diff --git a/scripts/install/install-editor-extension.sh b/scripts/install/install-editor-extension.sh
new file mode 100755
index 0000000000..dfe34ec6cb
--- /dev/null
+++ b/scripts/install/install-editor-extension.sh
@@ -0,0 +1,654 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+EXTENSION_ID="openai.chatgpt"
+CURSOR_BIN="${CODEX_CURSOR_BIN:-}"
+CODE_BIN="${CODEX_CODE_BIN:-}"
+CURSOR_DB="${CODEX_CURSOR_DB:-}"
+BACKUP_DIR="${CODEX_CURSOR_BACKUP_DIR:-}"
+PYTHON_BIN="${CODEX_PYTHON_BIN:-}"
+
+HAD_ERROR=0
+UPDATED_CURSOR_STATE=0
+
+step() {
+  printf '==> %s\n' "$1"
+}
+
+die() {
+  printf '%s\n' "$1" >&2
+  exit 1
+}
+
+default_cursor_db_path() {
+  case "$(uname -s)" in
+    Darwin)
+      printf '%s\n' "${HOME}/Library/Application Support/Cursor/User/globalStorage/state.vscdb"
+      ;;
+    Linux)
+      if [ -n "${XDG_CONFIG_HOME:-}" ]; then
+        printf '%s\n' "${XDG_CONFIG_HOME}/Cursor/User/globalStorage/state.vscdb"
+      else
+        printf '%s\n' "${HOME}/.config/Cursor/User/globalStorage/state.vscdb"
+      fi
+      ;;
+  esac
+}
+
+find_editor_bin() {
+  local explicit_path="$1"
+  local cli_name="$2"
+  shift 2
+
+  if [ -n "$explicit_path" ]; then
+    [ -x "$explicit_path" ] || die "Editor CLI is not executable: $explicit_path"
+    printf '%s\n' "$explicit_path"
+    return
+  fi
+
+  if command -v "$cli_name" >/dev/null 2>&1; then
+    command -v "$cli_name"
+    return
+  fi
+
+  local candidate_path
+  for candidate_path in "$@"; do
+    if [ -n "$candidate_path" ] && [ -x "$candidate_path" ]; then
+      printf '%s\n' "$candidate_path"
+      return
+    fi
+  done
+}
+
+find_python_bin() {
+  local explicit_path="$1"
+  shift
+
+  if [ -n "$explicit_path" ]; then
+    [ -x "$explicit_path" ] || die "Python is not executable: $explicit_path"
+    printf '%s\n' "$explicit_path"
+    return
+  fi
+
+  if command -v python3 >/dev/null 2>&1; then
+    command -v python3
+    return
+  fi
+
+  local candidate_path
+  for candidate_path in "$@"; do
+    if [ -n "$candidate_path" ] && [ -x "$candidate_path" ]; then
+      printf '%s\n' "$candidate_path"
+      return
+    fi
+  done
+}
+
+python_can_update_cursor_state() {
+  local python_bin="$1"
+  "$python_bin" -c 'import json, sqlite3' >/dev/null 2>&1
+}
+
+install_extension() {
+  local editor_name="$1"
+  local editor_bin="$2"
+
+  step "Installing ${EXTENSION_ID} into ${editor_name}"
+  "$editor_bin" --install-extension "$EXTENSION_ID" --force
+}
+
+process_running() {
+  local process_name="$1"
+  pgrep -ix "$process_name" >/dev/null 2>&1
+}
+
+darwin_app_running() {
+  local app_name="$1"
+  [ "$(uname -s)" = "Darwin" ] || return 1
+  command -v osascript >/dev/null 2>&1 || return 1
+  [ "$(osascript -e "application \"${app_name}\" is running" 2>/dev/null || printf 'false')" = "true" ]
+}
+
+wait_for_shutdown() {
+  local app_name="$1"
+  shift
+  local process_names=("$@")
+  local timeout_seconds=20
+  local second=0
+
+  while [ "$second" -lt "$timeout_seconds" ]; do
+    local app_stopped=1
+    local processes_stopped=1
+    local process_name
+
+    if [ -n "$app_name" ] && darwin_app_running "$app_name"; then
+      app_stopped=0
+    fi
+
+    for process_name in "${process_names[@]}"; do
+      if process_running "$process_name"; then
+        processes_stopped=0
+        break
+      fi
+    done
+
+    if [ "$app_stopped" -eq 1 ] && [ "$processes_stopped" -eq 1 ]; then
+      return 0
+    fi
+
+    sleep 1
+    second=$((second + 1))
+  done
+
+  return 1
+}
+
+quit_app_if_running() {
+  local editor_name="$1"
+  shift
+
+  local app_name=""
+  local process_names=()
+  while [ "$#" -gt 0 ]; do
+    case "$1" in
+      --app-name)
+        app_name="$2"
+        shift 2
+        ;;
+      *)
+        process_names+=("$1")
+        shift
+        ;;
+    esac
+  done
+
+  local was_running=0
+  local process_name
+  if [ -n "$app_name" ] && darwin_app_running "$app_name"; then
+    was_running=1
+  else
+    for process_name in "${process_names[@]}"; do
+      if process_running "$process_name"; then
+        was_running=1
+        break
+      fi
+    done
+  fi
+
+  if [ "$was_running" -eq 0 ]; then
+    return 0
+  fi
+
+  step "Closing ${editor_name}"
+
+  if [ "$(uname -s)" = "Darwin" ] && [ -n "$app_name" ] && command -v osascript >/dev/null 2>&1; then
+    osascript -e "tell application \"${app_name}\" to quit" >/dev/null 2>&1 || true
+  else
+    printf 'Cannot safely close %s automatically on this platform; please quit it and rerun\n' "$editor_name" >&2
+    HAD_ERROR=1
+    return 1
+  fi
+
+  if ! wait_for_shutdown "$app_name" "${process_names[@]}"; then
+    printf 'Failed to close %s safely: %s is still running\n' "$editor_name" "$app_name" >&2
+    HAD_ERROR=1
+    return 1
+  fi
+
+  return 0
+}
+
+backup_cursor_db() {
+  if [ ! -f "$CURSOR_DB" ]; then
+    printf '\n'
+    return
+  fi
+
+  local backup_root
+  if [ -n "$BACKUP_DIR" ]; then
+    backup_root="$BACKUP_DIR"
+  else
+    backup_root="$(dirname "$CURSOR_DB")"
+  fi
+
+  mkdir -p "$backup_root"
+  find "$backup_root" -maxdepth 1 -type f -name 'state.vscdb.backup.*' -delete >/dev/null 2>&1 || true
+  local backup_path="${backup_root}/state.vscdb.backup.$(date +%Y%m%d%H%M%S)"
+  cp "$CURSOR_DB" "$backup_path"
+  printf '%s\n' "$backup_path"
+}
+
+update_cursor_state() {
+  local backup_path="$1"
+
+  step "Updating Cursor state in ${CURSOR_DB}"
+  if ! "$PYTHON_BIN" - "$CURSOR_DB" <<'PY'
+import json
+import sqlite3
+import sys
+import uuid
+from pathlib import Path
+
+db_path = Path(sys.argv[1])
+db_path.parent.mkdir(parents=True, exist_ok=True)
+
+PIN_KEY = "sidebar2.sidebarData.memoized.v1"
+DEFAULT_HIDDEN_KEY = "workbench.view.extension.codexViewContainer.state.hidden"
+APP_KEY = "src.vs.platform.reactivestorage.browser.reactiveStorageServiceImpl.persistentStorage.applicationUser"
+VIEWS_CUSTOMIZATIONS_KEY = "views.customizations"
+AUXILIARYBAR_PINNED_PANELS_KEY = "workbench.auxiliarybar.pinnedPanels"
+AUXILIARYBAR_PLACEHOLDER_PANELS_KEY = "workbench.auxiliarybar.placeholderPanels"
+
+CONTAINER_ID = "workbench.view.extension.codexViewContainer"
+VIEW_ID = "chatgpt.sidebarView"
+EXTENSION_ID = "openai.chatgpt"
+AUXILIARYBAR_PREFIX = "workbench.views.service.auxiliarybar."
+
+
+def read_json(cur, key, default):
+    row = cur.execute("SELECT value FROM ItemTable WHERE key = ?", (key,)).fetchone()
+    if row is None or row[0] in (None, ""):
+        return default
+    return json.loads(row[0])
+
+
+def write_json(cur, key, value):
+    payload = json.dumps(value, separators=(",", ":"))
+    cur.execute(
+        "INSERT OR REPLACE INTO ItemTable(key, value) VALUES(?, ?)",
+        (key, payload),
+    )
+
+
+def delete_key(cur, key):
+    cur.execute("DELETE FROM ItemTable WHERE key = ?", (key,))
+
+
+def write_json_to_cursor_disk_kv(cur, key, value):
+    payload = json.dumps(value, separators=(",", ":"))
+    cur.execute(
+        "INSERT OR REPLACE INTO cursorDiskKV(key, value) VALUES(?, ?)",
+        (key, payload),
+    )
+
+
+def candidate_icon_path():
+    extensions_dir = Path.home() / ".cursor" / "extensions"
+    if not extensions_dir.exists():
+        return None
+
+    matches = sorted(
+        extensions_dir.glob(f"{EXTENSION_ID}-*/resources/blossom-white.svg"),
+        key=lambda path: path.stat().st_mtime,
+        reverse=True,
+    )
+    if not matches:
+        return None
+    return str(matches[0])
+
+
+def is_auxiliarybar_id(value):
+    return bool(value) and value.startswith(AUXILIARYBAR_PREFIX)
+
+
+def generated_auxiliarybar_id():
+    stable_uuid = uuid.uuid5(uuid.NAMESPACE_DNS, EXTENSION_ID)
+    return f"{AUXILIARYBAR_PREFIX}{stable_uuid}"
+
+
+def panel_matches_codex(panel):
+    panel_id = panel.get("id")
+    if not is_auxiliarybar_id(panel_id):
+        return False
+
+    if panel.get("name") == "Codex":
+        return True
+
+    icon_url = panel.get("iconUrl") or {}
+    icon_path = icon_url.get("path", "")
+    if f"/{EXTENSION_ID}-" in icon_path:
+        return True
+
+    for view in panel.get("views", []):
+        if view.get("when") == "chatgpt.doesNotSupportSecondarySidebar":
+            return True
+
+    return False
+
+
+conn = sqlite3.connect(str(db_path))
+cur = conn.cursor()
+cur.execute(
+    "CREATE TABLE IF NOT EXISTS ItemTable (key TEXT UNIQUE ON CONFLICT REPLACE, value BLOB)"
+)
+cur.execute(
+    "CREATE TABLE IF NOT EXISTS cursorDiskKV (key TEXT UNIQUE ON CONFLICT REPLACE, value BLOB)"
+)
+
+sidebar_data = read_json(
+    cur,
+    PIN_KEY,
+    {"pinnedViewContainerIDs": [], "viewContainerOrders": {}},
+)
+pinned_ids = sidebar_data.setdefault("pinnedViewContainerIDs", [])
+sidebar_data["pinnedViewContainerIDs"] = [
+    item for item in pinned_ids if item != CONTAINER_ID
+]
+write_json(cur, PIN_KEY, sidebar_data)
+
+default_hidden_data = read_json(cur, DEFAULT_HIDDEN_KEY, [])
+updated = False
+for item in default_hidden_data:
+    if item.get("id") == VIEW_ID:
+        item["isHidden"] = False
+        updated = True
+        break
+if not updated:
+    default_hidden_data.append({"id": VIEW_ID, "isHidden": False})
+write_json(cur, DEFAULT_HIDDEN_KEY, default_hidden_data)
+
+placeholder_panels = read_json(cur, AUXILIARYBAR_PLACEHOLDER_PANELS_KEY, [])
+pinned_panels = read_json(cur, AUXILIARYBAR_PINNED_PANELS_KEY, [])
+views_customizations = read_json(
+    cur,
+    VIEWS_CUSTOMIZATIONS_KEY,
+    {
+        "viewContainerLocations": {},
+        "viewLocations": {},
+        "viewContainerBadgeEnablementStates": {},
+    },
+)
+view_locations = views_customizations.setdefault("viewLocations", {})
+view_container_locations = views_customizations.setdefault(
+    "viewContainerLocations", {}
+)
+existing_container_id = view_locations.get(VIEW_ID)
+
+codex_container_ids = {
+    panel.get("id")
+    for panel in placeholder_panels
+    if panel_matches_codex(panel)
+}
+if is_auxiliarybar_id(existing_container_id):
+    codex_container_ids.add(existing_container_id)
+
+target_container_id = None
+if is_auxiliarybar_id(existing_container_id):
+    target_container_id = existing_container_id
+else:
+    for panel in placeholder_panels:
+        if panel_matches_codex(panel):
+            target_container_id = panel.get("id")
+            break
+
+if not target_container_id:
+    target_container_id = generated_auxiliarybar_id()
+    codex_container_ids.add(target_container_id)
+
+view_locations[VIEW_ID] = target_container_id
+view_container_locations[target_container_id] = 2
+
+for container_id in list(codex_container_ids):
+    if container_id != target_container_id and container_id not in view_locations.values():
+        view_container_locations.pop(container_id, None)
+
+write_json(cur, VIEWS_CUSTOMIZATIONS_KEY, views_customizations)
+
+icon_path = candidate_icon_path()
+
+target_placeholder_panel = None
+filtered_placeholder_panels = []
+for panel in placeholder_panels:
+    panel_id = panel.get("id")
+    if panel_id == target_container_id:
+        target_placeholder_panel = panel
+        continue
+    if panel_id in codex_container_ids:
+        continue
+    filtered_placeholder_panels.append(panel)
+
+if target_placeholder_panel is None:
+    target_placeholder_panel = {
+        "id": target_container_id,
+        "name": "Codex",
+        "isBuiltin": True,
+        "views": [{"when": "chatgpt.doesNotSupportSecondarySidebar"}],
+    }
+
+target_placeholder_panel["id"] = target_container_id
+target_placeholder_panel["name"] = "Codex"
+target_placeholder_panel["isBuiltin"] = True
+target_placeholder_panel["views"] = [{"when": "chatgpt.doesNotSupportSecondarySidebar"}]
+if icon_path is not None:
+    target_placeholder_panel["iconUrl"] = {
+        "$mid": 1,
+        "path": icon_path,
+        "scheme": "file",
+    }
+
+write_json(
+    cur,
+    AUXILIARYBAR_PLACEHOLDER_PANELS_KEY,
+    [target_placeholder_panel, *filtered_placeholder_panels],
+)
+
+target_pinned_panel = None
+filtered_pinned_panels = []
+for panel in pinned_panels:
+    panel_id = panel.get("id")
+    if panel_id == target_container_id:
+        target_pinned_panel = panel
+        continue
+    if panel_id in codex_container_ids:
+        continue
+    filtered_pinned_panels.append(panel)
+
+if target_pinned_panel is None:
+    target_pinned_panel = {"id": target_container_id}
+
+target_pinned_panel["id"] = target_container_id
+target_pinned_panel["pinned"] = True
+target_pinned_panel["visible"] = False
+
+write_json(
+    cur,
+    AUXILIARYBAR_PINNED_PANELS_KEY,
+    [target_pinned_panel, *filtered_pinned_panels],
+)
+
+write_json(
+    cur,
+    f"{target_container_id}.state.hidden",
+    [{"id": VIEW_ID, "isHidden": False}],
+)
+
+for container_id in codex_container_ids:
+    if container_id != target_container_id:
+        delete_key(cur, f"{container_id}.state.hidden")
+
+app_data = read_json(cur, APP_KEY, {})
+ai_settings = app_data.setdefault("aiSettings", {})
+model_config = ai_settings.setdefault("modelConfig", {})
+composer = model_config.setdefault("composer", {})
+composer["modelName"] = "gpt-5.4-medium"
+composer["maxMode"] = False
+write_json(cur, APP_KEY, app_data)
+
+composer_rows = cur.execute(
+    "SELECT key, value FROM cursorDiskKV WHERE key LIKE 'composerData:%'"
+).fetchall()
+for key, raw_value in composer_rows:
+    if raw_value in (None, ""):
+        continue
+
+    try:
+        composer_data = json.loads(raw_value)
+    except json.JSONDecodeError:
+        continue
+
+    if not (
+        composer_data.get("isAgentic") is True
+        or composer_data.get("unifiedMode") == "agent"
+    ):
+        continue
+
+    row_model_config = composer_data.setdefault("modelConfig", {})
+    row_model_config["modelName"] = "gpt-5.4-medium"
+    row_model_config["maxMode"] = False
+    write_json_to_cursor_disk_kv(cur, key, composer_data)
+
+conn.commit()
+conn.close()
+PY
+  then
+    return 1
+  fi
+
+  if [ -n "$backup_path" ]; then
+    step "Cursor state backup saved to ${backup_path}"
+  fi
+  UPDATED_CURSOR_STATE=1
+}
+
+apply_cursor_state_changes() {
+  if [ -z "$CURSOR_DB" ]; then
+    step "Skipping Cursor state changes: unsupported OS for automatic Cursor DB updates"
+    return 0
+  fi
+
+  mkdir -p "$(dirname "$CURSOR_DB")"
+
+  local backup_path=""
+  backup_path="$(backup_cursor_db)"
+
+  if update_cursor_state "$backup_path"; then
+    return 0
+  fi
+
+  if [ -n "$backup_path" ] && [ -f "$backup_path" ]; then
+    printf 'Failed to update Cursor state; restoring backup from %s\n' "$backup_path" >&2
+    cp "$backup_path" "$CURSOR_DB" >/dev/null 2>&1 || true
+  else
+    printf 'Failed to update Cursor state; removing incomplete database at %s\n' "$CURSOR_DB" >&2
+    rm -f "$CURSOR_DB" >/dev/null 2>&1 || true
+  fi
+
+  HAD_ERROR=1
+  return 1
+}
+
+if [ "$#" -ne 0 ]; then
+  die "This script takes no arguments."
+fi
+
+if [ -z "$CURSOR_DB" ]; then
+  CURSOR_DB="$(default_cursor_db_path || true)"
+fi
+
+resolved_cursor_bin="$(find_editor_bin \
+  "$CURSOR_BIN" \
+  "cursor" \
+  "/Applications/Cursor.app/Contents/Resources/app/bin/cursor" \
+  "/opt/Cursor/resources/app/bin/cursor" \
+  "/opt/cursor/resources/app/bin/cursor" \
+  "/usr/bin/cursor" \
+  || true)"
+resolved_code_bin="$(find_editor_bin \
+  "$CODE_BIN" \
+  "code" \
+  "/Applications/Visual Studio Code.app/Contents/Resources/app/bin/code" \
+  "/usr/bin/code" \
+  "/snap/bin/code" \
+  "/usr/share/code/bin/code" \
+  "/opt/visual-studio-code/bin/code" \
+  || true)"
+resolved_python_bin="$(find_python_bin \
+  "$PYTHON_BIN" \
+  "/usr/bin/python3" \
+  "/opt/homebrew/bin/python3" \
+  "/usr/local/bin/python3" \
+  || true)"
+
+install_cursor=0
+install_vscode=0
+cursor_ready=0
+vscode_ready=0
+
+if [ -n "$resolved_cursor_bin" ]; then
+  install_cursor=1
+else
+  step "Skipping Cursor: editor is not installed"
+fi
+
+if [ -n "$resolved_code_bin" ]; then
+  install_vscode=1
+else
+  step "Skipping VS Code: editor is not installed"
+fi
+
+if [ "$install_cursor" -eq 0 ] && [ "$install_vscode" -eq 0 ]; then
+  step "No supported editors were detected; nothing to do"
+  exit 0
+fi
+
+if [ "$install_cursor" -eq 1 ]; then
+  if [ -n "$CURSOR_DB" ] && [ -z "$resolved_python_bin" ]; then
+    printf 'Skipping Cursor: python3 is required to update Cursor state safely\n' >&2
+    HAD_ERROR=1
+    install_cursor=0
+  elif [ -n "$CURSOR_DB" ] && ! python_can_update_cursor_state "$resolved_python_bin"; then
+    printf 'Skipping Cursor: python3 cannot import the modules required to update Cursor state safely\n' >&2
+    HAD_ERROR=1
+    install_cursor=0
+  else
+    PYTHON_BIN="$resolved_python_bin"
+  fi
+fi
+
+if [ "$install_cursor" -eq 1 ]; then
+  if quit_app_if_running "Cursor" --app-name "Cursor" Cursor cursor; then
+    cursor_ready=1
+  else
+    step "Skipping Cursor: failed to close the running app safely"
+  fi
+fi
+
+if [ "$install_vscode" -eq 1 ]; then
+  if quit_app_if_running "VS Code" --app-name "Visual Studio Code" "Visual Studio Code" Code code; then
+    vscode_ready=1
+  else
+    step "Skipping VS Code: failed to close the running app safely"
+  fi
+fi
+
+cursor_installed=0
+if [ "$install_cursor" -eq 1 ] && [ "$cursor_ready" -eq 1 ]; then
+  if install_extension "Cursor" "$resolved_cursor_bin"; then
+    cursor_installed=1
+  else
+    printf 'Failed to install %s into Cursor\n' "$EXTENSION_ID" >&2
+    HAD_ERROR=1
+  fi
+fi
+
+if [ "$install_vscode" -eq 1 ] && [ "$vscode_ready" -eq 1 ]; then
+  if ! install_extension "VS Code" "$resolved_code_bin"; then
+    printf 'Failed to install %s into VS Code\n' "$EXTENSION_ID" >&2
+    HAD_ERROR=1
+  fi
+fi
+
+if [ "$cursor_installed" -eq 1 ]; then
+  apply_cursor_state_changes || true
+fi
+
+if [ "$UPDATED_CURSOR_STATE" -eq 1 ]; then
+  step "Cursor state changes applied"
+fi
+
+if [ "$HAD_ERROR" -eq 1 ]; then
+  exit 1
+fi
+
+step "Done"