Edit prefab assets¶

Use prefab(action="edit") to change a prefab asset without unpacking an instance into the open scene. The change affects future instances and existing instances that have not overridden the edited property.

Choose the target¶

Goal	Tool
Change the prefab asset	`prefab(action="edit")`
Change one scene instance	`set_property` or `manage_component`
Push instance overrides to its prefab	`prefab(action="apply")`
Discard instance overrides	`prefab(action="revert")`

Keep prefab assets under version control. Asset editing is durable and does not have the same recovery guarantees as a scene-only Unity Undo operation.

Change a serialized property¶

result = await prefab(
    action="edit",
    asset_path="Assets/Prefabs/Player.prefab",
    component="Health",
    prop="MaxHP",
    value="150",
)

The component must exist on the selected prefab object and prop must resolve to a Unity-serialized property. Use the serialized property name shown by the component/schema tools; ordinary C# reflection-only properties are not edited.

To target a child, pass its path relative to the prefab root through path:

await prefab(
    action="edit",
    asset_path="Assets/Prefabs/Player.prefab",
    path="Visual/Nameplate",
    component="TextMeshProUGUI",
    prop="m_text",
    value="Player",
)

Add or remove a component¶

await prefab(
    action="edit",
    asset_path="Assets/Prefabs/Bomb.prefab",
    add_component="Rigidbody",
)

await prefab(
    action="edit",
    asset_path="Assets/Prefabs/SilentEnemy.prefab",
    remove_component="AudioSource",
)

The operation is idempotent when the requested component is already present or absent. Pass path as well to operate on a prefab child.

Create, save, and instantiate¶

A common workflow is:

# 1. Design a scene object.
await create_object(name="EnemyTemplate", components="Health")
await set_property(
    path="/EnemyTemplate",
    component="Health",
    prop="MaxHP",
    value="100",
)

# 2. Save and connect it as a prefab asset.
await prefab(
    action="save",
    path="/EnemyTemplate",
    asset_path="Assets/Prefabs/Enemy.prefab",
    mode="new",
)

# 3. Edit the asset without opening Prefab Mode.
await prefab(
    action="edit",
    asset_path="Assets/Prefabs/Enemy.prefab",
    component="Health",
    prop="MaxHP",
    value="150",
)

# 4. Instantiate with an explicit scene name, parent, or object name.
await create_object(
    name="Enemy_01",
    parent="/Enemies",
    prefab_path="Assets/Prefabs/Enemy.prefab",
    scene="Level01",
)

prefab(action="instantiate", asset_path=...) is the minimal shortcut for an unrenamed instance in the active scene. Its public wrapper does not accept name, parent, or scene; use create_object(prefab_path=...) when any of those controls is required.

Verify the asset change¶

Instantiate a disposable scene copy and read the exact property:

await create_object(
    name="PrefabVerification",
    prefab_path="Assets/Prefabs/Player.prefab",
)
actual = await get_component(
    path="/PrefabVerification",
    type="Health",
    fields="MaxHP",
)

Delete the verification object after checking the result. For instance overrides, use prefab(action="get_overrides", path=..., format="structured") before applying or reverting them.

See Asset Tools for the full prefab action overview and Object Tools for scene-object editing.