diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09fd593..48315f6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## 0.3.9 — 2026-08-11 — LabWired CLI brand (no OpenCode logo)
+
+- Replace OpenCode home wordmark with LabWired Agent branding via TUI plugin `labwired.brand`.
+- Install and start always ship `plugins/labwired-brand.tsx` + `tui.json` plugin entry.
+- User-facing start messages say LabWired CLI (engine stays OpenCode under the hood).
+
+
 ## 0.3.8 — 2026-08-10 — Product branding + install URLs
 
 - LabWired TUI theme (`branding/themes/labwired.json`) applied on install and agent start.
diff --git a/VERSION b/VERSION
index 6678432..940ac09 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.3.8
+0.3.9
diff --git a/bin/labwired-agent b/bin/labwired-agent
index c583318..4c46e2c 100755
--- a/bin/labwired-agent
+++ b/bin/labwired-agent
@@ -211,6 +211,11 @@ cmd_doctor() {
   else
     printf '\033[33mwarn\033[0m tui: missing — re-run ./install.sh\n'
   fi
+  if [[ -f "$cfg/plugins/labwired-brand.tsx" ]] || [[ -f "$ROOT/plugins/labwired-brand.tsx" ]]; then
+    say "ok  brand-plugin: labwired.brand (replaces OpenCode home logo)"
+  else
+    printf '\033[33mwarn\033[0m brand-plugin: missing — re-run labwired agent or ./install.sh\n'
+  fi
 
   # Five primary packs (ship surface). Aliases optional.
   local skill
@@ -460,7 +465,7 @@ labwired_install_hosted_opencode_config() {
     done
     cp -R "$ROOT/skills/." "$cfg_dir/skills/"
   fi
-  say "OpenCode config: hosted (remote MCP + api.labwired.com/v1) → $cfg_dir/opencode.json"
+  say "LabWired config: hosted (api.labwired.com) → $cfg_dir/opencode.json"
 }
 
 cmd_logout() {
@@ -508,14 +513,14 @@ cmd_whoami() {
   echo "mcp:      remote https://api.labwired.com/mcp (shared labwired_* tools)"
 }
 
-# Product chrome for the OpenCode TUI substrate (theme, banner, terminal title).
-# OpenCode remains the engine; we brand the LabWired product surface.
+# Product chrome: LabWired theme, banner, terminal title, and home_logo plugin
+# that replaces the OpenCode wordmark. Engine remains OpenCode under the hood.
 labwired_apply_branding() {
   local cfg_dir
   cfg_dir="${OPENCODE_CONFIG_DIR:-$HOME/.config/opencode}"
-  mkdir -p "$cfg_dir/themes" "$cfg_dir/branding"
+  mkdir -p "$cfg_dir/themes" "$cfg_dir/branding" "$cfg_dir/plugins"
 
-  # Product theme is always refreshed; user banner/logo stay if already present.
+  # Product theme is always refreshed; user banner assets stay if already present.
   if [[ -f "$ROOT/branding/themes/labwired.json" ]]; then
     cp "$ROOT/branding/themes/labwired.json" "$cfg_dir/themes/labwired.json"
   fi
@@ -529,19 +534,59 @@ labwired_apply_branding() {
       fi
     done
   fi
-  # Default product theme; do not clobber user-chosen themes (tokyonight, etc.).
-  if [[ ! -e "$cfg_dir/tui.json" ]]; then
-    if [[ -f "$ROOT/config/tui.json" ]]; then
-      cp "$ROOT/config/tui.json" "$cfg_dir/tui.json"
-    else
-      printf '%s\n' '{' '  "$schema": "https://opencode.ai/tui.json",' '  "theme": "labwired"' '}' >"$cfg_dir/tui.json"
-    fi
-  elif grep -Eq '"theme"[[:space:]]*:[[:space:]]*"(system|opencode)"' "$cfg_dir/tui.json" 2>/dev/null; then
-    if [[ -f "$ROOT/config/tui.json" ]]; then
-      cp "$ROOT/config/tui.json" "$cfg_dir/tui.json"
-    fi
+
+  # Always ship the brand plugin next to tui.json (path is relative to that file).
+  if [[ -f "$ROOT/plugins/labwired-brand.tsx" ]]; then
+    cp "$ROOT/plugins/labwired-brand.tsx" "$cfg_dir/plugins/labwired-brand.tsx"
   fi
 
+  # Ensure tui.json selects LabWired theme + brand plugin. Preserve other user
+  # keys (keybinds, attention, …) when a tui.json already exists.
+  if [[ -f "$cfg_dir/tui.json" ]]; then
+    python3 - "$cfg_dir/tui.json" <<'PY' 2>/dev/null || true
+import json, sys
+path = sys.argv[1]
+try:
+    cfg = json.load(open(path))
+except Exception:
+    cfg = {}
+if not isinstance(cfg, dict):
+    cfg = {}
+theme = cfg.get("theme")
+if theme in (None, "", "system", "opencode"):
+    cfg["theme"] = "labwired"
+plugins = cfg.get("plugin")
+if not isinstance(plugins, list):
+    plugins = []
+# Normalize plugin specs to strings for membership checks.
+def _spec(p):
+    if isinstance(p, str):
+        return p
+    if isinstance(p, list) and p:
+        return str(p[0])
+    return ""
+wanted = "./plugins/labwired-brand.tsx"
+if not any(_spec(p) == wanted or _spec(p).endswith("labwired-brand.tsx") for p in plugins):
+    plugins = [wanted] + plugins
+cfg["plugin"] = plugins
+cfg.setdefault("$schema", "https://opencode.ai/tui.json")
+open(path, "w").write(json.dumps(cfg, indent=2) + "\n")
+PY
+  elif [[ -f "$ROOT/config/tui.json" ]]; then
+    cp "$ROOT/config/tui.json" "$cfg_dir/tui.json"
+  else
+    cat >"$cfg_dir/tui.json" <<'JSON'
+{
+  "$schema": "https://opencode.ai/tui.json",
+  "theme": "labwired",
+  "plugin": ["./plugins/labwired-brand.tsx"]
+}
+JSON
+  fi
+
+  # Product identity: do not let the engine rename the terminal tab.
+  export OPENCODE_DISABLE_TERMINAL_TITLE=1
+
   # Terminal window / tab title (OSC 0). No-op when not a TTY.
   if [[ -t 1 ]] || [[ -t 2 ]]; then
     printf '\033]0;LabWired Agent\007' 2>/dev/null || true
@@ -597,17 +642,17 @@ labwired_prepare_agent_start() {
     fi
     export LABWIRED_PROFILE=hosted
     export OPENCODE_CONFIG_DIR="$cfg_dir"
-    say "mode: hosted OpenCode + shared tools (api.labwired.com/mcp)"
+    say "mode: LabWired CLI (hosted · api.labwired.com)"
     say "model: ${LABWIRED_MODEL_URL:-}/  id=${LABWIRED_MODEL:-labwired-default}"
   else
     labwired_export_sim || true
     # Local default config if none
     if [[ ! -f "$cfg_dir/opencode.json" && -f "$ROOT/config/opencode.json" ]]; then
       cp "$ROOT/config/opencode.json" "$cfg_dir/opencode.json"
-      say "wrote local OpenCode config → $cfg_dir/opencode.json"
+      say "wrote LabWired config → $cfg_dir/opencode.json"
     fi
     export OPENCODE_CONFIG_DIR="$cfg_dir"
-    say "mode: local OpenCode (npx @labwired/mcp or LABWIRED_CLI sim)"
+    say "mode: LabWired CLI (local tools · npx @labwired/mcp or LABWIRED_CLI)"
   fi
 }
 
@@ -683,7 +728,7 @@ LabWired Agent — write firmware, check on a twin
 
 Usage:
   labwired agent                 Start LabWired Agent (golden-path + MCP)
-  labwired agent opencode …      Same start (OpenCode engine alias)
+  labwired agent opencode …      Same start (engine alias)
   labwired agent login           Device-code sign-in → hosted MCP + model gateway
   labwired agent logout          Clear cloud session
   labwired agent whoami          Show signed-in identity / project
@@ -706,7 +751,7 @@ Usage:
 Ship gate (CI / release):
   ./scripts/ship-gate.sh
 
-OpenCode is the agent runtime. Skills: golden-path · bringup · prove · observe · desk-hw
+LabWired CLI. Skills: golden-path · bringup · prove · observe · desk-hw
 (+ Superpowers process). Knowledge via MCP labwired_part / labwired_datasheet.
 
 Env:
@@ -1016,7 +1061,7 @@ case "${1:-}" in
     fi
     labwired_splash
     echo "labwired: starting LabWired Agent — skill golden-path; packs bringup/prove/observe/desk-hw" >&2
-    echo "labwired: engine OpenCode · twin tools via MCP labwired_* · compose: labwired agent compose …" >&2
+    echo "labwired: LabWired CLI · twin tools via MCP labwired_* · compose: labwired agent compose …" >&2
     exec opencode "$@"
     ;;
   "")
diff --git a/bin/labwired-agent.ps1 b/bin/labwired-agent.ps1
index 9472e77..bde8258 100644
--- a/bin/labwired-agent.ps1
+++ b/bin/labwired-agent.ps1
@@ -80,7 +80,7 @@ Usage:
   labwired agent install-deps    Refresh tools into prefix
   labwired agent help
 
-  Alias: labwired agent opencode ...  (same start; OpenCode engine)
+  Alias: labwired agent opencode ...  (same start; engine alias)
 
 Env:
   LABWIRED_HOME            Install root (default %USERPROFILE%\.labwired)
@@ -93,8 +93,10 @@ function Apply-LabWiredBranding {
   $cfg = if ($env:OPENCODE_CONFIG_DIR) { $env:OPENCODE_CONFIG_DIR } else { Join-Path $env:USERPROFILE ".config\opencode" }
   $themesDir = Join-Path $cfg "themes"
   $brandingDir = Join-Path $cfg "branding"
+  $pluginsDir = Join-Path $cfg "plugins"
   if (-not (Test-Path $themesDir)) { New-Item -ItemType Directory -Path $themesDir -Force | Out-Null }
   if (-not (Test-Path $brandingDir)) { New-Item -ItemType Directory -Path $brandingDir -Force | Out-Null }
+  if (-not (Test-Path $pluginsDir)) { New-Item -ItemType Directory -Path $pluginsDir -Force | Out-Null }
   $themeSrc = Join-Path $AgentHome "branding\themes\labwired.json"
   if (Test-Path $themeSrc) {
     Copy-Item -Force $themeSrc (Join-Path $themesDir "labwired.json")
@@ -104,25 +106,48 @@ function Apply-LabWiredBranding {
   if ((Test-Path $bannerSrc) -and -not (Test-Path $bannerDst)) {
     Copy-Item $bannerSrc $bannerDst
   }
+  $pluginSrc = Join-Path $AgentHome "plugins\labwired-brand.tsx"
+  if (Test-Path $pluginSrc) {
+    Copy-Item -Force $pluginSrc (Join-Path $pluginsDir "labwired-brand.tsx")
+  }
   $tuiSrc = Join-Path $AgentHome "config\tui.json"
   $tuiDst = Join-Path $cfg "tui.json"
-  $writeTui = -not (Test-Path $tuiDst)
-  if (-not $writeTui -and (Test-Path $tuiDst)) {
-    $existing = Get-Content -Raw $tuiDst
-    if ($existing -match '"theme"\s*:\s*"(system|opencode)"') { $writeTui = $true }
-  }
-  if ($writeTui) {
+  $wantedPlugin = "./plugins/labwired-brand.tsx"
+  if (-not (Test-Path $tuiDst)) {
     if (Test-Path $tuiSrc) {
       Copy-Item -Force $tuiSrc $tuiDst
     } else {
-      Set-Content -Path $tuiDst -Value @"
-{
-  "`$schema": "https://opencode.ai/tui.json",
-  "theme": "labwired"
-}
-"@ -Encoding utf8
+      Set-Content -Path $tuiDst -Value (@{
+        '$schema' = 'https://opencode.ai/tui.json'
+        theme = 'labwired'
+        plugin = @($wantedPlugin)
+      } | ConvertTo-Json) -Encoding utf8
+    }
+  } else {
+    try {
+      $cfgObj = Get-Content -Raw $tuiDst | ConvertFrom-Json
+      if (-not $cfgObj.theme -or $cfgObj.theme -in @('system', 'opencode')) {
+        $cfgObj | Add-Member -NotePropertyName theme -NotePropertyValue 'labwired' -Force
+      }
+      $plugins = @()
+      if ($cfgObj.plugin) { $plugins = @($cfgObj.plugin) }
+      $hasBrand = $false
+      foreach ($p in $plugins) {
+        $s = if ($p -is [string]) { $p } elseif ($p -is [array] -and $p.Count -gt 0) { [string]$p[0] } else { '' }
+        if ($s -eq $wantedPlugin -or $s.EndsWith('labwired-brand.tsx')) { $hasBrand = $true; break }
+      }
+      if (-not $hasBrand) {
+        $cfgObj | Add-Member -NotePropertyName plugin -NotePropertyValue (@($wantedPlugin) + $plugins) -Force
+      }
+      if (-not $cfgObj.'$schema') {
+        $cfgObj | Add-Member -NotePropertyName '$schema' -NotePropertyValue 'https://opencode.ai/tui.json' -Force
+      }
+      ($cfgObj | ConvertTo-Json -Depth 8) | Set-Content -Path $tuiDst -Encoding utf8
+    } catch {
+      if (Test-Path $tuiSrc) { Copy-Item -Force $tuiSrc $tuiDst }
     }
   }
+  $env:OPENCODE_DISABLE_TERMINAL_TITLE = "1"
   try {
     $Host.UI.RawUI.WindowTitle = "LabWired Agent"
   } catch { }
@@ -294,7 +319,7 @@ switch ($cmd) {
       Write-Host "labwired: note - no local sim; hosted MCP verify still works." -ForegroundColor Yellow
     }
     Show-LabWiredSplash
-    Write-Host "labwired: starting LabWired Agent (OpenCode engine)" -ForegroundColor Cyan
+    Write-Host "labwired: starting LabWired CLI" -ForegroundColor Cyan
     & opencode @argsRest
   }
   "" {
@@ -307,7 +332,7 @@ switch ($cmd) {
       Write-Host "labwired: note - no local sim; hosted MCP verify still works." -ForegroundColor Yellow
     }
     Show-LabWiredSplash
-    Write-Host "labwired: starting LabWired Agent (OpenCode engine)" -ForegroundColor Cyan
+    Write-Host "labwired: starting LabWired CLI" -ForegroundColor Cyan
     & opencode @argsRest
   }
   default {
diff --git a/config/tui.json b/config/tui.json
index 70e0b71..e4dcf05 100644
--- a/config/tui.json
+++ b/config/tui.json
@@ -1,4 +1,5 @@
 {
   "$schema": "https://opencode.ai/tui.json",
-  "theme": "labwired"
+  "theme": "labwired",
+  "plugin": ["./plugins/labwired-brand.tsx"]
 }
diff --git a/install.sh b/install.sh
index cdd8ae0..647462d 100755
--- a/install.sh
+++ b/install.sh
@@ -320,7 +320,7 @@ rsync -a --delete \
   --exclude '.DS_Store' \
   --exclude '.grok' \
   "$SRC/" "$AGENT_HOME/" 2>/dev/null || {
-  for d in bin lib config skills branding fixtures mcp scripts docs tests share examples; do
+  for d in bin lib config skills branding plugins fixtures mcp scripts docs tests share examples; do
     if [[ -d "$SRC/$d" ]]; then
       mkdir -p "$AGENT_HOME/$d"
       cp -R "$SRC/$d/." "$AGENT_HOME/$d/"
@@ -354,10 +354,10 @@ WRAP
 chmod 0755 "$_prefix_dispatcher_tmp"
 mv -f "$_prefix_dispatcher_tmp" "${PREFIX_BIN}/labwired"
 
-# Branding into OpenCode config (product identity).
-# Force-refresh LabWired theme + default tui theme. Flat branding files are
-# owned only when absent so user banners/custom assets survive reinstall.
-mkdir -p "$CFG_DIR/branding" "$CFG_DIR/themes"
+# Branding into config (product identity).
+# Force-refresh LabWired theme, brand plugin (replaces OpenCode home logo), and
+# default tui theme. Flat branding files are owned only when absent.
+mkdir -p "$CFG_DIR/branding" "$CFG_DIR/themes" "$CFG_DIR/plugins"
 if [[ -f "$AGENT_HOME/branding/themes/labwired.json" ]]; then
   cp "$AGENT_HOME/branding/themes/labwired.json" "$CFG_DIR/themes/labwired.json"
   grep -Fqx "themes/labwired.json" "$MANIFEST" 2>/dev/null || printf '%s\n' "themes/labwired.json" >>"$MANIFEST"
@@ -370,15 +370,47 @@ while IFS= read -r branding_file; do
   esac
   _install_owned_file_if_absent "$branding_file" "$CFG_DIR/branding/$rel"
 done < <(find "$AGENT_HOME/branding" -type f -print 2>/dev/null)
+if [[ -f "$AGENT_HOME/plugins/labwired-brand.tsx" ]]; then
+  cp "$AGENT_HOME/plugins/labwired-brand.tsx" "$CFG_DIR/plugins/labwired-brand.tsx"
+  grep -Fqx "plugins/labwired-brand.tsx" "$MANIFEST" 2>/dev/null || printf '%s\n' "plugins/labwired-brand.tsx" >>"$MANIFEST"
+fi
 if [[ -f "$AGENT_HOME/config/tui.json" ]]; then
+  # Always refresh product tui defaults (theme + brand plugin). User keybinds
+  # survive if already present via merge below.
   if [[ ! -e "$CFG_DIR/tui.json" && ! -L "$CFG_DIR/tui.json" ]]; then
     cp "$AGENT_HOME/config/tui.json" "$CFG_DIR/tui.json"
-    grep -Fqx "tui.json" "$MANIFEST" 2>/dev/null || printf '%s\n' "tui.json" >>"$MANIFEST"
-  elif grep -Eq '"theme"[[:space:]]*:[[:space:]]*"(system|opencode)"' "$CFG_DIR/tui.json" 2>/dev/null; then
-    # Upgrade stock OpenCode defaults to LabWired product theme.
-    cp "$AGENT_HOME/config/tui.json" "$CFG_DIR/tui.json"
-    grep -Fqx "tui.json" "$MANIFEST" 2>/dev/null || printf '%s\n' "tui.json" >>"$MANIFEST"
+  else
+    python3 - "$CFG_DIR/tui.json" "$AGENT_HOME/config/tui.json" <<'PY' 2>/dev/null || cp "$AGENT_HOME/config/tui.json" "$CFG_DIR/tui.json"
+import json, sys
+dst, src = sys.argv[1], sys.argv[2]
+try:
+    cfg = json.load(open(dst))
+except Exception:
+    cfg = {}
+try:
+    product = json.load(open(src))
+except Exception:
+    product = {"theme": "labwired", "plugin": ["./plugins/labwired-brand.tsx"]}
+if not isinstance(cfg, dict):
+    cfg = {}
+if cfg.get("theme") in (None, "", "system", "opencode"):
+    cfg["theme"] = product.get("theme", "labwired")
+plugins = cfg.get("plugin")
+if not isinstance(plugins, list):
+    plugins = []
+wanted = "./plugins/labwired-brand.tsx"
+def _spec(p):
+    if isinstance(p, str): return p
+    if isinstance(p, list) and p: return str(p[0])
+    return ""
+if not any(_spec(p) == wanted or _spec(p).endswith("labwired-brand.tsx") for p in plugins):
+    plugins = [wanted] + list(plugins)
+cfg["plugin"] = plugins
+cfg.setdefault("$schema", product.get("$schema", "https://opencode.ai/tui.json"))
+open(dst, "w").write(json.dumps(cfg, indent=2) + "\n")
+PY
   fi
+  grep -Fqx "tui.json" "$MANIFEST" 2>/dev/null || printf '%s\n' "tui.json" >>"$MANIFEST"
 fi
 
 # Thin user PATH shim — self-contained (no need to source env.sh first)
diff --git a/package.json b/package.json
index d23180e..943d140 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@labwired/agent",
-  "version": "0.3.8",
+  "version": "0.3.9",
   "description": "Firmware agent with LabWired twin verification",
   "license": "MIT",
   "homepage": "https://labwired.com",
@@ -61,6 +61,7 @@
     "branding/logo.svg",
     "branding/theme.css",
     "branding/themes/labwired.json",
+    "plugins/labwired-brand.tsx",
     "share/smoke/status-parser-model-verified.json",
     "share/smoke/status-parser-failed.json",
     "scripts/profiles/esp32c3-serial.sh",
diff --git a/plugins/labwired-brand.tsx b/plugins/labwired-brand.tsx
new file mode 100644
index 0000000..764b2b1
--- /dev/null
+++ b/plugins/labwired-brand.tsx
@@ -0,0 +1,58 @@
+/**
+ * LabWired TUI brand plugin.
+ *
+ * Replaces the OpenCode home_logo slot so the product surface is LabWired CLI,
+ * not OpenCode. Engine remains OpenCode under the hood.
+ *
+ * Loaded via config/tui.json → plugin: ["./plugins/labwired-brand.tsx"]
+ * (path is relative to the tui.json that declares it; install copies this
+ * file next to ~/.config/opencode/tui.json as plugins/labwired-brand.tsx).
+ */
+/** @jsxImportSource @opentui/solid */
+import type { TuiPlugin, TuiPluginModule } from "@opencode-ai/plugin/tui"
+
+type ColorMap = Record<string, unknown>
+
+function color(map: ColorMap, name: string, fallback: string): unknown {
+  const value = map[name]
+  if (typeof value === "string" && value.trim()) return value
+  if (value != null && typeof value === "object") return value
+  return fallback
+}
+
+const tui: TuiPlugin = async (api) => {
+  api.slots.register({
+    // Win replace mode against the built-in OpenCode Logo.
+    order: 0,
+    slots: {
+      home_logo(ctx) {
+        const map = (ctx.theme?.current ?? {}) as ColorMap
+        const primary = color(map, "primary", "#3d8fd1")
+        const muted = color(map, "textMuted", "#8b91a3")
+        const text = color(map, "text", "#e8eaf0")
+        // Simple, product-owned mark — not the OpenCode wordmark.
+        const art = [
+          "  L A B W I R E D",
+          "  ───────────────",
+          "  A G E N T",
+        ]
+        return (
+          <box flexDirection="column" alignItems="center">
+            {art.map((line, i) => (
+              <text fg={i === 1 ? muted : primary}>{line}</text>
+            ))}
+            <box height={1} />
+            <text fg={text}>Write firmware · check on a twin</text>
+          </box>
+        )
+      },
+    },
+  })
+}
+
+const plugin: TuiPluginModule & { id: string } = {
+  id: "labwired.brand",
+  tui,
+}
+
+export default plugin
diff --git a/scripts/install.ps1 b/scripts/install.ps1
index e65496d..1ca3742 100644
--- a/scripts/install.ps1
+++ b/scripts/install.ps1
@@ -623,7 +623,7 @@ function Install-OpenCodeConfig {
       if (-not (Test-Path $destination)) { Protect-Mutation $destination; Copy-Safe $_.FullName $destination -Recurse }
     }
   }
-  # LabWired product chrome: always refresh theme; keep user banner if present.
+  # LabWired product chrome: theme + brand plugin (replaces OpenCode home logo).
   $themeSrc = Join-Path $agent "branding\themes\labwired.json"
   if (Test-Path $themeSrc) {
     $themesDir = Join-Path $cfg "themes"
@@ -645,20 +645,47 @@ function Install-OpenCodeConfig {
       }
     }
   }
+  $pluginSrc = Join-Path $agent "plugins\labwired-brand.tsx"
+  if (Test-Path $pluginSrc) {
+    $pluginsDir = Join-Path $cfg "plugins"
+    Protect-Mutation $pluginsDir
+    Ensure-Dir $pluginsDir
+    $pluginDst = Join-Path $pluginsDir "labwired-brand.tsx"
+    Protect-Mutation $pluginDst
+    Copy-Safe $pluginSrc $pluginDst
+  }
   $tuiSrc = Join-Path $agent "config\tui.json"
   $tuiDst = Join-Path $cfg "tui.json"
   if (Test-Path $tuiSrc) {
-    $shouldWriteTui = -not (Test-Path $tuiDst)
-    if (-not $shouldWriteTui) {
-      $existing = Get-Content -Raw $tuiDst
-      if ($existing -match '"theme"\s*:\s*"(system|opencode)"') { $shouldWriteTui = $true }
-    }
-    if ($shouldWriteTui) {
-      Protect-Mutation $tuiDst
+    Protect-Mutation $tuiDst
+    if (-not (Test-Path $tuiDst)) {
       Copy-Safe $tuiSrc $tuiDst
+    } else {
+      # Merge product theme + brand plugin into existing tui.json.
+      try {
+        $cfgObj = Get-Content -Raw $tuiDst | ConvertFrom-Json
+        $product = Get-Content -Raw $tuiSrc | ConvertFrom-Json
+        if (-not $cfgObj.theme -or $cfgObj.theme -in @('system', 'opencode')) {
+          $cfgObj | Add-Member -NotePropertyName theme -NotePropertyValue $product.theme -Force
+        }
+        $wanted = "./plugins/labwired-brand.tsx"
+        $plugins = @()
+        if ($cfgObj.plugin) { $plugins = @($cfgObj.plugin) }
+        $has = $false
+        foreach ($p in $plugins) {
+          $s = if ($p -is [string]) { $p } else { '' }
+          if ($s -eq $wanted -or $s.EndsWith('labwired-brand.tsx')) { $has = $true; break }
+        }
+        if (-not $has) {
+          $cfgObj | Add-Member -NotePropertyName plugin -NotePropertyValue (@($wanted) + $plugins) -Force
+        }
+        ($cfgObj | ConvertTo-Json -Depth 8) | Set-Content -Path $tuiDst -Encoding utf8
+      } catch {
+        Copy-Safe $tuiSrc $tuiDst
+      }
     }
   }
-  Ok "LabWired config -> $cfg (OpenCode engine)"
+  Ok "LabWired config -> $cfg"
 }
 
 # -- main ----------------------------------------