invoke-ai/InvokeAI · warning · HTTPException

Cannot unlink a model from itself.

Error message

Cannot unlink a model from itself.

What it means

HTTP 400 raised by DELETE /models/relationships when model_key_1 equals model_key_2 in the request body. A model cannot be unlinked from itself; the endpoint validates this before touching the service layer.

Source

Thrown at invokeai/app/api/routers/model_relationships.py:159

        404: {"description": "The relationship does not exist"},
        422: {"description": "Validation error"},
        500: {"description": "Internal server error"},
    },
    summary="Remove Model Relationship",
    description="Removes a **bidirectional** relationship between two models. The relationship must already exist.",
)
def remove_model_relationship(
    current_user: AdminUserOrDefault,
    req: ModelRelationshipCreateRequest = Body(..., description="The model keys to disconnect"),
) -> None:
    """
    Removes a bidirectional relationship between two model keys.

    - Raises 400 if attempting to unlink a model from itself.
    - Raises 404 if the relationship was not found.
    """
    if req.model_key_1 == req.model_key_2:
        raise HTTPException(status_code=400, detail="Cannot unlink a model from itself.")

    try:
        ApiDependencies.invoker.services.model_relationships.remove_model_relationship(
            req.model_key_1,
            req.model_key_2,
        )
    except ValueError as e:
        raise HTTPException(status_code=404, detail=str(e))


@model_relationships_router.post(
    "/batch",
    operation_id="get_related_models_batch",
    response_model=List[str],
    responses={
        200: {
            "description": "Related model keys retrieved successfully",
            "content": {

View on GitHub (pinned to 0b6a024f2f)

Solutions

1. Guard that model_key_1 !== model_key_2 before issuing the DELETE
2. Filter out degenerate pairs when generating unlink requests from stored relationships
3. Fix the UI/form sending one key in both fields

Example fix

// before
await api.removeRelationship({ model_key_1: k, model_key_2: k });
// after
if (k1 !== k2) await api.removeRelationship({ model_key_1: k1, model_key_2: k2 });

if (req.model_key_1 === req.model_key_2) {
  throw new Error('Cannot unlink a model from itself');
}

try {
  await api.removeRelationship(req);
} catch (e) {
  if (e.status === 400 && e.body?.detail === 'Cannot unlink a model from itself.') throw new Error('self-pair in payload');
  throw e;
}

When it happens

Trigger: DELETE /api/v1/models/relationships with identical keys in both fields of the request body — usually the same client bug that would have produced the self-relate 400 at add time.

Common situations: Symmetric cleanup scripts calling delete for every pair including degenerate pairs; stale client state passing one key twice.

Related errors

• Cannot relate a model to itself.
• No external provider config fields provided
• str(e)
• str(e) (ValueError from user service update, e.g. LastAdmini
• Current password is required to set a new password

AI-assisted analysis of invoke-ai/InvokeAI@0b6a024f2f (2026-08-29). Data as JSON: /api/errors/a1e8b55b4553e698. Report an issue: GitHub.