Release skill 4.3.1

Publish the launcher setup diagnostics hotfix and refresh generated provider version metadata.

AI-assisted by Codex.

.agent/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 allowed-tools:
   - Bash(npx impeccable *)

.agent/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.agent/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.agents/skills/impeccable/SKILL.md

@@ -2,7 +2,7 @@
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
 metadata:
-  version: 4.3.0
+  version: 4.3.1
 ---
 
 This skill gives you the tools and permission to create design that earns to be called out-of-distribution craft: Whereas before, your design work would have been safe, timid and measured, you now approach every design task as an award-winning design director with impeccable understanding for what makes exceptional design work: production-grade code, peak creativity, a clear POV, deep understanding of the needs of the client and users, and exceptional craft.

.agents/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.agents/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.claude-plugin/marketplace.json

@@ -12,7 +12,7 @@
     {
       "name": "impeccable",
       "description": "Design fluency for frontend development. 1 skill with 23 commands (/impeccable polish, /impeccable audit, /impeccable critique, etc.) and curated anti-pattern detection.",
-      "version": "4.3.0",
+      "version": "4.3.1",
       "author": {
         "name": "Paul Bakaus",
         "email": "paul@paulbakaus.com"

.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "impeccable",
   "description": "Design fluency for frontend development. 1 skill with 23 commands (/impeccable polish, /impeccable audit, /impeccable critique, etc.) and curated anti-pattern detection.",
-  "version": "4.3.0",
+  "version": "4.3.1",
   "author": {
     "name": "Paul Bakaus",
     "email": "paul@paulbakaus.com"

.claude/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.claude/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.claude/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.cursor/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 ---
 

.cursor/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.cursor/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.dsh/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 license: Apache 2.0
 ---

.dsh/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.dsh/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.gemini/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 ---
 
 This skill gives you the tools and permission to create design that earns to be called out-of-distribution craft: Whereas before, your design work would have been safe, timid and measured, you now approach every design task as an award-winning design director with impeccable understanding for what makes exceptional design work: production-grade code, peak creativity, a clear POV, deep understanding of the needs of the client and users, and exceptional craft.

.gemini/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.gemini/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.github/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.github/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.github/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.grok/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.grok/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.grok/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.hermes/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 ---
 

.hermes/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.hermes/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.kiro/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 ---
 

.kiro/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.kiro/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.opencode/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.opencode/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.opencode/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.pi/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 allowed-tools:
   - Bash(npx impeccable *)

.pi/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.pi/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.qoder/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.qoder/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.qoder/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.rovodev/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.rovodev/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.rovodev/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.trae-cn/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.trae-cn/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.trae-cn/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.trae/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

.trae/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.trae/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.veto/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 ---
 

.veto/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.veto/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

.vibe/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 license: Apache 2.0
 allowed-tools:

.vibe/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

.vibe/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

crates/context/src/hook_markers.rs

@@ -30,9 +30,39 @@ static LAUNCHER_HOOK_MARKER: Lazy<Regex> = Lazy::new(|| {
     Regex::new(r#"skills/impeccable/scripts/impeccable(?:\.cmd|\.exe)?["']?\s+hook(?:-before-edit|-probe|-after-edit|-stop)?(?:\s|$|["'&|;)])"#).unwrap()
 });
 
+/// User-scope Windows commands embed a JSON-quoted path whose backslashes are
+/// doubled in the command string (#784). #604's single `\`→`/` replace is not
+/// enough: `\\` becomes `//`, which breaks `skills/impeccable` matching.
+/// A leading `//` after a quote (or at the start of the string) is a UNC
+/// prefix and stays two slashes, so doctor still probes `//server/share/...`.
+fn normalize_hook_separators(command: &str) -> String {
+    let mut out = String::with_capacity(command.len());
+    let mut chars = command.chars().peekable();
+    let mut prev: Option<char> = None;
+    while let Some(ch) = chars.next() {
+        if ch != '\\' && ch != '/' {
+            out.push(ch);
+            prev = Some(ch);
+            continue;
+        }
+        let mut n = 1usize;
+        while matches!(chars.peek(), Some('\\' | '/')) {
+            chars.next();
+            n += 1;
+        }
+        out.push('/');
+        if n >= 2 && matches!(prev, None | Some('"' | '\'')) {
+            out.push('/');
+        }
+        prev = Some('/');
+    }
+    out
+}
+
 /// True when `command` invokes an Impeccable hook in either generation's spelling.
 pub fn is_impeccable_hook_command(command: &str) -> bool {
-    LEGACY_HOOK_SCRIPT_MARKERS.iter().any(|m| command.contains(m)) || LAUNCHER_HOOK_MARKER.is_match(command)
+    let command = normalize_hook_separators(command);
+    LEGACY_HOOK_SCRIPT_MARKERS.iter().any(|m| command.contains(m)) || LAUNCHER_HOOK_MARKER.is_match(&command)
 }
 
 /// True when `command` invokes an Impeccable hook in the launcher generation
@@ -40,7 +70,7 @@ pub fn is_impeccable_hook_command(command: &str) -> bool {
 /// one: install/update use this to decide which manifests still need
 /// migrating to the launcher form.
 pub fn is_launcher_hook_command(command: &str) -> bool {
-    LAUNCHER_HOOK_MARKER.is_match(command)
+    LAUNCHER_HOOK_MARKER.is_match(&normalize_hook_separators(command))
 }
 
 /// The launcher-era markers `context` and `doctor` treat as the design hook
@@ -54,9 +84,10 @@ static LAUNCHER_DESIGN_HOOK: Lazy<Regex> = Lazy::new(|| {
 /// `hook-before-edit`) in either spelling; the JS `context.mjs` scan and
 /// `staleness-deep` HOOK_SCRIPT_MARKERS both meant exactly these two.
 pub fn is_design_hook_command(command: &str) -> bool {
+    let command = normalize_hook_separators(command);
     command.contains("skills/impeccable/scripts/hook.mjs")
         || command.contains("skills/impeccable/scripts/hook-before-edit.mjs")
-        || LAUNCHER_DESIGN_HOOK.is_match(command)
+        || LAUNCHER_DESIGN_HOOK.is_match(&command)
 }
 
 /// True when `command` runs the design hook (`hook` / `hook-before-edit`) in
@@ -66,7 +97,7 @@ pub fn is_design_hook_command(command: &str) -> bool {
 /// so the hook is dead and `MANUAL_DETECTOR_REQUIRED` must fire until an
 /// install/update repairs it.
 pub fn is_launcher_design_hook_command(command: &str) -> bool {
-    LAUNCHER_DESIGN_HOOK.is_match(command)
+    LAUNCHER_DESIGN_HOOK.is_match(&normalize_hook_separators(command))
 }
 
 /// The shell token that names the hook program inside `command`, for
@@ -74,7 +105,11 @@ pub fn is_launcher_design_hook_command(command: &str) -> bool {
 /// path in the binary form. `None` when the command carries no marker or
 /// the token cannot be isolated (a `'\''` escape sequence, for instance).
 pub fn hook_program_token(command: &str) -> Option<String> {
-    if !is_design_hook_command(command) {
+    if command.contains("'\\''") {
+        return None;
+    }
+    let command = normalize_hook_separators(command);
+    if !is_design_hook_command(&command) {
         return None;
     }
     static QUOTED: Lazy<Regex> = Lazy::new(|| {
@@ -86,16 +121,13 @@ pub fn hook_program_token(command: &str) -> Option<String> {
     static BARE: Lazy<Regex> = Lazy::new(|| {
         Regex::new(r#"([^\s"'|&;()]*skills/impeccable/scripts/(?:hook(?:-before-edit)?\.mjs|impeccable(?:\.cmd|\.exe)?))"#).unwrap()
     });
-    if let Some(m) = QUOTED.captures(command) {
+    if let Some(m) = QUOTED.captures(&command) {
         return Some(m[1].to_string());
     }
-    if command.contains("'\\''") {
-        return None;
-    }
-    if let Some(m) = SINGLE.captures(command) {
+    if let Some(m) = SINGLE.captures(&command) {
         return Some(m[1].to_string());
     }
-    BARE.captures(command).map(|m| m[1].to_string())
+    BARE.captures(&command).map(|m| m[1].to_string())
 }
 
 #[cfg(test)]
@@ -183,4 +215,45 @@ mod tests {
         assert_eq!(hook_program_token("'/x/it'\\''s/.claude/skills/impeccable/scripts/impeccable' hook"), None);
         assert_eq!(hook_program_token("echo hi"), None);
     }
+
+    #[test]
+    fn recognizes_json_escaped_windows_launcher_path() {
+        let launcher = r"C:\Users\alice\.claude\skills\impeccable\scripts\impeccable";
+        let quoted = serde_json::to_string(launcher).unwrap();
+        let cmd = format!("[ ! -f {quoted} ] || {quoted} hook");
+        assert!(is_impeccable_hook_command(&cmd), "{cmd}");
+        assert!(is_launcher_hook_command(&cmd), "{cmd}");
+        assert!(is_design_hook_command(&cmd), "{cmd}");
+        assert_eq!(
+            hook_program_token(&cmd).as_deref(),
+            Some("C:/Users/alice/.claude/skills/impeccable/scripts/impeccable")
+        );
+    }
+
+    #[test]
+    fn recognizes_single_backslash_windows_path() {
+        let cmd = r#"[ ! -f "C:\Users\alice\.claude\skills\impeccable\scripts\impeccable" ] || "C:\Users\alice\.claude\skills\impeccable\scripts\impeccable" hook"#;
+        assert!(is_impeccable_hook_command(cmd), "{cmd}");
+        assert!(is_launcher_hook_command(cmd), "{cmd}");
+        assert!(is_design_hook_command(cmd), "{cmd}");
+    }
+
+    #[test]
+    fn preserves_unc_prefix_in_program_token() {
+        let launcher = r"\\server\share\.claude\skills\impeccable\scripts\impeccable";
+        let quoted = serde_json::to_string(launcher).unwrap();
+        let json_escaped = format!("[ ! -f {quoted} ] || {quoted} hook");
+        assert!(is_impeccable_hook_command(&json_escaped), "{json_escaped}");
+        assert_eq!(
+            hook_program_token(&json_escaped).as_deref(),
+            Some("//server/share/.claude/skills/impeccable/scripts/impeccable")
+        );
+
+        let single = r#"[ ! -f "\\server\share\.claude\skills\impeccable\scripts\impeccable" ] || "\\server\share\.claude\skills\impeccable\scripts\impeccable" hook"#;
+        assert!(is_impeccable_hook_command(single), "{single}");
+        assert_eq!(
+            hook_program_token(single).as_deref(),
+            Some("//server/share/.claude/skills/impeccable/scripts/impeccable")
+        );
+    }
 }

crates/skills/src/hook_manifest.rs

@@ -219,13 +219,10 @@ fn rewrite_value(value: &Value, provider: &str, quoted: &QuotedPath, win32: bool
     }
 }
 
-/// JS: valueHasImpeccableHookMarker(value). Command separators are
-/// normalized to `/` first so a legacy Windows-path guard is still
-/// recognized as ours and replaced instead of duplicated (upstream
-/// 665c51b9, #604).
+/// JS: valueHasImpeccableHookMarker(value).
 pub fn value_has_impeccable_hook_marker(value: &Value) -> bool {
     match value {
-        Value::String(s) => is_impeccable_hook_command(&s.replace('\\', "/")),
+        Value::String(s) => is_impeccable_hook_command(s),
         Value::Array(a) => a.iter().any(value_has_impeccable_hook_marker),
         Value::Object(o) => o.values().any(value_has_impeccable_hook_marker),
         _ => false,
@@ -233,12 +230,9 @@ pub fn value_has_impeccable_hook_marker(value: &Value) -> bool {
 }
 
 /// True when `value` names an Impeccable hook in the launcher generation.
-/// Separators are normalized to `/` first, matching
-/// `value_has_impeccable_hook_marker`, so a legacy Windows-path launcher
-/// command is still recognized.
 pub fn value_has_launcher_hook_marker(value: &Value) -> bool {
     match value {
-        Value::String(s) => is_launcher_hook_command(&s.replace('\\', "/")),
+        Value::String(s) => is_launcher_hook_command(s),
         Value::Array(a) => a.iter().any(value_has_launcher_hook_marker),
         Value::Object(o) => o.values().any(value_has_launcher_hook_marker),
         _ => false,

crates/skills/tests/hook_manifest_tests.rs

@@ -357,3 +357,57 @@ fn hook_artifacts_map_providers_to_manifest_files() {
     assert_eq!(c[0].dest, jsp::join(&["/p", ".codex", "hooks.json"]));
     assert!(c[0].shared_dest.is_none());
 }
+
+fn windows_user_scope_hook_command() -> String {
+    let launcher = r"C:\Users\alice\.claude\skills\impeccable\scripts\impeccable";
+    let q = json_string(launcher);
+    format!("[ ! -f {q} ] || {q} hook")
+}
+
+#[test]
+fn merge_json_escaped_windows_launcher_is_idempotent() {
+    let cmd = windows_user_scope_hook_command();
+    let hook_entry = |cmd: String| {
+        json!({ "matcher": "Edit", "hooks": [{ "type": "command", "command": cmd }] })
+    };
+    let stop_entry = |cmd: String| {
+        json!({ "hooks": [{ "type": "command", "command": cmd, "timeout": 30 }] })
+    };
+    let existing = json!({
+        "hooks": {
+            "PostToolUse": [hook_entry(cmd.clone())],
+            "Stop": [stop_entry(cmd.clone())]
+        }
+    });
+    let fresh = json!({
+        "description": "fresh",
+        "hooks": {
+            "PostToolUse": [hook_entry(cmd.clone())],
+            "Stop": [stop_entry(cmd.clone())]
+        }
+    });
+    let merged = merge_hook_manifests(&existing, &fresh);
+    assert_eq!(merged["hooks"]["PostToolUse"].as_array().unwrap().len(), 1);
+    assert_eq!(merged["hooks"]["Stop"].as_array().unwrap().len(), 1);
+    let merged2 = merge_hook_manifests(&merged, &fresh);
+    assert_eq!(merged2["hooks"]["PostToolUse"].as_array().unwrap().len(), 1);
+    assert_eq!(merged2["hooks"]["Stop"].as_array().unwrap().len(), 1);
+}
+
+#[test]
+fn merge_heals_triplicated_stop_groups() {
+    let cmd = windows_user_scope_hook_command();
+    let stop_entry = json!({ "hooks": [{ "type": "command", "command": cmd.clone(), "timeout": 30 }] });
+    let existing = json!({
+        "hooks": {
+            "Stop": [stop_entry.clone(), stop_entry.clone(), stop_entry]
+        }
+    });
+    let fresh = json!({
+        "hooks": {
+            "Stop": [json!({ "hooks": [{ "type": "command", "command": cmd, "timeout": 30 }] })]
+        }
+    });
+    let merged = merge_hook_manifests(&existing, &fresh);
+    assert_eq!(merged["hooks"]["Stop"].as_array().unwrap().len(), 1);
+}

cursor-plugin/.cursor-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "impeccable",
-  "version": "4.3.0",
+  "version": "4.3.1",
   "description": "Design and refine interfaces with Impeccable skills, specialist agents, and design checks.",
   "author": {
     "name": "Renaissance Geek, Inc."

cursor-plugin/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 license: Apache 2.0
 ---
 

cursor-plugin/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

cursor-plugin/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

plugin/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "impeccable",
   "description": "Design fluency for frontend development. 1 skill with 23 commands (/impeccable polish, /impeccable audit, /impeccable critique, etc.) and curated anti-pattern detection.",
-  "version": "4.3.0",
+  "version": "4.3.1",
   "author": {
     "name": "Paul Bakaus",
     "email": "paul@paulbakaus.com"

plugin/.grok-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "impeccable",
-  "version": "4.3.0",
+  "version": "4.3.1",
   "description": "Design fluency for frontend development. 1 skill with 23 commands (/impeccable polish, /impeccable audit, /impeccable critique, etc.) and curated anti-pattern detection.",
   "author": {
     "name": "Paul Bakaus",

plugin/skills/impeccable/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: impeccable
 description: Use when the user wants to design, redesign, shape, critique, audit, polish, clarify, distill, harden, optimize, adapt, animate, colorize, extract, or otherwise improve a frontend interface. Covers websites, landing pages, dashboards, product UI, app shells, components, forms, settings, onboarding, and empty states. Handles UX review, visual hierarchy, information architecture, cognitive load, accessibility, performance, responsive behavior, theming, anti-patterns, typography, fonts, spacing, layout, alignment, color, motion, micro-interactions, UX copy, error states, edge cases, i18n, and reusable design systems or tokens. Also use for bland designs that need to become bolder or more delightful, loud designs that should become quieter, live browser iteration on UI elements, or ambitious visual effects that should feel technically extraordinary. Not for backend-only or non-UI tasks.
-version: 4.3.0
+version: 4.3.1
 user-invocable: true
 argument-hint: "[shape · audit|critique · animate|bolder|colorize|delight|layout|overdrive|quieter|typeset · adapt|clarify|distill · harden|onboard|optimize|polish · init|document|extract|live] [target]"
 license: Apache 2.0

plugin/skills/impeccable/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

plugin/skills/impeccable/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

skill/scripts/impeccable

@@ -87,6 +87,11 @@ fi
 # Last resort: fetch this version's binary for the current platform from the
 # public release channel into the user cache. Needs network; sandboxes without
 # egress preinstall the binary on PATH instead.
+setup_help() {
+  echo "Engine $version setup needs network access and write permission to $cache_root/bin/$version." >&2
+  echo "Run this launcher ($0) with engine-probe in a terminal that has those permissions, then retry the original command." >&2
+  echo "Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary." >&2
+}
 fetch_url() {
   if command -v curl >/dev/null 2>&1; then
     curl -fsSL --retry 2 -o "$tmp" "$1" 2>/dev/null
@@ -119,7 +124,18 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
   [ "$os" = windows ] && asset="$asset.exe"
   url="$base/engine-v$version/$asset"
   tmp="$cache_root/bin/$version/.impeccable.part.$$"
-  mkdir -p "$cache_root/bin/$version" 2>/dev/null
+  if ! mkdir -p "$cache_root/bin/$version" 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot create cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
+  # Check the actual staging file, not just directory existence: a cache from
+  # an earlier run can be readable but no longer writable inside a sandbox.
+  if ! (umask 077; : > "$tmp") 2>/dev/null; then
+    echo "impeccable: engine $version is not installed; cannot write to cache directory: $cache_root/bin/$version" >&2
+    setup_help
+    exit 127
+  fi
   fetched=0
   if fetch_url "$url"; then
     fetched=1
@@ -180,6 +196,9 @@ if [ -n "$version" ] && [ "$os" != unknown ] && [ "$arch" != unknown ]; then
     exec "$cached" "$@"
   fi
   rm -f "$tmp" 2>/dev/null
+  echo "impeccable: could not download engine $version from $url; check network access, the release URL, and curl or wget availability." >&2
+  setup_help
+  exit 127
 fi
 
 echo "impeccable: no engine binary for $os-$arch found (looked in $bin, $cached, PATH)." >&2

skill/scripts/impeccable.cmd

@@ -68,18 +68,27 @@ rem another launcher's probe: fail fast and quiet instead.
 if defined IMPECCABLE_LAUNCHER_PROBE exit /b 127
 if not defined version goto fail
 where curl.exe >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto curl_missing
 if not defined IMPECCABLE_DOWNLOAD_BASE set "IMPECCABLE_DOWNLOAD_BASE=https://github.com/pbakaus/impeccable/releases/download"
-if not exist "%IMPECCABLE_HOME%\bin\%version%" mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if exist "%IMPECCABLE_HOME%\bin\%version%\" goto cache_ready
+mkdir "%IMPECCABLE_HOME%\bin\%version%" >nul 2>nul
+if errorlevel 1 goto cache_directory_failed
+:cache_ready
+rem Check the staging file too: an existing directory may be read-only.
+rem Redirection failures do not reliably update ERRORLEVEL in cmd.exe;
+rem branch on the command's failure directly. Never treat a directory as a
+rem staging file (later del cleanup would prompt to delete its contents).
+if exist "%cached%.part\" goto cache_write_failed
+(type nul >"%cached%.part") 2>nul || goto cache_write_failed
 set "asset=impeccable-windows-%arch%.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
 if not errorlevel 1 goto verify
-if not "%arch%"=="arm64" goto fail
+if not "%arch%"=="arm64" goto download_failed
 set "asset=impeccable-windows-x64.exe"
 set "url=%IMPECCABLE_DOWNLOAD_BASE%/engine-v%version%/%asset%"
 curl.exe -fsSL -o "%cached%.part" "%url%" >nul 2>nul
-if errorlevel 1 goto fail
+if errorlevel 1 goto download_failed
 
 :verify
 call :check_download
@@ -176,6 +185,28 @@ if not errorlevel 1 set "probe_ok=1"
 del "%probe_tmp%" >nul 2>nul
 exit /b 0
 
+:cache_directory_failed
+echo impeccable: engine %version% is not installed; cannot create cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:cache_write_failed
+echo impeccable: engine %version% is not installed; cannot write to cache directory: "%IMPECCABLE_HOME%\bin\%version%" 1>&2
+goto setup_failed
+
+:curl_missing
+echo impeccable: cannot download engine %version%; curl.exe is unavailable. 1>&2
+goto setup_failed
+
+:download_failed
+del "%cached%.part" >nul 2>nul
+echo impeccable: could not download engine %version% from %url%; check network access and the release URL. 1>&2
+
+:setup_failed
+echo Engine %version% setup needs network access and write permission to "%IMPECCABLE_HOME%\bin\%version%". 1>&2
+echo Run this launcher ("%~f0") with engine-probe in a terminal that has those permissions, then retry the original command. 1>&2
+echo Alternatively, set IMPECCABLE_HOME to a writable cache location, or IMPECCABLE_BIN to a preinstalled engine binary. 1>&2
+exit /b 127
+
 :fail
 del "%cached%.part" >nul 2>nul
 echo impeccable: no engine binary found (looked in %bin%, %cached%, PATH). 1>&2

tests/launcher-download.test.mjs

@@ -29,8 +29,29 @@ async function exercise(t, scenario) {
   const launcher = path.join(scripts, name);
   fs.copyFileSync(path.join(ROOT, 'skill/scripts', name), launcher);
   const cacheDir = path.join(cache, 'bin', '0.0.0-test');
+  if (scenario === 'cache-directory-failure') {
+    // A file where the cache parent belongs makes mkdir fail on every OS,
+    // including privileged test runners where chmod cannot deny writes.
+    fs.mkdirSync(cache);
+    fs.writeFileSync(path.join(cache, 'bin'), 'blocked');
+  }
+  if (scenario === 'cache-write-failure') {
+    fs.mkdirSync(cacheDir, { recursive: true });
+    if (WINDOWS) fs.mkdirSync(path.join(cacheDir, 'impeccable.exe.part'));
+  }
+  if (scenario === 'cache-readonly-file') {
+    fs.mkdirSync(cacheDir, { recursive: true });
+    const staging = path.join(cacheDir, 'impeccable.exe.part');
+    fs.writeFileSync(staging, 'read-only');
+    fs.chmodSync(staging, 0o444);
+  }
   const tools = path.join(root, 'tools');
   fs.mkdirSync(tools);
+  if (!WINDOWS && scenario === 'cache-write-failure') {
+    // The POSIX staging name contains the launcher's PID, so intercept the
+    // preceding mkdir to place a directory at precisely that file path.
+    fs.writeFileSync(path.join(tools, 'mkdir'), '#!/bin/sh\n/bin/mkdir "$@" || exit $?\n/bin/mkdir "$IMPECCABLE_HOME/bin/0.0.0-test/.impeccable.part.$PPID"\n', { mode: 0o755 });
+  }
   if (!WINDOWS && ['hash-failure', 'removed-during-hash'].includes(scenario)) {
     fs.writeFileSync(path.join(tools, 'shasum'),
       `#!/bin/sh\n${scenario === 'removed-during-hash' ? 'rm -f "$3"\n' : ''}printf '%s  %s\\n' '${HASH}' "$3"\nexit ${scenario === 'hash-failure' ? 1 : 0}\n`,
@@ -71,6 +92,10 @@ async function exercise(t, scenario) {
   const requests = [];
   const server = http.createServer((req, res) => {
     requests.push(req.url);
+    if (scenario === 'transport-failure') {
+      req.socket.destroy();
+      return;
+    }
     if (req.url.endsWith('.sha256')) {
       const part = fs.readdirSync(cacheDir).find(file => file.includes('.part'));
       if (scenario === 'removed') fs.unlinkSync(path.join(cacheDir, part));
@@ -78,6 +103,7 @@ async function exercise(t, scenario) {
       res.writeHead(scenario === 'no-sidecar' ? 404 : 200);
       res.end(scenario === 'empty-sidecar' ? '' : `${scenario === 'mismatch' ? '0'.repeat(64) : HASH}  engine\n`);
     } else {
+      if (scenario === 'download-failure') res.writeHead(404);
       res.end(scenario === 'empty-download' ? '' : PAYLOAD);
     }
   });
@@ -92,7 +118,7 @@ async function exercise(t, scenario) {
     IMPECCABLE_DOWNLOAD_BASE: `http://127.0.0.1:${server.address().port}`,
     ...(WINDOWS ? { SystemRoot: process.env.SystemRoot, ComSpec: COMSPEC, PROCESSOR_ARCHITECTURE: 'AMD64' } : {}),
   };
-  const result = await new Promise((resolve, reject) => {
+  const run = () => new Promise((resolve, reject) => {
     const child = WINDOWS
       ? spawn(COMSPEC, ['/d', '/s', '/c', `""${launcher}" /d /c echo verified-engine"`], { env, cwd: root, windowsVerbatimArguments: true, timeout: 20000 })
       : spawn('/bin/sh', [launcher], { env, cwd: root, timeout: 20000 });
@@ -103,9 +129,41 @@ async function exercise(t, scenario) {
     child.on('error', reject);
     child.on('close', (status, signal) => resolve({ status, signal, stdout, stderr }));
   });
+  const result = await run();
+  if (scenario === 'valid') {
+    const requestCount = requests.length;
+    const cachedResult = await run();
+    assert.equal(cachedResult.status, 0, cachedResult.stderr);
+    assert.match(cachedResult.stdout, /verified-engine/);
+    assert.equal(cachedResult.stderr, '', 'cached execution stays quiet');
+    assert.equal(requests.length, requestCount, 'subsequent runs use the cached engine without network');
+  }
   assert.equal(result.signal, null, JSON.stringify(result));
-  assert.equal(requests.filter(url => !url.endsWith('.sha256')).length, 1, 'one binary download, no verification retry loop');
-  return { ...result, files: fs.readdirSync(cacheDir), requests };
+  const cacheFailure = scenario.startsWith('cache-');
+  assert.equal(requests.filter(url => !url.endsWith('.sha256')).length, cacheFailure ? 0 : 1,
+    'cache failures do not attempt a download; other scenarios download once');
+  return { ...result, files: fs.existsSync(cacheDir) ? fs.readdirSync(cacheDir) : [], requests, cacheDir };
+}
+
+for (const scenario of ['cache-directory-failure', 'cache-write-failure', 'download-failure', 'transport-failure', ...(WINDOWS ? ['cache-readonly-file'] : [])]) {
+  test(`launcher explains ${scenario} and how to retry setup`, async t => {
+    const result = await exercise(t, scenario);
+    assert.equal(result.status, 127, JSON.stringify(result));
+    assert.doesNotMatch(result.stdout, /verified-engine/);
+    assert.match(result.stderr, /engine 0\.0\.0-test/);
+    assert.ok(result.stderr.includes(result.cacheDir), result.stderr);
+    assert.match(result.stderr, /engine-probe/);
+    assert.match(result.stderr, /IMPECCABLE_HOME/);
+    assert.match(result.stderr, /IMPECCABLE_BIN/);
+    if (['download-failure', 'transport-failure'].includes(scenario)) {
+      assert.match(result.stderr, /could not download/);
+      assert.match(result.stderr, /network/);
+      assert.deepEqual(result.files, [], 'failed downloads leave no staging files');
+      assert.equal(result.requests.length, 1, 'no verification without a download');
+    } else {
+      assert.match(result.stderr, scenario === 'cache-directory-failure' ? /cannot create/ : /cannot write/);
+    }
+  });
 }
 
 test('launcher downloads and runs a verified executable', async t => {