## Update a variation's memory layer assignment

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

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

### Path Parameters

- `workspaceId: string`

- `agentId: string`

- `variationId: string`

- `id: string`

### Body Parameters

- `position: optional number`

  New position. Only field currently updatable on an assignment.

### Returns

- `VariationMemoryLayerAssignment object { id, memoryLayer, position }`

  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: optional string`

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

  - `memoryLayer: optional 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: optional string`

    - `name: optional 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: optional number`

    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

```http
curl https://api.cadenya.com/v1/workspaces/$WORKSPACE_ID/agents/$AGENT_ID/variations/$VARIATION_ID/memory_layer_assignments/$ID \
    -X PATCH \
    -H 'Content-Type: application/json' \
    -H "Authorization: Bearer $CADENYA_API_KEY" \
    -d '{}'
```

#### Response

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