> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zerodrift.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Delete Custom Rule

> Permanently delete a customer-owned custom rule

Permanently delete a customer-owned custom rule and remove its sole
policy-import reference. Only `cust_*` definitions owned by the
authenticated customer can be deleted; YAML/system pack rules are rejected.

Deletion is rejected while the policy is pending review, training is in
progress, a trained adapter still references the policy, or multiple policy
imports reference the rule.

Requires a full-access API key.

## Path Parameters

<ParamField path="rule_id" type="string" required>
  Custom rule identifier (must be a `cust_*` definition)
</ParamField>

## Response

Returns `204 No Content` with no body on success.

## Errors

| Status | Meaning |
| - | - |
| `400` | Rule is not a customer-owned `cust_*` definition |
| `403` | Forbidden — full-access API key required |
| `404` | Custom rule not found |
| `409` | Rule has conflicting policy or training references, or changed concurrently |