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

# v2.1.6

> Helm v2.1.6 changelog - 2026-04-24

<Update label="Bifrost Helm" description="v2.1.6">
  ## Changelog

  * Includes unreleased `2.1.5` changes
  * Built-in plugin versioning for DB-backed deployments:
    * Added `version` field support for built-in plugins.
    * Added default `version: 1` for built-in plugins in `values.yaml` (`telemetry`, `logging`, `governance`, `maxim`, `semanticCache`, `otel`, `datadog`).
    * Updated `_helpers.tpl` to include plugin `version` in rendered config when set (cast as integer).
  * Updated StatefulSet PVC template labels to be immutable-safe:
    * `spec.volumeClaimTemplates.metadata.labels` now uses stable selector labels (without chart/app version labels).
  * Governance schema and validation updates:
    * Added `governance.budgets[].virtual_key_id` support.
    * Removed stale `budget_id` references from virtual keys and provider configs in templates/tests.
    * `validate-helm-config-fields.sh` assertions were updated accordingly.
  * Query/schema compatibility updates:
    * Tightened `query` validation in `values.schema.json` and `config.schema.json` to valid RuleGroupType shape (`null` or `{ combinator, rules }`).
  * Config/input alias support updates:
    * Added support for `env.*` references in proxy/TLS fields (`ca_cert_pem`, `url`, `username`, `password`).
    * Added `provider_key_name` alias for routing targets and pricing overrides (resolved to `key_id` at config load time).
  * MCP config improvements:
    * Added Go duration string support for `mcp.toolSyncInterval` (legacy numeric nanoseconds still supported).
    * Added hash-based MCP client config reconciliation for DB-backed config store updates.
  * Upgrade impact:
    * Existing SQLite StatefulSets created from older chart templates may require a one-time StatefulSet recreation during upgrade because `spec.volumeClaimTemplates` is immutable in Kubernetes.
  * Migration notes (only if upgrade fails with StatefulSet immutable-field error):
    1. Identify StatefulSet name and namespace for your Helm release.
    2. Delete only the StatefulSet while preserving dependents:
       * `kubectl delete statefulset <statefulset-name> -n <namespace> --cascade=orphan`
    3. Run Helm upgrade:
       * `helm upgrade <release-name> bifrost/bifrost -n <namespace> -f <values-file> --set image.tag=<tag>`
    4. If needed, re-apply/recreate the StatefulSet from the upgraded chart manifests.
    5. Verify PVCs are preserved and pods become healthy:
       * `kubectl get pvc -n <namespace>`
       * `kubectl get pods -n <namespace>`
</Update>