Envoy AI Gateway v0.6.x

✨ New Features​

🔗 API Updates​

• Core CRDs promoted to aigateway.envoyproxy.io/v1beta1: AIGatewayRoute, AIServiceBackend, BackendSecurityPolicy, GatewayConfig, and MCPRoute are now served at v1beta1, signaling that the core API and MCP routing surface are stable enough for production use. v1alpha1 versions remain registered with deprecation warnings so existing manifests continue to apply during the upgrade window.
• MCPRouteBackendRef.forwardHeaders: New per-backend list of headers to forward, with optional rename. Replaces the need for a single route-wide header forwarding rule when backends expect different headers.
• MCPRouteOAuth.claimToHeaders: Configure which verified JWT claims should be projected into outbound headers to MCP backends.
• MCPToolFilter.exclude / excludeRegex: Tool selectors now support exclusion alongside inclusion, with both literal and regex forms.
• LLMRequestCostType.ReasoningToken: New cost type for thinking-token usage, complementing the existing input, output, and cache cost types.
• GatewayConfig.spec.globalLLMRequestCosts: Fleet-wide cost defaults that individual AIGatewayRoute.spec.llmRequestCosts entries can override.
• Preview: QuotaPolicy API (v1alpha1, no runtime enforcement yet): New CRD surface for declaring upstream-provider quota policies, laying the groundwork for quota-aware routing. Currently API-only — no controller reconciliation or enforcement is wired up. Track it for future releases; do not rely on it as a working feature today.

⚠️ Breaking Changes​

• AIGatewayRoute.spec.filterConfig removed: The filterConfig field on AIGatewayRoute has been removed. Move external-processor configuration (resources, env vars, image overrides) to a GatewayConfig resource referenced from the Gateway via the aigateway.envoyproxy.io/gateway-config annotation. v0.5 deprecated the resources subfield with a pointer to GatewayConfig; v0.6 removes the entire filterConfig struct, so anything still set there must move now.
• VersionedAPISchema.version no longer acts as an endpoint prefix for OpenAI-schema backends: The legacy behavior deprecated in v0.5 — using the version field as a path prefix for OpenAI-schema backends — has been removed. Use the dedicated prefix field instead (e.g. prefix: /v1beta/openai for Gemini's OpenAI-compatible API, prefix: /compatibility/v1 for Cohere).

🐛 Bug Fixes​

• Webhook cache race during extProc injection: Fixes a race where freshly applied AIGatewayRoute resources could miss extProc injection on first reconcile because the conversion webhook read from a stale cache. Scripted apply-then-curl tests should see fewer flakes.
• Field ownership preserved on updates: Controllers no longer claim ownership of fields they don't manage during updates. If you co-deploy the AI Gateway controller alongside other operators that touch adjacent fields (e.g. service mesh injectors, policy controllers), expect fewer reconcile churn loops on shared resources.
• Orphan cleanup for MCPRoute backendrefs: Resources tied to MCPRoute backend references are now cleaned up when the route or reference is removed, fixing a leak that could leave stale config in the cluster.
• Standalone Envoy startup failures surfaced by aigw: aigw now reports standalone Envoy startup failures cleanly instead of hanging or printing an unhelpful trace, making local dev and CI loops much faster to diagnose.
• Bedrock Titan embeddings dataplane route: Restored the Envoy route for Titan embeddings in dataplane tests so Titan workloads exercise the full pipeline.
• Hardened bearer token parsing: Malformed Authorization: Bearer headers used to panic the MCP subject extractor; they now return a clean auth failure and the request falls through to the standard auth failure path.
• Request context propagation in PostTranslateModify: Kubernetes client calls inside PostTranslateModify now honor request cancellation and deadlines, reducing stuck reconciles when the parent request is canceled.
• Case-sensitive JSON marshalling and unmarshalling: JSON encoding now consistently honors case, fixing subtle mismatches when round-tripping fields whose names differ only in case (visible previously as occasional 400s on certain provider payloads).
• Secret rotation propagates to MCPRoute: Updates to a Secret referenced by an MCPBackendRef are now reflected in the live configuration, matching how BackendSecurityPolicy already handled secret updates. Operators rotating MCP backend credentials no longer need to bounce the route.
• MCP proxy handles compressed Accept-Encoding from upstreams: The MCP proxy now correctly handles compressed Accept-Encoding values from upstream requests, fixing failures when MCP backends advertise gzip or other compression schemes.
• aigw standalone accepts IP addresses for endpoints: In standalone mode, aigw previously assumed endpoints were hostnames; you can now point OpenAI and MCP env config at IP addresses (e.g. 127.0.0.1), making local dev against loopback addresses work.

📖 Upgrade Guidance​

Migrating from filterConfig to GatewayConfig​

The filterConfig field on AIGatewayRoute has been removed in v0.6. If you previously configured the external processor (resources, environment variables, image overrides) via filterConfig on individual routes, move that configuration to a GatewayConfig resource and reference it from the Gateway.

Before (v0.5):

apiVersion: aigateway.envoyproxy.io/v1alpha1
kind: AIGatewayRoute
metadata:
  name: my-route
spec:
  filterConfig:
    externalProcessor:
      resources:
        requests:
          cpu: "100m"
          memory: "128Mi"

After (v0.6):

apiVersion: aigateway.envoyproxy.io/v1beta1
kind: GatewayConfig
metadata:
  name: my-gateway-config
  namespace: default
spec:
  extProc:
    kubernetes:
      resources:
        requests:
          cpu: "100m"
          memory: "128Mi"
---
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: ai-gateway
  annotations:
    aigateway.envoyproxy.io/gateway-config: my-gateway-config

Migrating VersionedAPISchema.version to prefix​

The deprecated v0.5 behavior of using VersionedAPISchema.version as an endpoint path prefix for OpenAI-schema backends has been removed in v0.6. Use the dedicated prefix field instead.

Before (v0.5):

schema:
  name: OpenAI
  version: /v1beta/openai   # legacy: version field overloaded as path prefix

After (v0.6):

schema:
  name: OpenAI
  prefix: /v1beta/openai    # explicit prefix field

Adopting v1beta1 APIs​

AIGatewayRoute, AIServiceBackend, BackendSecurityPolicy, GatewayConfig, and MCPRoute are now served at aigateway.envoyproxy.io/v1beta1. Existing v1alpha1 manifests continue to work via conversion, but new manifests should target v1beta1 directly:

apiVersion: aigateway.envoyproxy.io/v1beta1
kind: AIGatewayRoute

Switching GCP backends to Workload Identity​

If you're running on GKE, drop static service-account keys and let the gateway pick up Application Default Credentials. Configure your BackendSecurityPolicy for GCP with the appropriate workload identity binding on the controller's service account; no serviceAccountJSON secret is required.

📦 Dependencies Versions​

⏩ Patch Releases​

🙏 Acknowledgements​

We extend our gratitude to all contributors who made this release possible. Special thanks to:

• The growing community of adopters for their valuable feedback and production insights
• Everyone who reported bugs, submitted PRs, and participated in design discussions
• The Envoy Gateway team for their continued collaboration

🔮 What's Next​

We're already working on features for future releases:

• Quota-aware routing — building on the new backend quota policy API to route around rate-limited upstreams automatically
• Deeper MCP authorization — finer-grained policy across tools, resources, and prompts
• Expanded provider coverage — additional embeddings, audio, and image generation backends across cloud providers
• More efficient large-context handling — continued improvements to streaming, memory use, and tracing for long-context workloads