diff --git a/.devcontainer/Dockerfile b/.devcontainer/Dockerfile
index 988ce27a..9a3f0f14 100644
--- a/.devcontainer/Dockerfile
+++ b/.devcontainer/Dockerfile
@@ -91,7 +91,8 @@ RUN mkdir -p /usr/local/lib/hermes-agent \
     && cd /tmp/hermes \
     && python -m venv /usr/local/lib/hermes-agent/venv \
     && /usr/local/lib/hermes-agent/venv/bin/pip install --no-cache-dir . \
-    && /usr/local/lib/hermes-agent/venv/bin/pip install --no-cache-dir "agent-client-protocol>=0.9.0,<1.0" \
+    && /usr/local/lib/hermes-agent/venv/bin/pip install --no-cache-dir ".[acp]" \
+    && /usr/local/lib/hermes-agent/venv/bin/hermes acp --check \
     && rm -rf /tmp/hermes
 
 # ── Final stage ────────────────────────────────────────────────────────
@@ -210,8 +211,12 @@ RUN ln -sf /usr/local/lib/hermes-agent/venv/bin/hermes /usr/local/bin/hermes
 # ── Ensure hermes venv is world-readable ───────────────────────────────
 # FHS root layout places the venv at /usr/local/lib/hermes-agent/venv/.
 # Some sub-directories may be mode 700 (root-only).  Make them traversable
-# so the vscode user can exec hermes and its bundled Python.
+# so the vscode user can exec hermes and its bundled Python.  The venv is
+# also made group/other-WRITABLE so the VS Code extension's ACP dependency
+# repair flow (pip install into the venv as the vscode user) can succeed
+# without sudo — this is a devcontainer, not a hardened prod image.
 RUN chmod -R a+rX /usr/local/lib/hermes-agent 2>/dev/null || true \
+    && chmod -R a+rwX /usr/local/lib/hermes-agent/venv 2>/dev/null || true \
     && chmod -R a+rX /usr/local/lib/nodejs 2>/dev/null || true
 
 # ── Make claude CLI accessible if installed to /root ───────────────────
diff --git a/.devcontainer/self-check.sh b/.devcontainer/self-check.sh
index d8ceb70c..0d1d1613 100755
--- a/.devcontainer/self-check.sh
+++ b/.devcontainer/self-check.sh
@@ -237,6 +237,17 @@ if ! should_skip "hermes"; then
     _fail "Config" "no config at ${HERMES_CONFIG}"
     json_add "hermes:config" "fail" "hermes config file not found" "{}"
   fi
+
+  # ACP adapter — the VS Code extension's chat backend. A broken adapter
+  # (e.g. agent-client-protocol version drift) shows up as "ACP connection
+  # closed" in the extension and is otherwise silent.
+  if hermes acp --check >/dev/null 2>&1; then
+    _ok "ACP Adapter" "hermes acp --check OK"
+    json_add "hermes:acp" "ok" "ACP adapter imports and protocol deps OK" "{}"
+  else
+    _fail "ACP Adapter" "hermes acp --check failed (VS Code extension won't connect)"
+    json_add "hermes:acp" "fail" "hermes acp --check failed" "{}"
+  fi
 else
   echo "   (skipped)"
 fi
diff --git a/.github/workflows/devcontainer-ci.yml b/.github/workflows/devcontainer-ci.yml
index a4bdeec8..d4361fb7 100644
--- a/.github/workflows/devcontainer-ci.yml
+++ b/.github/workflows/devcontainer-ci.yml
@@ -7,7 +7,7 @@ on:
       - '.devcontainer/**'
       - '!.devcontainer/screen-shot.png'
   pull_request:
-    branches: [main]
+    branches: [main, dockerizeation2]
     paths:
       - '.devcontainer/**'
       - '!.devcontainer/screen-shot.png'
@@ -111,6 +111,7 @@ jobs:
             check "zsh installed"             "command -v zsh"
             check "ripgrep installed"         "command -v rg"
             check "entrypoint.sh exists"      "[ -x /usr/local/bin/entrypoint.sh ]"
+            check "hermes ACP adapter works"   "hermes acp --check"
 
             echo ""
             echo "=== Results: $PASS passed, $FAIL failed ==="