diff --git a/.gitea/workflows/continuous-synth-e2e.yml b/.gitea/workflows/continuous-synth-e2e.yml
index 569a11197..e26c8577e 100644
--- a/.gitea/workflows/continuous-synth-e2e.yml
+++ b/.gitea/workflows/continuous-synth-e2e.yml
@@ -166,6 +166,10 @@ jobs:
       # canary path. The script picks the right blob shape based on
       # which key is non-empty.
       E2E_OPENAI_API_KEY: ${{ secrets.MOLECULE_STAGING_OPENAI_API_KEY }}
+      # google-adk canary path — AI-Studio key (config model
+      # google_genai:gemini-2.5-pro). PROD disallows API keys (Vertex+ADC);
+      # the keyed path is CI-only. Dispatch with E2E_RUNTIME=google-adk.
+      E2E_GOOGLE_API_KEY: ${{ secrets.MOLECULE_STAGING_GOOGLE_API_KEY }}
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
@@ -217,6 +221,10 @@ jobs:
               required_secret_name="MOLECULE_STAGING_OPENAI_API_KEY"
               required_secret_value="${E2E_OPENAI_API_KEY:-}"
               ;;
+            google-adk)
+              required_secret_name="MOLECULE_STAGING_GOOGLE_API_KEY"
+              required_secret_value="${E2E_GOOGLE_API_KEY:-}"
+              ;;
             *)
               echo "::warning::Unknown E2E_RUNTIME='${E2E_RUNTIME}' — skipping LLM-key check"
               required_secret_name=""
diff --git a/.gitea/workflows/e2e-staging-saas.yml b/.gitea/workflows/e2e-staging-saas.yml
index 92db50363..56202e98d 100644
--- a/.gitea/workflows/e2e-staging-saas.yml
+++ b/.gitea/workflows/e2e-staging-saas.yml
@@ -157,13 +157,18 @@ jobs:
       # E2E_RUNTIME=hermes or =codex via workflow_dispatch can still
       # exercise the OpenAI path.
       E2E_OPENAI_API_KEY: ${{ secrets.MOLECULE_STAGING_OPENAI_API_KEY }}
+      # google-adk (operator-dispatched only) auths Gemini with an
+      # AI-Studio key. Org policy disallows API keys in PROD (Vertex+ADC
+      # there); CI uses the keyed AI-Studio path with config model
+      # google_genai:gemini-2.5-pro. Vertex remains the supported prod path.
+      E2E_GOOGLE_API_KEY: ${{ secrets.MOLECULE_STAGING_GOOGLE_API_KEY }}
       E2E_RUNTIME: ${{ github.event.inputs.runtime || 'claude-code' }}
       # Pin the model when running on the default claude-code path —
       # the per-runtime default ("sonnet") routes to direct Anthropic
       # and defeats the cost saving. Operators can override via the
       # workflow_dispatch flow (no input wired here yet — runtime
       # override is enough for ad-hoc).
-      E2E_MODEL_SLUG: ${{ github.event.inputs.runtime == 'hermes' && 'openai/gpt-4o' || github.event.inputs.runtime == 'codex' && 'openai/gpt-4o' || 'MiniMax-M2' }}
+      E2E_MODEL_SLUG: ${{ github.event.inputs.runtime == 'hermes' && 'openai/gpt-4o' || github.event.inputs.runtime == 'codex' && 'openai/gpt-4o' || github.event.inputs.runtime == 'google-adk' && 'google_genai:gemini-2.5-pro' || 'MiniMax-M2' }}
       E2E_RUN_ID: "${{ github.run_id }}-${{ github.run_attempt }}"
       E2E_KEEP_ORG: ${{ github.event.inputs.keep_org && '1' || '0' }}
 
@@ -212,6 +217,10 @@ jobs:
               required_secret_name="MOLECULE_STAGING_OPENAI_API_KEY"
               required_secret_value="${E2E_OPENAI_API_KEY:-}"
               ;;
+            google-adk)
+              required_secret_name="MOLECULE_STAGING_GOOGLE_API_KEY"
+              required_secret_value="${E2E_GOOGLE_API_KEY:-}"
+              ;;
             *)
               echo "::warning::Unknown E2E_RUNTIME='${E2E_RUNTIME}' — skipping LLM-key check"
               required_secret_name=""
diff --git a/scripts/test-all-runtimes-a2a-e2e.sh b/scripts/test-all-runtimes-a2a-e2e.sh
index 013ceead3..67292eb05 100755
--- a/scripts/test-all-runtimes-a2a-e2e.sh
+++ b/scripts/test-all-runtimes-a2a-e2e.sh
@@ -1,12 +1,13 @@
 #!/usr/bin/env bash
-# E2E test: A2A round-trip parity across all four runtimes.
+# E2E test: A2A round-trip parity across all five runtimes.
 #
-# Validates that for each of {claude-code, hermes, codex, openclaw}:
+# Validates that for each of {claude-code, hermes, codex, openclaw, google-adk}:
 #   1. A workspace can be provisioned + brought online
 #   2. The adapter responds to A2A message/send
 #   3. The reply contains expected content (echo of the prompt)
 #   4. A SECOND message preserves session state where the runtime
-#      supports it (currently: hermes via plugin path)
+#      supports it (currently: hermes via plugin path; google-adk via
+#      ADK InMemorySessionService keyed on A2A context_id)
 #
 # Targets a SaaS tenant subdomain. Provisions workspaces in the calling
 # tenant, runs the round-trip, deletes them on success.
@@ -16,6 +17,10 @@
 #       (e.g. https://demo-tenant.staging.moleculesai.app)
 #   - $OPENROUTER_API_KEY (or $HERMES_API_KEY) for non-claude runtimes
 #   - $OPENAI_API_KEY for claude-code peer
+#   - $GOOGLE_API_KEY (AI Studio) for google-adk — the org disallows API
+#       keys in PROD (Vertex+ADC there), but CI auths Gemini with an
+#       AI-Studio key (config model google_genai:gemini-2.5-pro). Vertex
+#       stays supported; this is the keyed CI path only.
 #   - SaaS edge requires Origin header — see auto-memory
 #       reference_saas_waf_origin_header.md
 #
@@ -24,12 +29,13 @@
 #       ./scripts/test-all-runtimes-a2a-e2e.sh
 #
 # Skip individual runtimes:
-#   SKIP_HERMES=1 SKIP_OPENCLAW=1 ./scripts/test-all-runtimes-a2a-e2e.sh
+#   SKIP_HERMES=1 SKIP_OPENCLAW=1 SKIP_GOOGLE_ADK=1 ./scripts/test-all-runtimes-a2a-e2e.sh
 set -euo pipefail
 
 PLATFORM="${PLATFORM:-${1:-http://localhost:8080}}"
 HERMES_PROVIDER_KEY="${OPENROUTER_API_KEY:-${HERMES_API_KEY:-}}"
 PEER_OPENAI_KEY="${OPENAI_API_KEY:-}"
+GOOGLE_ADK_KEY="${GOOGLE_API_KEY:-}"
 # SaaS auth chain — TENANT_ADMIN_TOKEN + TENANT_ORG_ID required when
 # hitting *.moleculesai.app (per-tenant ADMIN_TOKEN, NOT
 # CP_ADMIN_API_TOKEN). Optional for localhost.
@@ -48,6 +54,10 @@ if [ -z "$HERMES_PROVIDER_KEY" ] && [ -z "${SKIP_HERMES:-}${SKIP_CODEX:-}${SKIP_
   echo "FAIL: set OPENROUTER_API_KEY or HERMES_API_KEY for non-claude runtimes"
   exit 2
 fi
+if [ -z "$GOOGLE_ADK_KEY" ] && [ -z "${SKIP_GOOGLE_ADK:-}" ]; then
+  echo "FAIL: set GOOGLE_API_KEY (AI Studio) for google-adk, or SKIP_GOOGLE_ADK=1"
+  exit 2
+fi
 
 PASS=0
 FAIL=0
@@ -143,7 +153,7 @@ echo "=========================================="
 echo ""
 
 # -------------------------------------------------------
-# 1. Provision the four runtimes (skip via SKIP_* flags)
+# 1. Provision the five runtimes (skip via SKIP_* flags)
 # -------------------------------------------------------
 echo "--- 1. Provision workspaces ---"
 if [ -z "${SKIP_CLAUDE_CODE:-}" ]; then
@@ -162,6 +172,10 @@ if [ -z "${SKIP_OPENCLAW:-}" ]; then
   WS_IDS[openclaw]=$(provision "ParityOpenClaw" "openclaw" "openclaw peer")
   echo "  openclaw:    ${WS_IDS[openclaw]}"
 fi
+if [ -z "${SKIP_GOOGLE_ADK:-}" ]; then
+  WS_IDS[google-adk]=$(provision "ParityGoogleADK" "google-adk" "google-adk peer")
+  echo "  google-adk:  ${WS_IDS[google-adk]}"
+fi
 
 # -------------------------------------------------------
 # 2. Set provider keys
@@ -177,6 +191,12 @@ if [ -n "${WS_IDS[claude-code]:-}" ] && [ -n "$PEER_OPENAI_KEY" ]; then
   set_secret "${WS_IDS[claude-code]}" "OPENAI_API_KEY" "$PEER_OPENAI_KEY"
   echo "  claude-code: OPENAI_API_KEY set"
 fi
+if [ -n "${WS_IDS[google-adk]:-}" ] && [ -n "$GOOGLE_ADK_KEY" ]; then
+  # AI-Studio path: the adapter reads GOOGLE_API_KEY natively when the
+  # config model is google_genai:gemini-2.5-pro (see _routing.resolve_model).
+  set_secret "${WS_IDS[google-adk]}" "GOOGLE_API_KEY" "$GOOGLE_ADK_KEY"
+  echo "  google-adk:  GOOGLE_API_KEY set"
+fi
 
 # -------------------------------------------------------
 # 3. Wait for online
@@ -188,6 +208,9 @@ for runtime in "${!WS_IDS[@]}"; do
   [ -z "$id" ] && continue
   max=60
   [ "$runtime" = "hermes" ] && max=120
+  # google-adk's first cold boot pulls a large fresh ADK image — give it
+  # a hermes-class window so a slow first pull doesn't read as "failed".
+  [ "$runtime" = "google-adk" ] && max=180
   if wait_online "$id" "$runtime" "$max"; then
     check "$runtime online" "ok" "ok"
   else
@@ -200,7 +223,7 @@ done
 # -------------------------------------------------------
 echo ""
 echo "--- 4. A2A round-trip (first message) ---"
-for runtime in claude-code hermes codex openclaw; do
+for runtime in claude-code hermes codex openclaw google-adk; do
   id="${WS_IDS[$runtime]:-}"
   [ -z "$id" ] && continue
   reply=$(a2a_send "$id" "Reply with just the word OK so we know you got this.")
@@ -213,7 +236,7 @@ done
 # -------------------------------------------------------
 echo ""
 echo "--- 5. Session continuity (second message recalls first) ---"
-for runtime in claude-code hermes codex openclaw; do
+for runtime in claude-code hermes codex openclaw google-adk; do
   id="${WS_IDS[$runtime]:-}"
   [ -z "$id" ] && continue
   # Set up: tell the agent a name.