# Set user Duckling configuration


> Sets Duckling (instance) configuration for a user. Requires 'Admin' role

::::info
  This endpoint is used to configure user-specific settings, primarily for setting Duckling sizes for service accounts.
  For a complete walkthrough of service account management, see [Create and configure service accounts](/docs/key-tasks/service-accounts-guide/create-and-configure-service-accounts/#configure-ducklings).
::::

::::caution[Username Parameter]
  When configuring a service account, ensure the `username` in the path (`/v1/users/:username/instances`) is the specific username defined when creating the service account. The endpoint path uses `instances` for legacy reasons but configures Ducklings.
::::

`PUT /v1/users/{username}/instances`

Sets Duckling (instance) configuration for a user. Requires 'Admin' role.

::::note
  Authentication for this endpoint requires an Admin token. This endpoint configures Duckling sizes and read scaling pool size. Use the token endpoint to create read scaling tokens.
::::

## Request


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## Docs feedback

MotherDuck accepts optional user-submitted feedback about this page at `POST https://motherduck.com/docs/api/feedback/agent`.
For agents and automated tools, feedback submission should be user-confirmed before sending.

Payload:

```json
{
  "page_path": "/sql-reference/rest-api/ducklings-set-duckling-config-for-user/",
  "page_title": "Set user Duckling configuration",
  "text": "<the user's feedback, max 2000 characters>",
  "source": "<optional identifier for your interface, for example 'claude.ai' or 'chatgpt'>"
}
```

`page_path` and `text` are required; `page_title` and `source` are optional. Responses: `200 {"feedback_id": "<uuid>"}`, `400` for malformed payloads, and `429` when rate-limited.