## Update a variation's memory layer assignment

`agents.variations.update_memory_layer(id, **kwargs) -> VariationMemoryLayerAssignment`

**patch** `/v1/workspaces/{workspaceId}/agents/{agentId}/variations/{variationId}/memory_layer_assignments/{id}`

Updates the position of a memory layer assignment on a variation.

### Parameters

- `workspace_id: String`

- `agent_id: String`

- `variation_id: String`

- `id: String`

- `position: Integer`

  New position. Only field currently updatable on an assignment.

### Returns

- `class VariationMemoryLayerAssignment`

  VariationMemoryLayerAssignment attaches a single MemoryLayer to a
  variation at a given position in the variation's baseline memory
  stack. A variation has at most one assignment per memory_layer_id.

  Variations only support whole-layer attachments — entry pinning is an
  objective-level capability.

  - `id: String`

    Assignment row id — handle for removing the assignment. Distinct
    from the referenced memory layer's id.

  - `memory_layer: BareMetadata`

    BareMetadata contains the minimal metadata for a resource: the ID and an
    optional human-readable name. These are used for reference fields where the
    full metadata (account scoping, timestamps, labels, external IDs) is not
    needed — e.g., the tool references inside an agent variation spec or the
    tools assigned to an objective. Both fields are server-populated; clients
    provide IDs through sibling fields rather than by constructing a
    BareMetadata themselves.

    - `id: String`

    - `name: String`

      Human-readable name of the referenced resource, populated by the server
      on reads for convenience. Absent on references to resources that do not
      have a name (e.g., objective tasks).

  - `position: Integer`

    Position in the variation's baseline stack. Lower values sit lower;
    the highest-position assignment is on top of the variation's
    baseline. Gaps are fine — only relative position matters. Positions
    must be unique within a variation; a request that would collide
    with an existing assignment's position is rejected with
    InvalidArgument.

### Example

```ruby
require "cadenya"

cadenya = Cadenya::Client.new(api_key: "My API Key")

variation_memory_layer_assignment = cadenya.agents.variations.update_memory_layer(
  "id",
  workspace_id: "workspaceId",
  agent_id: "agentId",
  variation_id: "variationId"
)

puts(variation_memory_layer_assignment)
```

#### Response

```json
{
  "id": "id",
  "memoryLayer": {
    "id": "id",
    "name": "name"
  },
  "position": 0
}
```