavior, undo boundary, save policy, cancellation, logs, and validation before writing the tool.
2. Separate discovery and planning from mutation. Produce a dry-run report for destructive, bulk, or difficult-to-reverse work.
3. Use editor APIs for assets and packages. Never move, rename, or delete .uasset files with generic filesystem operations.
4. Use get_editor_property/set_editor_property when scripting reflected editor data so editor change notifications run.
5. Wrap only genuinely undoable changes in a transaction. Import, save, source-control, and many package operations are not made reversible by a transaction.
6. Mark changed objects/packages dirty, save deliberately, and report every failure.
7. Make reruns idempotent or detect prior output. Test on a disposable subset before the full content tree.
8. Run validation/tests and inspect the actual diff before submission.

Load the task reference:

• UI/Blueprint tools: references/editor-utilities-blueprint.md
• Python execution/APIs: references/python-workflows.md
• mutation guardrails: references/safe-asset-mutation.md
• command line/CI: references/commandlets-headless-ci.md
• Data Validation: references/data-validation.md
• test frameworks: references/automation-tests.md
• Unreal MCP: references/unreal-mcp.md
• concrete tools: references/patterns.md
• recovery: references/debugging-recovery.md

Hard rules

• Never operate directly on .uasset/.umap files with os, shutil, or shell moves.
• Never run a bulk mutation before a scoped dry run or disposable-copy test.
• Never assume a transaction makes import, save, delete, or source-control work reversible.
• Never autosave unrelated dirty packages.
• Never suppress per-asset failures and still report success.
• Never run Python as gameplay code; UE 5.8's embedded Python is editor-only.
• Never expose Unreal MCP beyond loopback; it has no authentication layer.
• Never issue overlapping Unreal MCP tool calls; the server serializes them on the game thread.
• Never let an AI infer permission for destructive or project-wide mutations.

See references/sources.md for the UE 5.8 source trail.