> ## Documentation Index
> Fetch the complete documentation index at: https://cadenya.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Reposition a memory layer
> Change a layer's position in a variation's cascade without detaching it.
Move an [attached memory layer](/docs/api-reference/agentvariationservice/attach-a-memory-layer-to-a-variation) to a new [position](/docs/guides/memory-layers) in the variation's cascade. `position` is the only thing an assignment holds that you can change, so this is a one-field update.
```typescript TypeScript theme={null}
const assignment = await client.agents.variations.updateMemoryLayer(agentId, variationId, assignmentId, {
workspaceId,
position: 5,
});
console.log(assignment.position); // 5
```
```go Go theme={null}
assignment, err := client.Agents.Variations.UpdateMemoryLayer(ctx, agentID, variationID, assignmentID,
cadenya.AgentVariationUpdateMemoryLayerParams{
WorkspaceID: cadenya.String(workspaceID),
Position: cadenya.Int(5),
})
if err != nil {
log.Fatal(err)
}
log.Println(assignment.Position) // 5
```
```ruby Ruby theme={null}
assignment = cadenya.agents.variations.update_memory_layer(
agent_id,
variation_id,
assignment_id,
workspace_id: workspace_id,
position: 5
)
puts assignment.position # 5
```
```bash cURL theme={null}
curl -X PATCH "https://api.cadenya.com/v1/workspaces/${WORKSPACE_ID}/agents/${AGENT_ID}/variations/${VARIATION_ID}/memory_layer_assignments/${ASSIGNMENT_ID}" \
-H "Authorization: Bearer ${CADENYA_API_KEY}" \
-H "Content-Type: application/json" \
-d '{ "position": 5 }'
```
The `id` in the path is the assignment's own `avml_...` value, from the attach response or the variation's `info.memoryLayerAssignments`, not the layer's id. Read `info.memoryLayerAssignments` back and the new position is reflected there.
## Why reposition instead of re-attach
You cannot attach the same layer twice, that is a `409`. So when a layer sits in the wrong spot in the cascade, this is how you fix it: change its position rather than detaching and re-adding. Lower positions are more specific and win a shared key, so lowering a layer's position promotes its version of any key it shares with another layer.
## Related
Where the assignment and its `position` come from.
Detach the layer entirely.
How `position` resolves a key across the cascade.
## OpenAPI
````yaml patch /v1/workspaces/{workspaceId}/agents/{agentId}/variations/{variationId}/memory_layer_assignments/{id}
openapi: 3.1.0
info:
title: Cadenya API
description: API for the Cadenya Agent Runtime platform.
version: '1.0'
servers:
- url: https://api.cadenya.com
description: Production server
security:
- bearerAuth: []
tags:
- name: AIProviderKeyService
- name: APIKeyService
description: |-
Issue, rotate, disable, and revoke a workspace's API keys. Every key
belongs to exactly one workspace; the system-managed global account key is
managed via GlobalAPIKeyService instead.
- name: AccountService
description: >-
Manage the authenticated account. Accounts are the top-level
organizational
unit and contain one or more workspaces.
- name: AgentScheduleService
description: >-
Manage recurring schedules attached to agents. Schedules trigger
objectives
on a cadence defined by AgentScheduleSpec.Schedule.
- name: AgentService
description: >-
Manage AI agents within a workspace. Agents define AI behavior and tool
access.
- name: AgentVariationService
description: >-
Manage variations of an agent and their tool, sub-agent, and memory layer
assignments.
- name: GlobalAPIKeyService
description: |-
Manage the account's system-provisioned global API key. The global key is
the only key that spans every workspace; it is created by the system and
cannot be deleted, so the surface is retrieve, rotate, and the
disable/enable kill switch.
- name: MemoryService
description: >-
Manage memory layers and their entries. Layers are named containers that
can
be composed into an objective's memory cascade; entries are the keyed values
within a layer. System-managed layers (e.g., episodic layers created by the
runtime) cannot be mutated through this API.
- name: ModelService
description: |-
Manage LLM models available to a workspace. Models represent provider and
family pairs (e.g., "anthropic/claude-sonnet-4.6"). Workspaces are seeded
with the supported models and you can enable or disable each one.
- name: ObjectiveEventStreamsService
- name: ObjectiveService
- name: ProfilesService
description: |-
Operations on profiles, the account-level principals (users, API keys,
system) that authenticate against the API.
- name: SearchService
- name: TenantService
description: >-
Read and erase tenants and the subjects under them. Tenants and subjects
are
created by assertion — on objective creation or widget session mint — never
directly, so this service has no create or update: it exists to enumerate what
assertions have produced, and to destroy it on request.
- name: ToolService
description: >-
Manage tool sets and the tools they contain. Tool sets group related
tools,
and tools define specific capabilities available to agents.
When a tool set is managed, only API key actors can modify its tools; human
(profile) actors cannot.
- name: UploadService
description: |-
Issue short-lived presigned URLs for direct client-to-object-storage
uploads. Created uploads can be referenced by id when creating or updating
resources that accept binary content (e.g., MemoryEntry).
- name: WidgetService
description: |-
Manage embeddable chat widgets. A widget binds an agent to a globally
unique hostname with a per-widget origin allowlist; browsers reach it with
session tokens minted via WidgetSessionService.
- name: WidgetSessionService
description: >-
Mint and manage widget sessions. Session creation is server-to-server
only:
the customer's backend authenticates its visitor, asserts tenant/subject
context, attaches any per-visitor secrets, and receives a short-lived
bearer token the browser uses against the widget host.
- name: WorkspaceAdminService
description: >-
Administer workspaces across the account: create and archive workspaces
and
manage their membership. These operations are account-scoped and require the
admin role (a token whose profile holds the WorkOS admin role); they live
under /v1/account/workspaces rather than the workspace-scoped /v1/workspaces
tree so an admin can manage any workspace in the account, including ones they
are not themselves a member of.
- name: WorkspaceSecretService
- name: WorkspaceService
description: |-
Manage workspaces within an account. Workspaces provide organizational
grouping and isolation for resources such as agents, tools, and API keys.
This is the workspace-scoped, end-user surface. Administrative operations
(create / archive workspaces, manage members) live in WorkspaceAdminService
under /v1/account/workspaces and require the admin role.
paths:
/v1/workspaces/{workspaceId}/agents/{agentId}/variations/{variationId}/memory_layer_assignments/{id}:
patch:
tags:
- AgentVariationService
- Agent Variations
summary: Update a variation's memory layer assignment
description: Updates the position of a memory layer assignment on a variation.
operationId: AgentVariationService_UpdateAgentVariationMemoryLayer
parameters:
- name: workspaceId
in: path
description: Workspace ID.
required: true
schema:
type: string
example: workspace_01HXKD2E5NQM3T9AYWCF133E3Q
- name: agentId
in: path
description: >-
Agent ID. Accepts the canonical `agent_…` form or the
`external_id:` form.
required: true
schema:
example: agent_01HXKD2E5NQM3T9AYWCFMGWT9Y
type: string
- name: variationId
in: path
description: >-
Variation ID. Accepts the canonical `agentvar_…` form or the
`external_id:` form.
required: true
schema:
type: string
example: agentvar_01HXKD2E5NQM3T9AYWCF32BSPP
- name: id
in: path
required: true
schema:
type: string
example: avml_01HXKD2E5NQM3T9AYWCFX8AF59
requestBody:
content:
application/json:
schema:
$ref: '#/components/schemas/UpdateAgentVariationMemoryLayerRequest'
required: true
responses:
'200':
description: OK
content:
application/json:
schema:
$ref: '#/components/schemas/VariationMemoryLayerAssignment'
default:
description: Default error response
content:
application/json:
schema:
$ref: '#/components/schemas/Status'
x-codeSamples:
- lang: JavaScript
source: >-
import Cadenya from '@cadenya/cadenya';
const client = new Cadenya({
apiKey: process.env['CADENYA_API_KEY'], // This is the default and can be omitted
});
const variationMemoryLayerAssignment = await
client.agents.variations.updateMemoryLayer(
'agent_01HXKD2E5NQM3T9AYWCFMGWT9Y',
'agentvar_01HXKD2E5NQM3T9AYWCF32BSPP',
'avml_01HXKD2E5NQM3T9AYWCFX8AF59',
{ workspaceId: 'workspace_01HXKD2E5NQM3T9AYWCF133E3Q' },
);
console.log(variationMemoryLayerAssignment.id);
- lang: Python
source: >-
import os
from cadenya import Cadenya
client = Cadenya(
api_key=os.environ.get("CADENYA_API_KEY"), # This is the default and can be omitted
)
variation_memory_layer_assignment =
client.agents.variations.update_memory_layer(
agent_id="agent_01HXKD2E5NQM3T9AYWCFMGWT9Y",
variation_id="agentvar_01HXKD2E5NQM3T9AYWCF32BSPP",
id="avml_01HXKD2E5NQM3T9AYWCFX8AF59",
workspace_id="workspace_01HXKD2E5NQM3T9AYWCF133E3Q",
)
print(variation_memory_layer_assignment.id)
- lang: Go
source: "package main\n\nimport (\n\t\"context\"\n\t\"fmt\"\n\t\"go.cadenya.com/cadenya-go\"\n\t\"go.cadenya.com/cadenya-go/option\"\n)\n\nfunc main() {\n\tclient := cadenya.NewClient(\n\t\toption.WithAPIKey(\"My API Key\"),\n\t)\n\tvariationMemoryLayerAssignment, err := client.Agents.Variations.UpdateMemoryLayer(\n\t\tcontext.TODO(),\n\t\t\"agent_01HXKD2E5NQM3T9AYWCFMGWT9Y\",\n\t\t\"agentvar_01HXKD2E5NQM3T9AYWCF32BSPP\",\n\t\t\"avml_01HXKD2E5NQM3T9AYWCFX8AF59\",\n\t\tcadenya.AgentVariationUpdateMemoryLayerParams{\n\t\t\tWorkspaceID: cadenya.String(\"workspace_01HXKD2E5NQM3T9AYWCF133E3Q\"),\n\t\t},\n\t)\n\tif err != nil {\n\t\tpanic(err.Error())\n\t}\n\tfmt.Printf(\"%+v\\n\", variationMemoryLayerAssignment.ID)\n}\n"
- lang: Ruby
source: >-
require "cadenya"
cadenya = Cadenya::Client.new(api_key: "My API Key")
variation_memory_layer_assignment =
cadenya.agents.variations.update_memory_layer(
"agent_01HXKD2E5NQM3T9AYWCFMGWT9Y",
"agentvar_01HXKD2E5NQM3T9AYWCF32BSPP",
"avml_01HXKD2E5NQM3T9AYWCFX8AF59",
workspace_id: "workspace_01HXKD2E5NQM3T9AYWCF133E3Q"
)
puts(variation_memory_layer_assignment)
- lang: CLI
source: |-
cadenya agents:variations update-memory-layer \
--api-key 'My API Key' \
--workspace-id workspace_01HXKD2E5NQM3T9AYWCF133E3Q \
--agent-id agent_01HXKD2E5NQM3T9AYWCFMGWT9Y \
--variation-id agentvar_01HXKD2E5NQM3T9AYWCF32BSPP \
--id avml_01HXKD2E5NQM3T9AYWCFX8AF59
components:
schemas:
UpdateAgentVariationMemoryLayerRequest:
type: object
properties:
workspaceId:
readOnly: true
example: workspace_01HXKD2E5NQM3T9AYWCF133E3Q
type: string
description: Workspace ID.
agentId:
readOnly: true
example: agent_01HXKD2E5NQM3T9AYWCFMGWT9Y
type: string
description: >-
Agent ID. Accepts the canonical `agent_…` form or the
`external_id:` form.
variationId:
readOnly: true
example: agentvar_01HXKD2E5NQM3T9AYWCF32BSPP
type: string
description: >-
Variation ID. Accepts the canonical `agentvar_…` form or the
`external_id:` form.
id:
readOnly: true
example: avml_01HXKD2E5NQM3T9AYWCFX8AF59
type: string
position:
type: integer
description: New position. Only field currently updatable on an assignment.
format: int32
description: |-
Update an existing memory layer assignment. Only `position` is mutable.
A new position that collides with another assignment on the same variation
is rejected with InvalidArgument.
VariationMemoryLayerAssignment:
type: object
properties:
id:
readOnly: true
example: avml_01HXKD2E5NQM3T9AYWCFX8AF59
type: string
description: |-
Assignment row id — handle for removing the assignment. Distinct
from the referenced memory layer's id.
memoryLayer:
allOf:
- $ref: '#/components/schemas/BareMetadata'
description: The attached memory layer.
position:
type: integer
description: |-
Position in the variation's baseline cascade. Position is
specificity, CSS-style: a LOWER position is more specific and is
consulted first; the highest-position assignment is the most
general fallback. 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.
format: int32
description: |-
VariationMemoryLayerAssignment attaches a single MemoryLayer to a
variation at a given position in the variation's baseline memory
cascade. A variation has at most one assignment per memory_layer_id.
Variations only support whole-layer attachments — entry pinning is an
objective-level capability.
Status:
type: object
properties:
code:
type: integer
description: >-
The status code, which should be an enum value of
[google.rpc.Code][google.rpc.Code].
format: int32
message:
type: string
description: >-
A developer-facing error message, which should be in English. Any
user-facing error message should be localized and sent in the
[google.rpc.Status.details][google.rpc.Status.details] field, or
localized by the client.
details:
type: array
items:
$ref: '#/components/schemas/GoogleProtobufAny'
description: >-
A list of messages that carry the error details. There is a common
set of message types for APIs to use.
description: >-
The `Status` type defines a logical error model that is suitable for
different programming environments, including REST APIs and RPC APIs. It
is used by [gRPC](https://github.com/grpc). Each `Status` message
contains three pieces of data: error code, error message, and error
details. You can find out more about this error model and how to work
with it in the [API Design
Guide](https://cloud.google.com/apis/design/errors).
BareMetadata:
type: object
properties:
id:
readOnly: true
type: string
name:
readOnly: true
type: string
description: >-
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).
description: |-
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.
GoogleProtobufAny:
type: object
properties:
'@type':
type: string
description: The type of the serialized message.
additionalProperties: true
description: >-
Contains an arbitrary serialized message along with a @type that
describes the type of the serialized message.
securitySchemes:
bearerAuth:
type: http
scheme: bearer
bearerFormat: JWT
````