diff --git a/install.ps1 b/install.ps1
index a2aff0b69a..0b06cb3ea1 100644
--- a/install.ps1
+++ b/install.ps1
@@ -28,6 +28,14 @@ function Install-UnslothStudio {
         }
     }
 
+    function Clear-TauriInstallError {
+        param([string]$Message)
+        if ($TauriMode) {
+            Write-TauriLog "ERROR_CLEAR" $Message
+            [Console]::Error.WriteLine("[TAURI:ERROR_CLEAR] $Message")
+        }
+    }
+
     function Format-TauriDiagBool {
         param([bool]$Value)
         if ($Value) { return "true" }
@@ -86,7 +94,7 @@ function Install-UnslothStudio {
             [int]$Code = 1
         )
         if ($Code -eq 0) { $Code = 1 }
-        Write-TauriLog "ERROR" $Message
+        Write-TauriLog "ERROR_DEFAULT" $Message
         if (Get-Command Restore-StudioVenvRollback -CommandType Function -ErrorAction SilentlyContinue) {
             Restore-StudioVenvRollback
         }
@@ -485,7 +493,8 @@ function Install-UnslothStudio {
     # Full command output is shown only when --verbose / UNSLOTH_VERBOSE=1.
     function Invoke-InstallCommand {
         param(
-            [Parameter(Mandatory = $true)][ScriptBlock]$Command
+            [Parameter(Mandatory = $true)][ScriptBlock]$Command,
+            [string]$Label = "install command"
         )
         # Installer-pinned index installs (torch) must beat an inherited uv mirror (#6898):
         # for --default-index, clear the uv index env vars (restore in finally) and set
@@ -504,6 +513,7 @@ function Install-UnslothStudio {
         try {
             # Reset to avoid stale values from prior native commands.
             $global:LASTEXITCODE = 0
+            Write-TauriLog "OUTPUT_CLEAR" $Label
             if ($script:UnslothVerbose) {
                 # Merge stderr into stdout so progress/warning output stays visible
                 # without flipping $? on successful native commands (PS 5.1 treats
@@ -518,7 +528,13 @@ function Install-UnslothStudio {
                     Write-Host (Redact-InstallOutput $output) -ForegroundColor Red
                 }
             }
-            return [int]$LASTEXITCODE
+            $exitCode = [int]$LASTEXITCODE
+            if ($exitCode -eq 0) {
+                Clear-TauriInstallError "$Label recovered"
+            } else {
+                Write-TauriLog "ERROR_OUTPUT" "$Label failed (exit code $exitCode)"
+            }
+            return $exitCode
         } finally {
             $ErrorActionPreference = $prevEap
             if ($savedUvIndex) {
@@ -549,7 +565,7 @@ function Install-UnslothStudio {
         }
         $attempt = 1
         while ($true) {
-            $code = Invoke-InstallCommand $Command
+            $code = Invoke-InstallCommand -Command $Command -Label $Label
             if ($code -eq 0) { return 0 }
             if ($attempt -ge $maxAttempts) { return $code }
             substep ("retrying ""$Label"" after transient failure (attempt $($attempt + 1)/$maxAttempts, waiting ${delay}s)...") "Yellow"
@@ -1603,7 +1619,7 @@ exit 0
     if (-not (Test-Path -LiteralPath $VenvPython)) {
         step "venv" "creating Python $($DetectedPython.Version) virtual environment"
         substep "$VenvDir"
-        $venvExit = Invoke-InstallCommand { uv venv $VenvDir --python "$($DetectedPython.Path)" }
+        $venvExit = Invoke-InstallCommand -Label "create virtual environment" { uv venv $VenvDir --python "$($DetectedPython.Path)" }
         if ($venvExit -ne 0) {
             Write-Host "[ERROR] Failed to create virtual environment (exit code $venvExit)" -ForegroundColor Red
             return (Exit-InstallFailure "Failed to create virtual environment (exit code $venvExit)" $venvExit)
@@ -2375,7 +2391,7 @@ exit 0
         }
         if ($StudioLocalInstall) {
             substep "overlaying local repo (editable)..."
-            $overlayExit = Invoke-InstallCommand { uv pip install --python $VenvPython -e $RepoRoot --no-deps }
+            $overlayExit = Invoke-InstallCommand -Label "overlay local repo" { uv pip install --python $VenvPython -e $RepoRoot --no-deps }
             if ($overlayExit -ne 0) {
                 Write-Host "[ERROR] Failed to overlay local repo (exit code $overlayExit)" -ForegroundColor Red
                 return (Exit-InstallFailure "Failed to overlay local repo (exit code $overlayExit)" $overlayExit)
@@ -2464,7 +2480,7 @@ exit 0
 
         if ($StudioLocalInstall) {
             substep "overlaying local repo (editable)..."
-            $overlayExit = Invoke-InstallCommand { uv pip install --python $VenvPython -e $RepoRoot --no-deps }
+            $overlayExit = Invoke-InstallCommand -Label "overlay local repo" { uv pip install --python $VenvPython -e $RepoRoot --no-deps }
             if ($overlayExit -ne 0) {
                 Write-Host "[ERROR] Failed to overlay local repo (exit code $overlayExit)" -ForegroundColor Red
                 return (Exit-InstallFailure "Failed to overlay local repo (exit code $overlayExit)" $overlayExit)
@@ -2487,7 +2503,7 @@ exit 0
                 return (Exit-InstallFailure "Failed to install unsloth (exit code $baseInstallExit)" $baseInstallExit)
             }
             substep "overlaying local repo (editable)..."
-            $overlayExit = Invoke-InstallCommand { uv pip install --python $VenvPython -e $RepoRoot --no-deps }
+            $overlayExit = Invoke-InstallCommand -Label "overlay local repo" { uv pip install --python $VenvPython -e $RepoRoot --no-deps }
             if ($overlayExit -ne 0) {
                 Write-Host "[ERROR] Failed to overlay local repo (exit code $overlayExit)" -ForegroundColor Red
                 return (Exit-InstallFailure "Failed to overlay local repo (exit code $overlayExit)" $overlayExit)
@@ -2535,7 +2551,7 @@ exit 0
                     $visionSpec = if ($PinnedRocmVisionSpec) { $PinnedRocmVisionSpec } elseif ($ROCmGfxArch -and $torchvisionFloorMap -and $torchvisionFloorMap.ContainsKey($ROCmGfxArch)) { $torchvisionFloorMap[$ROCmGfxArch] } else { "torchvision" }
                     $audioSpec = if ($PinnedRocmAudioSpec) { $PinnedRocmAudioSpec } elseif ($ROCmGfxArch -and $torchaudioFloorMap -and $torchaudioFloorMap.ContainsKey($ROCmGfxArch)) { $torchaudioFloorMap[$ROCmGfxArch] } else { "torchaudio" }
                     substep "PyTorch flavor mismatch (installed $installedTorchTag, need ROCm) -- reinstalling correct build..." "Yellow"
-                    $torchFixExit = Invoke-InstallCommand { uv pip install --python $VenvPython --force-reinstall --default-index $ROCmIndexUrl $rocmSpec $visionSpec $audioSpec }
+                    $torchFixExit = Invoke-InstallCommand -Label "reinstall PyTorch (ROCm)" { uv pip install --python $VenvPython --force-reinstall --default-index $ROCmIndexUrl $rocmSpec $visionSpec $audioSpec }
                     if ($torchFixExit -ne 0) {
                         Write-Host "[ERROR] Failed to reinstall PyTorch with the correct ROCm build (exit code $torchFixExit)" -ForegroundColor Red
                         return (Exit-InstallFailure "Failed to reinstall PyTorch (ROCm) (exit code $torchFixExit)" $torchFixExit)
@@ -2544,7 +2560,7 @@ exit 0
                 } elseif ($expectedTorchTag -ne 'rocm') {
                     # CUDA: stale +cpu (or wrong cuXXX) against a CUDA index -> reinstall triplet.
                     substep "PyTorch flavor mismatch (installed $installedTorchTag, need $expectedTorchTag) -- reinstalling correct build..." "Yellow"
-                    $torchFixExit = Invoke-InstallCommand { uv pip install --python $VenvPython "torch>=2.4,<2.11.0" "torchvision>=0.19,<0.26.0" "torchaudio>=2.4,<2.11.0" --default-index $TorchIndexUrl --reinstall-package torch --reinstall-package torchvision --reinstall-package torchaudio }
+                    $torchFixExit = Invoke-InstallCommand -Label "reinstall PyTorch ($expectedTorchTag)" { uv pip install --python $VenvPython "torch>=2.4,<2.11.0" "torchvision>=0.19,<0.26.0" "torchaudio>=2.4,<2.11.0" --default-index $TorchIndexUrl --reinstall-package torch --reinstall-package torchvision --reinstall-package torchaudio }
                     if ($torchFixExit -ne 0) {
                         Write-Host "[ERROR] Failed to reinstall PyTorch with the correct CUDA build (exit code $torchFixExit)" -ForegroundColor Red
                         return (Exit-InstallFailure "Failed to reinstall PyTorch ($expectedTorchTag) (exit code $torchFixExit)" $torchFixExit)
@@ -2645,6 +2661,9 @@ exit 0
     # an inherited value would put llama.cpp in the wrong place.
     $previousUnslothStudioHome = $env:UNSLOTH_STUDIO_HOME
     $hadPreviousUnslothStudioHome = ($null -ne $previousUnslothStudioHome)
+    $previousTauriMode = $env:UNSLOTH_TAURI_MODE
+    $hadPreviousTauriMode = ($null -ne $previousTauriMode)
+    $env:UNSLOTH_TAURI_MODE = if ($TauriMode) { "1" } else { "0" }
     if ($StudioRedirectMode -eq 'env') {
         $env:UNSLOTH_STUDIO_HOME = $StudioHome
     } else {
@@ -2674,14 +2693,22 @@ exit 0
         } else {
             Remove-Item Env:UNSLOTH_STUDIO_HOME -ErrorAction SilentlyContinue
         }
+        if ($hadPreviousTauriMode) {
+            $env:UNSLOTH_TAURI_MODE = $previousTauriMode
+        } else {
+            Remove-Item Env:UNSLOTH_TAURI_MODE -ErrorAction SilentlyContinue
+        }
         Remove-Item Env:UNSLOTH_LOCAL_LLAMA_CPP_DIR -ErrorAction SilentlyContinue
         Remove-Item Env:UNSLOTH_INSTALL_ROLLBACK_MANAGED -ErrorAction SilentlyContinue
         Remove-Item Env:UNSLOTH_SETUP_PYTHON -ErrorAction SilentlyContinue
     }
     if ($setupExit -ne 0) {
-        Write-Host "[ERROR] unsloth studio setup failed (exit code $setupExit)" -ForegroundColor Red
+        if (-not $TauriMode) {
+            Write-Host "[ERROR] unsloth studio setup failed (exit code $setupExit)" -ForegroundColor Red
+        }
         return (Exit-InstallFailure "unsloth studio setup failed (exit code $setupExit)" $setupExit)
     }
+    Clear-TauriInstallError "studio setup completed"
 
     # ── Expose `unsloth` via a shim dir containing only unsloth.exe ──
     # We do NOT add the venv Scripts dir to PATH (it also holds python.exe
diff --git a/install.sh b/install.sh
index fece7b173b..376daa8fab 100755
--- a/install.sh
+++ b/install.sh
@@ -207,18 +207,37 @@ run_install_cmd() {
         # command's exit code across the pipe without relying on pipefail
         # (this script runs under plain sh).
         _rcf=$(mktemp)
-        { "$@" 2>&1; printf '%s' "$?" > "$_rcf"; } | _redact_install_output
+        tauri_stream_log stdout "OUTPUT_CLEAR" "$_label"
+        {
+            if "$@" 2>&1; then
+                _cmd_rc=0
+            else
+                _cmd_rc=$?
+            fi
+            printf '%s' "$_cmd_rc" > "$_rcf"
+        } | _redact_install_output
         _rc=$(cat "$_rcf" 2>/dev/null || echo 1)
         rm -f "$_rcf"
-        [ "${_rc:-1}" -eq 0 ] 2>/dev/null && return 0
+        _rc=${_rc:-1}
+        if [ "$_rc" -eq 0 ] 2>/dev/null; then
+            tauri_clear_install_error "$_label recovered"
+            return 0
+        fi
+        tauri_stream_log stdout "ERROR_OUTPUT" "$_label failed (exit code $_rc)"
         step "error" "$_label failed (exit code $_rc)" "$C_ERR" >&2
         return "$_rc"
     fi
     _log=$(mktemp)
-    "$@" >"$_log" 2>&1 && { rm -f "$_log"; return 0; }
+    tauri_stream_log stderr "OUTPUT_CLEAR" "$_label"
+    "$@" >"$_log" 2>&1 && {
+        rm -f "$_log"
+        tauri_clear_install_error "$_label recovered"
+        return 0
+    }
     _rc=$?
     step "error" "$_label failed (exit code $_rc)" "$C_ERR" >&2
     _redact_install_output "$_log" >&2
+    tauri_stream_log stderr "ERROR_OUTPUT" "$_label failed (exit code $_rc)"
     rm -f "$_log"
     return $_rc
 }
@@ -383,6 +402,34 @@ tauri_log() {
     fi
 }
 
+tauri_stream_log() {
+    _tsl_stream="$1"
+    _tsl_tag="$2"
+    shift 2
+    if [ "$TAURI_MODE" = true ]; then
+        if [ "$_tsl_stream" = stderr ]; then
+            printf '[TAURI:%s] %s\n' "$_tsl_tag" "$*" >&2
+        else
+            printf '[TAURI:%s] %s\n' "$_tsl_tag" "$*"
+        fi
+    fi
+}
+
+rollback_substep() {
+    if [ "$TAURI_MODE" = true ]; then
+        tauri_log "PROGRESS" "$1"
+    else
+        substep "$@"
+    fi
+}
+
+tauri_clear_install_error() {
+    if [ "$TAURI_MODE" = true ]; then
+        tauri_log "ERROR_CLEAR" "$1"
+        printf '[TAURI:ERROR_CLEAR] %s\n' "$1" >&2
+    fi
+}
+
 tauri_diag_marker() {
     _diag_gpu_branch="${1:-unknown}"
     _diag_torch_index_family="${2:-none}"
@@ -543,10 +590,10 @@ _restore_studio_venv_replacement() {
         _VENV_ROLLBACK_ACTIVE=false
         return 0
     }
-    substep "restoring previous environment after failed install..." "$C_WARN"
+    rollback_substep "restoring previous environment after failed install..." "$C_WARN"
     rm -rf "$_VENV_ROLLBACK_TARGET"
     if mv "$_VENV_ROLLBACK_DIR" "$_VENV_ROLLBACK_TARGET"; then
-        substep "restored previous environment"
+        rollback_substep "restored previous environment"
         _VENV_ROLLBACK_ACTIVE=false
         _VENV_ROLLBACK_DIR=""
     else
@@ -4055,6 +4102,7 @@ if [ -n "$VENV_ABS_BIN" ]; then
 fi
 
 if ! command -v bash >/dev/null 2>&1; then
+    tauri_log "ERROR" "bash is required to run studio setup"
     step "setup" "bash is required to run studio setup" "$C_ERR"
     substep "Please install bash and re-run install.sh"
     exit 1
@@ -4093,6 +4141,7 @@ if [ "$STUDIO_LOCAL_INSTALL" = true ]; then
     STUDIO_LOCAL_REPO="$_REPO_ROOT" \
     UNSLOTH_NO_TORCH="$SKIP_TORCH" \
     UNSLOTH_LOCAL_LLAMA_CPP_DIR="$_WITH_LLAMA_CPP_DIR" \
+    UNSLOTH_TAURI_MODE="$TAURI_MODE" \
     bash "$SETUP_SH" </dev/null || _SETUP_EXIT=$?
 else
     # Explicitly reset STUDIO_LOCAL_INSTALL / STUDIO_LOCAL_REPO so a stale
@@ -4108,9 +4157,14 @@ else
     STUDIO_LOCAL_REPO= \
     UNSLOTH_NO_TORCH="$SKIP_TORCH" \
     UNSLOTH_LOCAL_LLAMA_CPP_DIR="$_WITH_LLAMA_CPP_DIR" \
+    UNSLOTH_TAURI_MODE="$TAURI_MODE" \
     bash "$SETUP_SH" </dev/null || _SETUP_EXIT=$?
 fi
 
+if [ "$_SETUP_EXIT" -eq 0 ]; then
+    tauri_clear_install_error "studio setup completed"
+fi
+
 # ── Make 'unsloth' available via $_LOCAL_BIN (resolved earlier) ──
 # Env-mode: $_LOCAL_BIN is $STUDIO_HOME/bin; skip shell-rc PATH append so we
 # don't pollute the user's profile with a workspace-scoped path.
@@ -4166,7 +4220,11 @@ fi
 # PATH and shortcuts are already set up so the user can fix and retry.
 if [ "$_SETUP_EXIT" -ne 0 ]; then
     echo ""
-    step "error" "studio setup failed (exit code $_SETUP_EXIT)" "$C_ERR"
+    if [ "$TAURI_MODE" = true ]; then
+        tauri_log "ERROR_DEFAULT" "studio setup failed (exit code $_SETUP_EXIT)"
+    else
+        step "error" "studio setup failed (exit code $_SETUP_EXIT)" "$C_ERR"
+    fi
     echo ""
     exit "$_SETUP_EXIT"
 fi
diff --git a/studio/setup.ps1 b/studio/setup.ps1
index bb21ce2da6..4a87fd79e0 100644
--- a/studio/setup.ps1
+++ b/studio/setup.ps1
@@ -74,6 +74,20 @@ $script:NvccPath = $null
 $script:CudaToolkitRoot = $null
 $script:CudaArch = $null
 
+function Exit-SetupFailure {
+    param(
+        [Parameter(Mandatory = $true)][string]$Message,
+        [int]$Code = 1
+    )
+    if ($Code -eq 0) { $Code = 1 }
+    if (@("1", "true") -contains $env:UNSLOTH_TAURI_MODE) {
+        $singleLine = ($Message -replace '[\r\n]+', ' ').Trim()
+        [Console]::Out.WriteLine("[TAURI:ERROR] $singleLine")
+        [Console]::Out.Flush()
+    }
+    exit $Code
+}
+
 # Detect if running from pip install (no frontend/ dir in studio)
 $FrontendDir = Join-Path $ScriptDir "frontend"
 $OxcValidatorDir = Join-Path $ScriptDir "backend\core\data_recipe\oxc-validator"
@@ -851,7 +865,7 @@ function Ensure-BuildToolsForLlamaSourceBuild {
         Write-Host "        Manual install:" -ForegroundColor Red
         Write-Host '        1. winget install Microsoft.VisualStudio.2022.BuildTools --source winget' -ForegroundColor Yellow
         Write-Host '        2. Open Visual Studio Installer -> Modify -> check "Desktop development with C++"' -ForegroundColor Yellow
-        exit 1
+        Exit-SetupFailure "Visual Studio Build Tools are required for the llama.cpp source build"
     }
 }
 
@@ -1652,7 +1666,7 @@ if (-not $HasGit) {
     if (-not $HasGit) {
         Write-Host "[ERROR] Git is required but could not be installed automatically." -ForegroundColor Red
         Write-Host "        Install Git from https://git-scm.com/download/win and re-run." -ForegroundColor Red
-        exit 1
+        Exit-SetupFailure "Git is required but could not be installed automatically"
     }
     step "git" "$(git --version)"
 } else {
@@ -1821,7 +1835,7 @@ if (-not $NvccPath -and $IncompatibleToolkit) {
     Write-Host "========================================================================" -ForegroundColor Red
     Write-Host "[ERROR] CUDA source build cannot use the installed toolkit with this driver." -ForegroundColor Red
     Write-Host "========================================================================" -ForegroundColor Red
-    exit 1
+    Exit-SetupFailure "The installed CUDA toolkit is incompatible with the current driver"
 }
 
 # -- No toolkit at all: install via winget (only when a source build needs it) --
@@ -1893,7 +1907,7 @@ if (-not $NvccPath) {
     } else {
         Write-Host "        Install CUDA Toolkit from https://developer.nvidia.com/cuda-downloads" -ForegroundColor Yellow
     }
-    exit 1
+    Exit-SetupFailure "A compatible CUDA Toolkit could not be found or installed"
 }
 
 # -- Set CUDA env vars so cmake AND MSBuild can find the toolkit --
@@ -2043,7 +2057,7 @@ if (-not $IsPipInstall) {
         if (-not (Test-Path -LiteralPath $NodeOverride -PathType Container)) {
             Write-Host "ERROR: UNSLOTH_STUDIO_HOME/STUDIO_HOME=$NodeOverride does not exist." -ForegroundColor Red
             Write-Host "       Run install.ps1 to create the install root before 'unsloth studio update'." -ForegroundColor Red
-            exit 1
+            Exit-SetupFailure "UNSLOTH_STUDIO_HOME/STUDIO_HOME=$NodeOverride does not exist"
         }
         $NodeParent = (Resolve-Path -LiteralPath $NodeOverride).Path
         # An override pointing at the legacy default maps to the legacy sibling
@@ -2227,7 +2241,7 @@ if ($PythonOk) {
     if (-not $HasPython) {
         Write-Host "[ERROR] Python could not be installed automatically." -ForegroundColor Red
         Write-Host "        Install Python 3.12 from https://python.org/downloads/" -ForegroundColor Yellow
-        exit 1
+        Exit-SetupFailure "Python could not be installed automatically"
     }
     step "python" "$(python --version 2>&1)"
     $PythonOk = $true
@@ -2237,7 +2251,7 @@ if ($PythonOk) {
     Write-Host "[ERROR] No supported Python (3.11-3.13) found on this system." -ForegroundColor Red
     Write-Host "        py.exe could not locate -3.11/-3.12/-3.13 and `python` on PATH is unsupported." -ForegroundColor Yellow
     Write-Host "        Install Python 3.12 from https://python.org/downloads/" -ForegroundColor Yellow
-    exit 1
+    Exit-SetupFailure "No supported Python 3.11-3.13 was found"
 }
 
 # Add user-scheme Python Scripts dir to PATH (nt_user only, no venv fallback).
@@ -2319,7 +2333,7 @@ if ($NeedNodeForSetup) {
             if (-not (Test-Path -LiteralPath $nodeOwnedMarker) -and -not (Test-Path -LiteralPath $nodeMeta)) {
                 Write-Host "[ERROR] $NodeDir already exists and is not an Unsloth-owned Node install." -ForegroundColor Red
                 Write-Host "        Move it aside or choose an empty UNSLOTH_STUDIO_HOME before re-running." -ForegroundColor Yellow
-                exit 1
+                Exit-SetupFailure "$NodeDir is not an Unsloth-owned Node install"
             }
         }
         substep "installing isolated Node (system Node/npm left untouched)..."
@@ -2331,12 +2345,12 @@ if ($NeedNodeForSetup) {
         if ($nodeExit -eq 3) {
             Write-Host $nodeOut -ForegroundColor DarkGray
             step "node" "install blocked by another active Unsloth install" "Red"
-            exit 3
+            Exit-SetupFailure "Node install is blocked by another active Unsloth install" 3
         } elseif ($nodeExit -ne 0) {
             Write-Host $nodeOut -ForegroundColor DarkGray
             Write-Host "[ERROR] Could not install an isolated Node automatically." -ForegroundColor Red
             Write-Host "        Install Node >= 20.19 (with npm >= 11) from https://nodejs.org/ and re-run, or check your network." -ForegroundColor Yellow
-            exit 1
+            Exit-SetupFailure "Could not install an isolated Node runtime"
         }
         if ($NodeOverride -and (Test-Path -LiteralPath $NodeDir -PathType Container)) {
             New-Item -ItemType File -Force -Path (Join-Path $NodeDir ".unsloth-studio-owned") -ErrorAction SilentlyContinue | Out-Null
@@ -2456,7 +2470,7 @@ if ($NeedFrontendBuild -and -not $IsPipInstall) {
             Write-Host "[ERROR] npm install failed (exit code $npmExit)" -ForegroundColor Red
             Write-Host "   Try running 'npm install' manually in frontend/ to see errors" -ForegroundColor Yellow
             Show-NpmRegistryHint
-            exit 1
+            Exit-SetupFailure "Frontend dependency installation failed (exit code $npmExit)"
         }
     }
 
@@ -2467,7 +2481,7 @@ if ($NeedFrontendBuild -and -not $IsPipInstall) {
         $ErrorActionPreference = $prevEAP_npm
         foreach ($gi in $HiddenGitignores) { Rename-Item -Path "$gi._twbuild" -NewName (Split-Path $gi -Leaf) -Force -ErrorAction SilentlyContinue }
         Write-Host "[ERROR] npm run build failed (exit code $buildExit)" -ForegroundColor Red
-        exit 1
+        Exit-SetupFailure "Frontend build failed (exit code $buildExit)"
     }
     Pop-Location
     $ErrorActionPreference = $prevEAP_npm
@@ -2498,7 +2512,7 @@ if ((Test-Path $OxcValidatorDir) -and $NodeSource -ne "skip" -and (Get-Command n
         $ErrorActionPreference = $prevEAP_oxc
         Write-Host "[ERROR] OXC validator npm install failed (exit code $oxcInstallExit)" -ForegroundColor Red
         Show-NpmRegistryHint
-        exit 1
+        Exit-SetupFailure "OXC validator dependency installation failed (exit code $oxcInstallExit)"
     }
     Pop-Location
     $ErrorActionPreference = $prevEAP_oxc
@@ -2597,7 +2611,7 @@ if (-not $PythonCmd) {
     Write-Host "[ERROR] No standalone Python 3.11-3.13 found (conda Python is not supported)." -ForegroundColor Red
     Write-Host "        Install Python from https://python.org/downloads/ or via:" -ForegroundColor Yellow
     Write-Host "        winget install -e --id Python.Python.3.12" -ForegroundColor Yellow
-    exit 1
+    Exit-SetupFailure "No standalone Python 3.11-3.13 was found"
 }
 
 substep "Python found: $PythonCmd"
@@ -2630,12 +2644,12 @@ if ($_studioOverride) {
             Remove-Item -LiteralPath $_setupWriteProbe -Force -ErrorAction SilentlyContinue
         } catch {
             Write-Host "ERROR: $_studioOverrideVar=$StudioHome is not writable." -ForegroundColor Red
-            exit 1
+            Exit-SetupFailure "$_studioOverrideVar=$StudioHome is not writable"
         }
     } else {
         Write-Host "ERROR: $_studioOverrideVar=$_studioOverride does not exist." -ForegroundColor Red
         Write-Host "       Run install.ps1 to create the install root before 'unsloth studio update'." -ForegroundColor Red
-        exit 1
+        Exit-SetupFailure "$_studioOverrideVar=$_studioOverride does not exist"
     }
 } else {
     $StudioHome = Join-Path $env:USERPROFILE ".unsloth\studio"
@@ -2679,7 +2693,7 @@ function Assert-StudioOwnedOrAbsent {
         }
         Write-Host "[ERROR] $Path already exists and is not marked as an Unsloth-owned $Label." -ForegroundColor Red
         Write-Host "        Move it aside or choose an empty UNSLOTH_STUDIO_HOME before re-running." -ForegroundColor Yellow
-        exit 1
+        Exit-SetupFailure "$Label path is not an Unsloth-owned install: $Path"
     }
 }
 function Mark-StudioOwned {
@@ -2815,7 +2829,7 @@ if ((Test-Path -LiteralPath $VenvDir -PathType Container) -and -not $NoTorchMode
             substep "Stale venv detected ($reason)." "Yellow"
             Write-Host "   [ERROR] The existing Unsloth environment needs repair." -ForegroundColor Red
             Write-Host "           Re-run install.ps1 so it can replace the environment safely with rollback." -ForegroundColor Yellow
-            exit 1
+            Exit-SetupFailure "The existing Unsloth environment needs repair"
         }
         substep "Stale venv detected ($reason) -- rebuilding..." "Yellow"
         # why: mirror install.ps1 env-mode guard so an update against a custom
@@ -2829,14 +2843,14 @@ if ((Test-Path -LiteralPath $VenvDir -PathType Container) -and -not $NoTorchMode
         ) {
             Write-Host "[ERROR] $VenvDir already exists but does not look like an Unsloth Studio install." -ForegroundColor Red
             Write-Host "        Move it aside or choose an empty UNSLOTH_STUDIO_HOME before re-running." -ForegroundColor Yellow
-            exit 1
+            Exit-SetupFailure "$VenvDir is not an Unsloth Studio environment"
         }
         try {
             Remove-Item -LiteralPath $VenvDir -Recurse -Force -ErrorAction Stop
         } catch {
             Write-Host "   [ERROR] Could not remove stale venv: $($_.Exception.Message)" -ForegroundColor Red
             Write-Host "           Close any running Unsloth/Python processes and re-run setup." -ForegroundColor Red
-            exit 1
+            Exit-SetupFailure "Could not remove the stale environment at $VenvDir"
         }
     }
 }
@@ -2845,7 +2859,7 @@ if (-not (Test-Path -LiteralPath $VenvDir)) {
     Write-Host "[ERROR] Virtual environment not found at $VenvDir" -ForegroundColor Red
     Write-Host "        Run install.ps1 first to create the environment:" -ForegroundColor Yellow
     Write-Host "        irm https://unsloth.ai/install.ps1 | iex" -ForegroundColor Yellow
-    exit 1
+    Exit-SetupFailure "Virtual environment not found at $VenvDir"
 } else {
     substep "reusing existing virtual environment at $VenvDir"
     $_venvPyExe = Join-Path $VenvDir "Scripts\python.exe"
@@ -3216,7 +3230,7 @@ if (-not $ROCmIndexUrl -and ($CuTag -eq "cpu" -or $ROCmCpuFallback)) {
     if ($torchInstallExit -ne 0) {
         Write-Host "[FAILED] PyTorch install failed (exit code $torchInstallExit)" -ForegroundColor Red
         Write-Host (Redact-InstallOutput $output) -ForegroundColor Red
-        exit 1
+        Exit-SetupFailure "PyTorch installation failed (exit code $torchInstallExit)"
     }
 } elseif (-not $ROCmIndexUrl) {
     substep "installing PyTorch with CUDA support ($CuTag)..."
@@ -3248,7 +3262,7 @@ if (-not $ROCmIndexUrl -and ($CuTag -eq "cpu" -or $ROCmCpuFallback)) {
     if ($torchInstallExit -ne 0) {
         Write-Host "[FAILED] PyTorch CUDA install failed (exit code $torchInstallExit)" -ForegroundColor Red
         Write-Host (Redact-InstallOutput $output) -ForegroundColor Red
-        exit 1
+        Exit-SetupFailure "PyTorch CUDA installation failed (exit code $torchInstallExit)"
     }
 
     # Install Triton for Windows (enables torch.compile -- without it training can hang)
@@ -3284,7 +3298,7 @@ $ErrorActionPreference = $prevEAP
 if ($stackExit -ne 0) {
     Write-Host "[FAILED] Python dependency installation failed (exit code $stackExit)" -ForegroundColor Red
     Write-Host "   Re-run the installer or check the error above for details." -ForegroundColor Red
-    exit 1
+    Exit-SetupFailure "Python dependency installation failed (exit code $stackExit)"
 }
 
 } else {
@@ -3362,7 +3376,7 @@ foreach ($pkg in @("transformers==5.3.0", "huggingface_hub==1.8.0", "hf_xet==1.4
         Write-Host "[FAIL] Could not install $pkg into .venv_t5_530/" -ForegroundColor Red
         Write-Host (Redact-InstallOutput $output) -ForegroundColor Red
         $ErrorActionPreference = $prevEAP_t5
-        exit 1
+        Exit-SetupFailure "Could not install $pkg into .venv_t5_530"
     }
 }
 if ($script:UnslothVerbose) {
@@ -3397,7 +3411,7 @@ foreach ($pkg in @("transformers==5.5.0", "huggingface_hub==1.8.0", "hf_xet==1.4
         Write-Host "[FAIL] Could not install $pkg into .venv_t5_550/" -ForegroundColor Red
         Write-Host (Redact-InstallOutput $output) -ForegroundColor Red
         $ErrorActionPreference = $prevEAP_t5
-        exit 1
+        Exit-SetupFailure "Could not install $pkg into .venv_t5_550"
     }
 }
 if ($script:UnslothVerbose) {
@@ -3432,7 +3446,7 @@ foreach ($pkg in @("transformers==5.10.2", "huggingface_hub==1.8.0", "hf_xet==1.
         Write-Host "[FAIL] Could not install $pkg into .venv_t5_510/" -ForegroundColor Red
         Write-Host (Redact-InstallOutput $output) -ForegroundColor Red
         $ErrorActionPreference = $prevEAP_t5
-        exit 1
+        Exit-SetupFailure "Could not install $pkg into .venv_t5_510"
     }
 }
 if ($script:UnslothVerbose) {
@@ -3547,7 +3561,7 @@ if (-not $LlamaPr -and $LlamaPrForce -and $LlamaPrForce -match '^\d+$' -and [int
 if ($LlamaPr) {
     if ($LlamaPr -notmatch '^\d+$' -or [int]$LlamaPr -le 0) {
         Write-Host "[ERROR] UNSLOTH_LLAMA_PR=$LlamaPr is not a valid PR number" -ForegroundColor Red
-        exit 1
+        Exit-SetupFailure "UNSLOTH_LLAMA_PR=$LlamaPr is not a valid PR number"
     }
     step "llama.cpp" "UNSLOTH_LLAMA_PR=$LlamaPr -- will build from PR head" "Yellow"
     $ResolvedLlamaTag = "pr-$LlamaPr"
@@ -3563,7 +3577,7 @@ $LocalLlamaCppSrc = $env:UNSLOTH_LOCAL_LLAMA_CPP_DIR
 if ($LocalLlamaCppSrc) {
     if (-not (Test-Path -LiteralPath $LocalLlamaCppSrc -PathType Container)) {
         step "llama.cpp" "UNSLOTH_LOCAL_LLAMA_CPP_DIR does not exist: $LocalLlamaCppSrc" "Red"
-        exit 1
+        Exit-SetupFailure "UNSLOTH_LOCAL_LLAMA_CPP_DIR does not exist: $LocalLlamaCppSrc"
     }
     $ResolvedLocal = (Resolve-Path -LiteralPath $LocalLlamaCppSrc).Path
     # Reusing a local dir disables both the prebuilt download and the source
@@ -3594,7 +3608,7 @@ if ($LocalLlamaCppSrc) {
         # and leave Unsloth with no usable binary.
         if (-not $LocalLlamaServerFound) {
             step "llama.cpp" "no llama-server.exe under $ResolvedLocal (looked for .\llama-server.exe, .\build\bin and .\build\bin\Release) -- build llama.cpp there first, or drop --with-llama-cpp-dir" "Red"
-            exit 1
+            Exit-SetupFailure "No llama-server.exe was found under $ResolvedLocal"
         }
         # If the target is already a junction/symlink (e.g. a previous
         # --with-llama-cpp-dir run), delete only the link via DirectoryInfo.Delete().
@@ -3620,7 +3634,7 @@ if ($LocalLlamaCppSrc) {
             if (Test-Path -LiteralPath $LlamaCppDir) {
                 step "llama.cpp" "install blocked by active llama.cpp process" "Yellow"
                 substep "Close Unsloth or other llama.cpp users and retry" "Yellow"
-                exit 3
+                Exit-SetupFailure "llama.cpp install is blocked by an active llama.cpp process" 3
             }
         }
         cmd /c "mklink /J `"$LlamaCppDir`" `"$ResolvedLocal`"" 2>&1 | Out-Null
@@ -3762,7 +3776,7 @@ if ($LocalLlamaCppLinked) {
                 substep "Existing install was restored" "Yellow"
             }
             substep "Close Unsloth or other llama.cpp users and retry" "Yellow"
-            exit 3
+            Exit-SetupFailure "llama.cpp install is blocked by an active llama.cpp process" 3
         } elseif ($prebuiltExit -eq 4) {
             step "llama.cpp" "not enough disk space to install llama.cpp" "Yellow"
             Write-LlamaFailureLog -Output $prebuiltOutput
@@ -4025,7 +4039,7 @@ if ($LocalLlamaCppLinked) {
                 } else {
                     Write-Host "[ERROR] CMake 4.2+ is required to build llama.cpp with the Visual Studio 2026 generator, and no older Visual Studio toolchain was found to fall back to." -ForegroundColor Red
                     Write-Host "        Upgrade CMake from https://cmake.org/download/ and re-run, or use a prebuilt llama.cpp bundle." -ForegroundColor Red
-                    exit 1
+                    Exit-SetupFailure "CMake cannot drive the Visual Studio 2026 generator"
                 }
             }
         }
@@ -4532,5 +4546,5 @@ Write-Host ""
 # failure. Direct 'unsloth studio update' does not set SKIP_STUDIO_BASE,
 # so it keeps degraded installs successful.
 if ($script:LlamaCppDegraded -and $env:SKIP_STUDIO_BASE -eq "1") {
-    exit 1
+    Exit-SetupFailure "llama.cpp setup did not produce a usable server"
 }
diff --git a/studio/setup.sh b/studio/setup.sh
index b4088c15b6..1cad0e2dbe 100755
--- a/studio/setup.sh
+++ b/studio/setup.sh
@@ -67,6 +67,18 @@ fi
 step()    { printf "  ${C_DIM}%-15.15s${C_RST}${3:-$C_OK}%s${C_RST}\n" "$1" "$2"; }
 substep() { printf "  %-15s${2:-$C_DIM}%s${C_RST}\n" "" "$1"; }
 
+setup_fail() {
+    local exit_code=$1
+    shift
+    [ "$exit_code" -ne 0 ] || exit_code=1
+    local message
+    message=$(printf '%s' "$*" | tr '\r\n' '  ')
+    case "${UNSLOTH_TAURI_MODE:-0}" in
+        1|true) printf '[TAURI:ERROR] %s\n' "$message" ;;
+    esac
+    exit "$exit_code"
+}
+
 # ── Helper: can the controlling terminal actually be opened for reading? ──
 # `test -r` only checks permission bits, which look fine in containers and
 # systemd units where open() then fails with ENXIO. Probe with a real open.
@@ -173,7 +185,7 @@ _run_quiet() {
         exit_code=$?
         step "error" "$label failed (exit code $exit_code)" "$C_ERR" >&2
         if [ "$on_fail" = "exit" ]; then
-            exit "$exit_code"
+            setup_fail "$exit_code" "$label failed (exit code $exit_code)"
         else
             return "$exit_code"
         fi
@@ -182,7 +194,10 @@ _run_quiet() {
     local tmplog
     tmplog=$(mktemp) || {
         step "error" "Failed to create temporary file" "$C_ERR" >&2
-        [ "$on_fail" = "exit" ] && exit 1 || return 1
+        if [ "$on_fail" = "exit" ]; then
+            setup_fail 1 "Failed to create temporary file for $label"
+        fi
+        return 1
     }
 
     if "$@" >"$tmplog" 2>&1; then
@@ -196,7 +211,7 @@ _run_quiet() {
         rm -f "$tmplog"
 
         if [ "$on_fail" = "exit" ]; then
-            exit "$exit_code"
+            setup_fail "$exit_code" "$label failed (exit code $exit_code)"
         else
             return "$exit_code"
         fi
@@ -549,10 +564,14 @@ if [ -n "$_studio_override" ]; then
     if [ ! -d "$_studio_override" ]; then
         echo "ERROR: $_studio_override_var=$_studio_override does not exist." >&2
         echo "       Run install.sh to create the install root before 'unsloth studio update'." >&2
-        exit 1
+        setup_fail 1 "$_studio_override_var=$_studio_override does not exist"
     fi
-    [ -w "$_studio_override" ] || { echo "ERROR: $_studio_override_var=$_studio_override is not writable." >&2; exit 1; }
-    STUDIO_HOME="$(CDPATH= cd -P -- "$_studio_override" && pwd -P)" || exit 1
+    if [ ! -w "$_studio_override" ]; then
+        echo "ERROR: $_studio_override_var=$_studio_override is not writable." >&2
+        setup_fail 1 "$_studio_override_var=$_studio_override is not writable"
+    fi
+    STUDIO_HOME="$(CDPATH= cd -P -- "$_studio_override" && pwd -P)" ||
+        setup_fail 1 "Could not resolve $_studio_override_var=$_studio_override"
 else
     STUDIO_HOME="$HOME/.unsloth/studio"
 fi
@@ -598,7 +617,7 @@ _assert_studio_owned_or_absent() {
         fi
         echo "ERROR: $_aso_dir already exists and is not marked as an Unsloth-owned $_aso_label." >&2
         echo "       Move it aside or choose an empty UNSLOTH_STUDIO_HOME before re-running." >&2
-        exit 1
+        setup_fail 1 "$_aso_label path is not an Unsloth-owned install: $_aso_dir"
     fi
 }
 
@@ -716,12 +735,12 @@ elif [ "$NODE_SOURCE" = bundled ]; then
         step "node" "install blocked by another active Unsloth install" "$C_ERR"
         sed 's/^/   | /' "$_NODE_LOG" >&2; rm -f "$_NODE_LOG"
         substep "close other Unsloth installs and retry"
-        exit 3
+        setup_fail 3 "Node install is blocked by another active Unsloth install"
     elif [ "$_NODE_STATUS" -ne 0 ]; then
         step "node" "isolated Node install failed" "$C_ERR"
         sed 's/^/   | /' "$_NODE_LOG" >&2; rm -f "$_NODE_LOG"
         substep "install Node >= 20.19 (with npm >= 11) yourself and re-run, or check your network"
-        exit 1
+        setup_fail 1 "Could not install an isolated Node runtime"
     fi
     grep -Fq "already matches" "$_NODE_LOG" && verbose_substep "isolated Node already up to date"
     rm -f "$_NODE_LOG"
@@ -854,7 +873,7 @@ if [ "$_bun_install_ok" = false ]; then
     if [ "$_npm_install_rc" -ne 0 ]; then
         _suggest_npm_registry "$_FRONTEND_INSTALL_LOG"
         rm -f "$_FRONTEND_INSTALL_LOG"
-        exit "$_npm_install_rc"
+        setup_fail "$_npm_install_rc" "Frontend dependency installation failed (exit code $_npm_install_rc)"
     fi
 fi
 _CAPTURE_LOG=""
@@ -894,7 +913,7 @@ if [ -d "$_OXC_DIR" ] && [ "${NODE_SOURCE:-}" != skip ] && command -v npm &>/dev
     if [ "$_oxc_install_rc" -ne 0 ]; then
         _suggest_npm_registry "$_OXC_INSTALL_LOG"
         rm -f "$_OXC_INSTALL_LOG"
-        exit "$_oxc_install_rc"
+        setup_fail "$_oxc_install_rc" "OXC validator dependency installation failed (exit code $_oxc_install_rc)"
     fi
     rm -f "$_OXC_INSTALL_LOG"
     cd "$SCRIPT_DIR"
@@ -932,7 +951,7 @@ if [ ! -x "$VENV_DIR/bin/python" ]; then
             if ! run_quiet_no_exit "install Colab backend deps" pip install -q -r "$_COLAB_REQS_TMP"; then
                 rm -f "$_COLAB_REQS_TMP"
                 step "python" "Colab backend dependency install failed" "$C_ERR"
-                exit 1
+                setup_fail 1 "Colab backend dependency installation failed"
             fi
         else
             step "python" "no Colab backend dependencies resolved from requirements file" "$C_WARN"
@@ -943,7 +962,7 @@ if [ ! -x "$VENV_DIR/bin/python" ]; then
         step "python" "venv not found at $VENV_DIR" "$C_ERR"
         substep "Run install.sh first to create the environment:"
         substep "curl -fsSL https://unsloth.ai/install.sh | sh"
-        exit 1
+        setup_fail 1 "Virtual environment not found at $VENV_DIR"
     fi
 else
     source "$VENV_DIR/bin/activate"
@@ -1277,7 +1296,7 @@ fi
 if [ -n "$_LLAMA_PR" ]; then
     if ! [[ "$_LLAMA_PR" =~ ^[0-9]+$ ]] || [ "$_LLAMA_PR" -le 0 ]; then
         step "llama.cpp" "UNSLOTH_LLAMA_PR=$_LLAMA_PR is not a valid PR number" "$C_ERR"
-        exit 1
+        setup_fail 1 "UNSLOTH_LLAMA_PR=$_LLAMA_PR is not a valid PR number"
     fi
     step "llama.cpp" "UNSLOTH_LLAMA_PR=$_LLAMA_PR -- will build from PR head" "$C_WARN"
     _RESOLVED_LLAMA_TAG="pr-$_LLAMA_PR"
@@ -1313,7 +1332,7 @@ _LOCAL_LLAMA_CPP_LINKED=false
 if [ -n "${UNSLOTH_LOCAL_LLAMA_CPP_DIR:-}" ]; then
     if [ ! -d "$UNSLOTH_LOCAL_LLAMA_CPP_DIR" ]; then
         step "llama.cpp" "UNSLOTH_LOCAL_LLAMA_CPP_DIR does not exist: $UNSLOTH_LOCAL_LLAMA_CPP_DIR" "$C_ERR"
-        exit 1
+        setup_fail 1 "UNSLOTH_LOCAL_LLAMA_CPP_DIR does not exist: $UNSLOTH_LOCAL_LLAMA_CPP_DIR"
     fi
     _RESOLVED_LOCAL="$(CDPATH= cd -P -- "$UNSLOTH_LOCAL_LLAMA_CPP_DIR" && pwd -P)"
     # Canonicalize the install path the same way before comparing: _RESOLVED_LOCAL
@@ -1351,7 +1370,7 @@ if [ -n "${UNSLOTH_LOCAL_LLAMA_CPP_DIR:-}" ]; then
         # with no usable binary.
         if ! _has_local_llama_server "$_RESOLVED_LOCAL"; then
             step "llama.cpp" "no llama-server under $_RESOLVED_LOCAL (looked for ./llama-server and ./build/bin/llama-server) -- build llama.cpp there first, or drop --with-llama-cpp-dir" "$C_ERR"
-            exit 1
+            setup_fail 1 "No llama-server was found under $_RESOLVED_LOCAL"
         fi
         # A stale link from a previous --with-llama-cpp-dir run isn't Unsloth-owned
         # content; drop it before the ownership check so re-runs stay idempotent
@@ -1460,7 +1479,7 @@ else
             substep "existing install was restored"
         fi
         substep "close Unsloth or other llama.cpp users and retry"
-        exit 3
+        setup_fail 3 "llama.cpp install is blocked by an active llama.cpp process"
     elif [ "$_PREBUILT_STATUS" -eq 4 ]; then
         step "llama.cpp" "not enough disk space to install llama.cpp" "$C_WARN"
         print_llama_error_log "$_PREBUILT_LOG"
@@ -2217,5 +2236,5 @@ echo ""
 # successful -- the footer above already reports the limitation and Unsloth
 # is still usable for non-GGUF workflows.
 if [ "$_LLAMA_CPP_DEGRADED" = true ] && [ "${SKIP_STUDIO_BASE:-0}" = "1" ]; then
-    exit 1
+    setup_fail 1 "llama.cpp setup did not produce a usable server"
 fi
diff --git a/studio/src-tauri/src/diagnostics/mod.rs b/studio/src-tauri/src/diagnostics/mod.rs
index 998efc893e..3fdbac06dd 100644
--- a/studio/src-tauri/src/diagnostics/mod.rs
+++ b/studio/src-tauri/src/diagnostics/mod.rs
@@ -31,6 +31,10 @@ pub const TAIL_MAX_LINES: usize = 1000;
 pub const TAIL_MAX_BYTES: usize = 200 * 1024;
 pub const REPORT_MAX_BYTES: usize = 1024 * 1024;
 
+pub(crate) fn redact_for_display(text: &str) -> String {
+    redaction::redact_text(text, &mut redaction::RedactionReport::default())
+}
+
 pub(crate) const MAX_STATE_ITEMS: usize = 200;
 pub(crate) const MAX_PHASE_LINE_BYTES: usize = 16 * 1024;
 pub(crate) const FOOTER_BUDGET_BYTES: usize = 8 * 1024;
diff --git a/studio/src-tauri/src/diagnostics/redaction.rs b/studio/src-tauri/src/diagnostics/redaction.rs
index 0c7a92944a..bd36f9254e 100644
--- a/studio/src-tauri/src/diagnostics/redaction.rs
+++ b/studio/src-tauri/src/diagnostics/redaction.rs
@@ -16,6 +16,8 @@ pub(crate) fn redact_text(text: &str, report: &mut RedactionReport) -> String {
     }
     out = replace_regex(private_key_re(), &out, "<redacted private key>", report);
     out = replace_regex(url_credentials_re(), &out, "$1<redacted>@", report);
+    out = replace_regex(url_query_value_re(), &out, "$1=<redacted>", report);
+    out = replace_regex(url_fragment_re(), &out, "$1#<redacted>", report);
     out = replace_regex(auth_header_re(), &out, "$1: <redacted>", report);
     out = replace_regex(cookie_re(), &out, "$1: <redacted>", report);
     out = replace_regex(token_re(), &out, "<redacted token>", report);
@@ -110,6 +112,16 @@ fn url_credentials_re() -> &'static Regex {
     RE.get_or_init(|| Regex::new(r"(?i)\b([a-z][a-z0-9+.-]*://)[^/\s:@]+(:[^/\s@]*)?@").unwrap())
 }
 
+fn url_query_value_re() -> &'static Regex {
+    static RE: OnceLock<Regex> = OnceLock::new();
+    RE.get_or_init(|| Regex::new(r"([?&][^=\s&`]+)=[^&#\s`]+").unwrap())
+}
+
+fn url_fragment_re() -> &'static Regex {
+    static RE: OnceLock<Regex> = OnceLock::new();
+    RE.get_or_init(|| Regex::new(r"(?i)(https?://[^\s`#]+)#[^\s`]+").unwrap())
+}
+
 fn auth_header_re() -> &'static Regex {
     static RE: OnceLock<Regex> = OnceLock::new();
     RE.get_or_init(|| Regex::new(r"(?i)\b(authorization|proxy-authorization)\s*[:=]\s*(bearer|basic)?\s*[A-Za-z0-9._~+/=-]+").unwrap())
@@ -183,6 +195,7 @@ mod tests {
             "API_KEY=secret123\n",
             "native_path_lease=abc.DEF_123\n",
             "url=https://user:pass@example.com/path\n",
+            "signed=https://example.com/object?X-Amz-Signature=presignedvalue987&version=1#fragmentsecret\n",
             "email=alex@example.com\n",
             "path=/Users/alex/.unsloth/studio/logs/install.log\n",
             "win=C:\\Users\\Alex\\.unsloth\\studio\\logs\\install.log\n",
@@ -198,6 +211,9 @@ mod tests {
         assert!(!redacted.contains("abc.DEF_123"));
         assert!(redacted.contains("native_path_lease=<redacted native path lease>"));
         assert!(redacted.contains("https://<redacted>@example.com/path"));
+        assert!(!redacted.contains("presignedvalue987"));
+        assert!(!redacted.contains("fragmentsecret"));
+        assert!(redacted.contains("?X-Amz-Signature=<redacted>&version=<redacted>#<redacted>"));
         assert!(!redacted.contains("alex@example.com"));
         assert!(redacted.contains("<studio_home>"));
         assert!(!redacted.contains("PRIVATE KEY-----\nabc"));
diff --git a/studio/src-tauri/src/install.rs b/studio/src-tauri/src/install.rs
index 024b730735..d7226bf901 100644
--- a/studio/src-tauri/src/install.rs
+++ b/studio/src-tauri/src/install.rs
@@ -1,6 +1,7 @@
 use crate::diagnostics::{self, AttemptLog, DiagnosticsState};
 use log::{error, info, warn};
 use process_wrap::std::*;
+use std::collections::VecDeque;
 use std::io::BufRead;
 use std::path::{Path, PathBuf};
 use std::process::{Command, ExitStatus, Stdio};
@@ -38,6 +39,160 @@ pub fn new_install_state() -> InstallState {
 
 use crate::process::trim_line_endings;
 
+const FAILURE_CONTEXT_LINES: usize = 8;
+const FAILURE_CONTEXT_LINE_BYTES: usize = 1_000;
+
+fn generic_failure_message(code: i32) -> String {
+    format!(
+        "Installation failed with exit code {}. Open the installer logs for details.",
+        code
+    )
+}
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum InstallOutputStream {
+    Stdout,
+    Stderr,
+}
+
+struct InstallOutputLine {
+    stream: InstallOutputStream,
+    text: String,
+}
+
+#[derive(Default)]
+struct InstallFailureContext {
+    explicit_error: Option<String>,
+    explicit_error_stream: Option<InstallOutputStream>,
+    default_error: Option<String>,
+    output_tail: VecDeque<InstallOutputLine>,
+}
+
+impl InstallFailureContext {
+    fn observe_stdout(&mut self, text: &str) -> bool {
+        if text.starts_with("[TAURI:ERROR_CLEAR] ") {
+            self.clear_failure(InstallOutputStream::Stdout);
+            return true;
+        }
+        if text.starts_with("[TAURI:OUTPUT_CLEAR] ") {
+            self.clear_stream(InstallOutputStream::Stdout);
+            return true;
+        }
+        if let Some(message) = text.strip_prefix("[TAURI:ERROR] ") {
+            let message = message.trim();
+            if !message.is_empty() {
+                self.explicit_error = Some(Self::bounded_line(message));
+                self.explicit_error_stream = Some(InstallOutputStream::Stdout);
+            }
+            return false;
+        }
+        if let Some(message) = text.strip_prefix("[TAURI:ERROR_OUTPUT] ") {
+            self.capture_output_error(InstallOutputStream::Stdout, message);
+            return true;
+        }
+        if let Some(message) = text.strip_prefix("[TAURI:ERROR_DEFAULT] ") {
+            let message = message.trim();
+            if !message.is_empty() {
+                self.default_error = Some(Self::bounded_line(message));
+            }
+            return true;
+        }
+        if !text.starts_with("[TAURI:") {
+            self.push_output(InstallOutputStream::Stdout, text);
+        }
+        false
+    }
+
+    fn observe_stderr(&mut self, text: &str) -> bool {
+        if text.starts_with("[TAURI:ERROR_CLEAR] ") {
+            self.clear_failure(InstallOutputStream::Stderr);
+            return true;
+        }
+        if text.starts_with("[TAURI:OUTPUT_CLEAR] ") {
+            self.clear_stream(InstallOutputStream::Stderr);
+            return true;
+        }
+        if let Some(message) = text.strip_prefix("[TAURI:ERROR_OUTPUT] ") {
+            self.capture_output_error(InstallOutputStream::Stderr, message);
+            return true;
+        }
+        self.push_output(InstallOutputStream::Stderr, text);
+        false
+    }
+
+    fn capture_output_error(&mut self, stream: InstallOutputStream, fallback: &str) {
+        let fallback = fallback.trim();
+        let detail = self
+            .output_tail
+            .iter()
+            .rev()
+            .find(|line| line.stream == stream)
+            .map(|line| line.text.as_str());
+        if let Some(error) = match (fallback.is_empty(), detail) {
+            (_, Some(detail)) if fallback == detail => Some(detail.to_owned()),
+            (false, Some(detail)) => Some(Self::bounded_line(&format!("{fallback}: {detail}"))),
+            (false, None) => Some(Self::bounded_line(fallback)),
+            (true, Some(detail)) => Some(detail.to_owned()),
+            (true, None) => None,
+        } {
+            self.explicit_error = Some(error);
+            self.explicit_error_stream = Some(stream);
+        }
+    }
+
+    fn clear_failure(&mut self, stream: InstallOutputStream) {
+        if self.explicit_error_stream == Some(stream) {
+            self.explicit_error = None;
+            self.explicit_error_stream = None;
+        }
+        if stream == InstallOutputStream::Stdout {
+            self.default_error = None;
+        }
+        self.clear_stream(stream);
+    }
+
+    fn clear_stream(&mut self, stream: InstallOutputStream) {
+        self.output_tail.retain(|line| line.stream != stream);
+    }
+
+    fn push_output(&mut self, stream: InstallOutputStream, text: &str) {
+        let text = text.trim();
+        if text.is_empty() {
+            return;
+        }
+        let text = Self::bounded_line(text);
+        self.output_tail
+            .push_back(InstallOutputLine { stream, text });
+        while self.output_tail.len() > FAILURE_CONTEXT_LINES {
+            self.output_tail.pop_front();
+        }
+    }
+
+    fn bounded_line(text: &str) -> String {
+        let mut text = diagnostics::redact_for_display(text);
+        let boundary =
+            diagnostics::valid_utf8_boundary(&text, text.len().min(FAILURE_CONTEXT_LINE_BYTES));
+        text.truncate(boundary);
+        text
+    }
+
+    fn message(&self, code: i32) -> String {
+        let detail = self
+            .explicit_error
+            .as_deref()
+            .or(self.default_error.as_deref())
+            .or_else(|| self.output_tail.back().map(|line| line.text.as_str()));
+        match detail {
+            Some(detail) => format!("Installation failed: {}", detail),
+            None => generic_failure_message(code),
+        }
+    }
+}
+
+fn is_elevation_request(code: i32, packages: &[String]) -> bool {
+    code == 2 && !packages.is_empty()
+}
+
 // ── Script Resolution ──
 
 /// Returns (script_path, args) depending on dev vs production mode.
@@ -232,7 +387,7 @@ fn spawn_script(
 // ── Stream ──
 
 /// Spawns reader threads for stdout/stderr.
-/// Parses [TAURI:*] lines from stdout for structured events.
+/// Parses structured events from stdout and failure controls from both streams.
 fn stream_output(
     app: &AppHandle,
     state: &InstallState,
@@ -241,14 +396,19 @@ fn stream_output(
     attempt: AttemptLog,
     stdout: Option<std::process::ChildStdout>,
     stderr: Option<std::process::ChildStderr>,
-) -> Vec<std::thread::JoinHandle<()>> {
+) -> (
+    Vec<std::thread::JoinHandle<()>>,
+    Arc<Mutex<InstallFailureContext>>,
+) {
     let mut threads = Vec::new();
+    let failure_context = Arc::new(Mutex::new(InstallFailureContext::default()));
 
     if let Some(out) = stdout {
         let app_clone = app.clone();
         let state_clone = Arc::clone(state);
         let diagnostics_clone = diagnostics.clone();
         let attempt_clone = attempt.clone();
+        let failure_context_clone = Arc::clone(&failure_context);
         threads.push(std::thread::spawn(move || {
             let mut reader = std::io::BufReader::new(out);
             let mut buf = Vec::new();
@@ -259,6 +419,14 @@ fn stream_output(
                     Ok(_) => {
                         let text = String::from_utf8_lossy(trim_line_endings(&buf)).into_owned();
                         diagnostics::append_phase_line(&attempt_clone.handle, "stdout", &text);
+                        let is_failure_control = failure_context_clone
+                            .lock()
+                            .map(|mut context| context.observe_stdout(&text))
+                            .unwrap_or(false);
+                        if is_failure_control {
+                            info!("[install][stdout] {}", text);
+                            continue;
+                        }
                         // Parse structured Tauri protocol lines
                         if let Some(packages) = text.strip_prefix("[TAURI:NEED_SUDO] ") {
                             let pkgs: Vec<String> =
@@ -314,6 +482,7 @@ fn stream_output(
     if let Some(err) = stderr {
         let app_clone = app.clone();
         let attempt_clone = attempt.clone();
+        let failure_context_clone = Arc::clone(&failure_context);
         threads.push(std::thread::spawn(move || {
             let mut reader = std::io::BufReader::new(err);
             let mut buf = Vec::new();
@@ -324,6 +493,14 @@ fn stream_output(
                     Ok(_) => {
                         let text = String::from_utf8_lossy(trim_line_endings(&buf)).into_owned();
                         diagnostics::append_phase_line(&attempt_clone.handle, "stderr", &text);
+                        let is_failure_control = failure_context_clone
+                            .lock()
+                            .map(|mut context| context.observe_stderr(&text))
+                            .unwrap_or(false);
+                        if is_failure_control {
+                            info!("[install][stderr] {}", text);
+                            continue;
+                        }
                         warn!("[install][stderr] {}", text);
                         let _ = app_clone.emit(event_mode.progress_event(), &text);
                     }
@@ -336,7 +513,7 @@ fn stream_output(
         }));
     }
 
-    threads
+    (threads, failure_context)
 }
 
 // ── Wait & Finalize ──
@@ -457,7 +634,7 @@ fn run_install_with_event_mode(
             return Err(msg);
         }
     };
-    let threads = stream_output(
+    let (threads, failure_context) = stream_output(
         &app,
         &state,
         event_mode,
@@ -490,12 +667,12 @@ fn run_install_with_event_mode(
         }
         Ok((status, intentional)) => {
             let code = status.code().unwrap_or(-1);
-            if code == 2 {
+            let packages = state
+                .lock()
+                .map(|install| install.needed_packages.clone())
+                .unwrap_or_default();
+            if is_elevation_request(code, &packages) {
                 // Script needs elevated package install — report to frontend
-                let packages = state
-                    .lock()
-                    .map(|i| i.needed_packages.clone())
-                    .unwrap_or_default();
                 diagnostics::record_elevation_packages(&diagnostics, &attempt, &packages);
                 diagnostics::finish_attempt(
                     &diagnostics,
@@ -508,7 +685,10 @@ fn run_install_with_event_mode(
                 let _ = app.emit(event_mode.needs_elevation_event(), &packages);
                 Err("NEEDS_ELEVATION".to_string())
             } else {
-                let msg = format!("Installer exited with code {}", code);
+                let msg = failure_context
+                    .lock()
+                    .map(|context| context.message(code))
+                    .unwrap_or_else(|_| generic_failure_message(code));
                 diagnostics::finish_attempt(
                     &diagnostics,
                     &attempt,
@@ -896,5 +1076,211 @@ mod tests {
             "repair-needs-elevation"
         );
         assert!(!InstallEventMode::Repair.emit_terminal_events());
+        assert!(!is_elevation_request(2, &[]));
+        assert!(is_elevation_request(2, &["cmake".to_string()]));
+        assert!(!is_elevation_request(1, &["cmake".to_string()]));
+    }
+
+    #[test]
+    fn explicit_installer_error_beats_stderr_noise() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("[TAURI:ERROR] Failed to install PyTorch");
+        context.observe_stderr("rollback cleanup failed");
+        assert_eq!(
+            context.message(7),
+            "Installation failed: Failed to install PyTorch"
+        );
+    }
+
+    #[test]
+    fn command_error_includes_preceding_output_from_the_same_stream() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("unrelated stdout");
+        context.observe_stderr("resolver error: no space left on device");
+        assert!(context.observe_stderr("[TAURI:ERROR_OUTPUT] install unsloth failed (exit code 1)"));
+        context.observe_stdout("[TAURI:ERROR_DEFAULT] Failed to install unsloth");
+        assert_eq!(
+            context.message(1),
+            "Installation failed: install unsloth failed (exit code 1): resolver error: no space left on device"
+        );
+    }
+
+    #[test]
+    fn command_error_without_output_uses_its_fallback() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("unrelated output from an earlier step");
+        assert!(context.observe_stdout("[TAURI:OUTPUT_CLEAR] create venv"));
+        assert!(context.observe_stdout("[TAURI:ERROR_OUTPUT] create venv failed (exit code 2)"));
+        assert_eq!(
+            context.message(2),
+            "Installation failed: create venv failed (exit code 2)"
+        );
+    }
+
+    #[test]
+    fn recovered_retry_clears_stale_installer_error() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stderr("ERROR: transient PyTorch download failure");
+        assert!(context.observe_stderr("[TAURI:ERROR_OUTPUT] install PyTorch failed (exit code 1)"));
+        assert!(context.observe_stdout("[TAURI:ERROR_CLEAR] install PyTorch recovered after retry"));
+        assert!(context.observe_stderr("[TAURI:ERROR_CLEAR] install PyTorch recovered after retry"));
+        context.observe_stderr("ERROR: studio setup failed");
+        let message = context.message(7);
+        assert!(message.contains("studio setup failed"));
+        assert!(!message.contains("install PyTorch"));
+        assert!(!message.contains("transient PyTorch"));
+    }
+
+    #[test]
+    fn recovery_clear_is_order_independent_across_streams() {
+        let mut context = InstallFailureContext::default();
+        assert!(context.observe_stdout("[TAURI:ERROR_CLEAR] install PyTorch recovered"));
+        context.observe_stderr("ERROR: transient PyTorch download failure");
+        assert!(context.observe_stderr("[TAURI:ERROR_OUTPUT] install PyTorch failed (exit code 1)"));
+        assert!(context.observe_stderr("[TAURI:ERROR_CLEAR] install PyTorch recovered"));
+        context.observe_stdout("[TAURI:ERROR] later setup failure");
+        assert!(context.observe_stderr("[TAURI:ERROR_CLEAR] delayed recovery clear"));
+        assert_eq!(
+            context.message(1),
+            "Installation failed: later setup failure"
+        );
+    }
+
+    #[test]
+    fn successful_fallback_clears_unstructured_stderr() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stderr("bitsandbytes pre-release install failed");
+        assert!(context.observe_stderr("[TAURI:ERROR_CLEAR] bitsandbytes pypi fallback recovered"));
+        context.observe_stderr("mkdir: cannot create directory: Permission denied");
+        assert_eq!(
+            context.message(1),
+            "Installation failed: mkdir: cannot create directory: Permission denied"
+        );
+    }
+
+    #[test]
+    fn setup_failure_uses_explicit_producer_error_before_default() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("CMake not found -- installing via winget");
+        context.observe_stdout("[TAURI:ERROR] UNSLOTH_LLAMA_PR=invalid is not a valid PR number");
+        assert!(context.observe_stdout("[TAURI:ERROR_DEFAULT] studio setup failed (exit code 4)"));
+        assert_eq!(
+            context.message(4),
+            "Installation failed: UNSLOTH_LLAMA_PR=invalid is not a valid PR number"
+        );
+    }
+
+    #[test]
+    fn setup_failure_uses_default_without_specific_output() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("Finishing setup");
+        assert!(context.observe_stdout("[TAURI:ERROR_DEFAULT] studio setup failed (exit code 4)"));
+        context.observe_stderr("restored previous environment");
+        assert_eq!(
+            context.message(4),
+            "Installation failed: studio setup failed (exit code 4)"
+        );
+    }
+
+    #[test]
+    fn explicit_setup_error_survives_optional_output_and_footer() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("[TAURI:ERROR] llama.cpp setup did not produce a usable server");
+        context.observe_stderr("whisper.cpp source build failed (exit code 1)");
+        context.observe_stdout(
+            "whisper.cpp    prebuilt install failed; browser and Transformers dictation remain available",
+        );
+        for index in 0..10 {
+            context.observe_stdout(&format!("setup footer line {index}"));
+        }
+        assert!(context.observe_stdout("[TAURI:ERROR_DEFAULT] studio setup failed (exit code 1)"));
+        assert_eq!(
+            context.message(1),
+            "Installation failed: llama.cpp setup did not produce a usable server"
+        );
+    }
+
+    #[test]
+    fn setup_default_outranks_nonfatal_failure_output() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("long paths failed to enable");
+        context.observe_stderr("Triton install failed; torch.compile may not work");
+        assert!(context.observe_stdout("[TAURI:ERROR_DEFAULT] studio setup failed (exit code 3)"));
+        assert_eq!(
+            context.message(3),
+            "Installation failed: studio setup failed (exit code 3)"
+        );
+    }
+
+    #[test]
+    fn latest_output_is_used_without_structured_context() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stderr("first diagnostic");
+        context.observe_stderr("mv: cannot move build: Permission denied");
+        assert_eq!(
+            context.message(1),
+            "Installation failed: mv: cannot move build: Permission denied"
+        );
+    }
+
+    #[test]
+    fn structured_rollback_progress_does_not_replace_failure_output() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stderr("ln: cannot create symbolic link: Permission denied");
+        context.observe_stdout(
+            "[TAURI:PROGRESS] restoring previous environment after failed install...",
+        );
+        context.observe_stdout("[TAURI:PROGRESS] restored previous environment");
+        assert_eq!(
+            context.message(1),
+            "Installation failed: ln: cannot create symbolic link: Permission denied"
+        );
+    }
+
+    #[test]
+    fn installer_exit_code_is_not_duplicated() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout("[TAURI:ERROR] Failed to install PyTorch (exit code 7)");
+        let message = context.message(7);
+        assert_eq!(
+            message,
+            "Installation failed: Failed to install PyTorch (exit code 7)"
+        );
+        assert_eq!(message.matches("exit code 7").count(), 1);
+    }
+
+    #[test]
+    fn stderr_fallback_redacts_secrets() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stderr("ERROR: download failed for https://user:pass@example.com/package");
+        let message = context.message(1);
+        assert!(message.contains("ERROR: download failed"));
+        assert!(message.contains("https://<redacted>@example.com/package"));
+        assert!(!message.contains("user:pass"));
+    }
+
+    #[test]
+    fn failure_context_is_bounded_and_utf8_safe() {
+        let mut context = InstallFailureContext::default();
+        context.observe_stdout(&format!(
+            "[TAURI:ERROR] {}https://user:secret@example.com/package",
+            "é".repeat(500)
+        ));
+        for index in 0..20 {
+            context.observe_stderr(&format!("{index}: {}", "é".repeat(1_000)));
+        }
+        let explicit_error = context.explicit_error.as_ref().unwrap();
+        assert!(explicit_error.len() <= FAILURE_CONTEXT_LINE_BYTES);
+        assert!(explicit_error.is_char_boundary(explicit_error.len()));
+        assert!(!explicit_error.contains("secret"));
+        assert_eq!(context.output_tail.len(), FAILURE_CONTEXT_LINES);
+        assert!(context
+            .output_tail
+            .iter()
+            .all(|line| line.text.len() <= FAILURE_CONTEXT_LINE_BYTES));
+        assert!(context
+            .output_tail
+            .iter()
+            .all(|line| line.text.is_char_boundary(line.text.len())));
     }
 }
diff --git a/tests/sh/test_install_rollback_lifecycle.sh b/tests/sh/test_install_rollback_lifecycle.sh
index d1ccae8e19..b0e6183fb4 100644
--- a/tests/sh/test_install_rollback_lifecycle.sh
+++ b/tests/sh/test_install_rollback_lifecycle.sh
@@ -32,6 +32,7 @@ run_signal_case() {
     {
         printf '%s\n' 'set -e'
         printf '%s\n' 'substep() { :; }'
+        printf '%s\n' 'rollback_substep() { substep "$@"; }'
         printf '%s\n' 'C_WARN=""'
         printf "STUDIO_HOME='%s'\n" "$_case_dir"
         printf "VENV_DIR='%s/unsloth_studio'\n" "$_case_dir"
@@ -77,6 +78,7 @@ START_BOUNDARY_HARNESS="$START_BOUNDARY_DIR/harness.sh"
 {
     printf '%s\n' 'set -e'
     printf '%s\n' 'substep() { :; }'
+    printf '%s\n' 'rollback_substep() { substep "$@"; }'
     printf '%s\n' 'C_WARN=""'
     printf "STUDIO_HOME='%s'\n" "$START_BOUNDARY_DIR"
     printf "VENV_DIR='%s/unsloth_studio'\n" "$START_BOUNDARY_DIR"
@@ -102,6 +104,7 @@ COMMIT_BOUNDARY_HARNESS="$COMMIT_BOUNDARY_DIR/harness.sh"
 {
     printf '%s\n' 'set -e'
     printf '%s\n' 'substep() { :; }'
+    printf '%s\n' 'rollback_substep() { substep "$@"; }'
     printf '%s\n' 'C_WARN=""'
     printf "STUDIO_HOME='%s'\n" "$COMMIT_BOUNDARY_DIR"
     printf "VENV_DIR='%s/unsloth_studio'\n" "$COMMIT_BOUNDARY_DIR"
@@ -131,6 +134,7 @@ PRUNE_HARNESS="$PRUNE_DIR/harness.sh"
 {
     printf '%s\n' 'set -e'
     printf '%s\n' 'substep() { :; }'
+    printf '%s\n' 'rollback_substep() { substep "$@"; }'
     printf '%s\n' 'C_WARN=""'
     printf "STUDIO_HOME='%s'\n" "$PRUNE_DIR"
     printf "VENV_DIR='%s/unsloth_studio'\n" "$PRUNE_DIR"
diff --git a/tests/sh/test_tauri_retry_failure_context.sh b/tests/sh/test_tauri_retry_failure_context.sh
new file mode 100755
index 0000000000..e9034e8e54
--- /dev/null
+++ b/tests/sh/test_tauri_retry_failure_context.sh
@@ -0,0 +1,307 @@
+#!/bin/bash
+# SPDX-License-Identifier: AGPL-3.0-only
+# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+INSTALL_SH="$SCRIPT_DIR/../../install.sh"
+INSTALL_PS1="$SCRIPT_DIR/../../install.ps1"
+SETUP_SH="$SCRIPT_DIR/../../studio/setup.sh"
+SETUP_PS1="$SCRIPT_DIR/../../studio/setup.ps1"
+
+_FUNC_FILE=$(mktemp)
+{
+    sed -n '/^run_install_cmd()/,/^}/p' "$INSTALL_SH"
+    sed -n '/^run_install_cmd_retry()/,/^}/p' "$INSTALL_SH"
+    sed -n '/^tauri_log()/,/^}/p' "$INSTALL_SH"
+    sed -n '/^tauri_stream_log()/,/^}/p' "$INSTALL_SH"
+    sed -n '/^tauri_clear_install_error()/,/^}/p' "$INSTALL_SH"
+} > "$_FUNC_FILE"
+# shellcheck disable=SC1090
+. "$_FUNC_FILE"
+rm -f "$_FUNC_FILE"
+
+substep() {
+    :
+}
+
+step() {
+    :
+}
+
+sleep() {
+    :
+}
+
+_is_verbose() {
+    return 1
+}
+
+_redact_install_output() {
+    cat "$@"
+}
+
+echo "=== run_install_cmd_retry Tauri failure context ==="
+
+TAURI_MODE=true
+_test_attempt=0
+_test_command() {
+    _test_attempt=$((_test_attempt + 1))
+    [ "$_test_attempt" -eq 2 ]
+}
+
+UNSLOTH_INSTALL_RETRIES=3
+UNSLOTH_INSTALL_RETRY_DELAY=0
+_stdout_file=$(mktemp)
+_stderr_file=$(mktemp)
+trap 'rm -f "$_stdout_file" "$_stderr_file"' EXIT
+run_install_cmd_retry "install PyTorch" _test_command >"$_stdout_file" 2>"$_stderr_file"
+_stdout_clear_count=$(grep -c '^\[TAURI:ERROR_CLEAR\] install PyTorch recovered$' "$_stdout_file")
+_stderr_clear_count=$(grep -c '^\[TAURI:ERROR_CLEAR\] install PyTorch recovered$' "$_stderr_file")
+if [ "$_stdout_clear_count" -ne 1 ] || [ "$_stderr_clear_count" -ne 1 ]; then
+    echo "  FAIL: recovered retry emitted $_stdout_clear_count stdout and $_stderr_clear_count stderr clear markers"
+    exit 1
+fi
+echo "  PASS: recovered retry clears stale context on both streams"
+
+_test_command() {
+    printf '%s\n' "resolver error: no space left on device"
+    return 9
+}
+
+if run_install_cmd_retry "install PyTorch" _test_command >"$_stdout_file" 2>"$_stderr_file"; then
+    echo "  FAIL: permanent failure returned success"
+    exit 1
+else
+    _exit_code=$?
+fi
+if [ "$_exit_code" -ne 9 ]; then
+    echo "  FAIL: permanent failure returned exit code $_exit_code"
+    exit 1
+fi
+if grep -q '^\[TAURI:ERROR_CLEAR\]' "$_stdout_file" ||
+    grep -q '^\[TAURI:ERROR_CLEAR\]' "$_stderr_file"; then
+    echo "  FAIL: permanent failure cleared its failure context"
+    exit 1
+fi
+if ! grep -qxF '[TAURI:OUTPUT_CLEAR] install PyTorch' "$_stderr_file" ||
+    ! grep -qxF 'resolver error: no space left on device' "$_stderr_file" ||
+    ! tail -n 1 "$_stderr_file" |
+        grep -qxF '[TAURI:ERROR_OUTPUT] install PyTorch failed (exit code 9)'; then
+    echo "  FAIL: quiet failure did not bind its command output to the structured error"
+    exit 1
+fi
+echo "  PASS: permanent failure retains its command output and exit code"
+
+UNSLOTH_INSTALL_RETRIES=1
+if run_install_cmd_retry "preferred PyTorch build" _test_command >"$_stdout_file" 2>"$_stderr_file"; then
+    echo "  FAIL: failed preferred build returned success"
+    exit 1
+fi
+_test_command() {
+    return 0
+}
+run_install_cmd_retry "fallback PyTorch build" _test_command >"$_stdout_file" 2>"$_stderr_file"
+if ! grep -q '^\[TAURI:ERROR_CLEAR\] fallback PyTorch build recovered$' "$_stdout_file" ||
+    ! grep -q '^\[TAURI:ERROR_CLEAR\] fallback PyTorch build recovered$' "$_stderr_file"; then
+    echo "  FAIL: successful fallback retained the preferred build failure"
+    exit 1
+fi
+echo "  PASS: successful fallback clears an exhausted preferred failure"
+
+_test_command() {
+    return 0
+}
+run_install_cmd "successful unstructured fallback" _test_command >"$_stdout_file" 2>"$_stderr_file"
+if ! grep -q '^\[TAURI:ERROR_CLEAR\] successful unstructured fallback recovered$' "$_stdout_file" ||
+    ! grep -q '^\[TAURI:ERROR_CLEAR\] successful unstructured fallback recovered$' "$_stderr_file"; then
+    echo "  FAIL: initial success did not clear unstructured failure context"
+    exit 1
+fi
+echo "  PASS: every successful wrapped command clears unstructured failure context"
+
+_is_verbose() {
+    return 0
+}
+_test_command() {
+    printf '%s\n' "resolver error: proxy authentication required"
+    return 7
+}
+set +e
+(
+    set -e
+    run_install_cmd "verbose failure" _test_command
+) >"$_stdout_file" 2>"$_stderr_file"
+_exit_code=$?
+set -e
+if [ "$_exit_code" -ne 7 ]; then
+    echo "  FAIL: verbose failure returned exit code $_exit_code instead of 7"
+    exit 1
+fi
+if ! grep -qxF '[TAURI:OUTPUT_CLEAR] verbose failure' "$_stdout_file" ||
+    ! grep -qxF 'resolver error: proxy authentication required' "$_stdout_file" ||
+    ! tail -n 1 "$_stdout_file" |
+        grep -qxF '[TAURI:ERROR_OUTPUT] verbose failure failed (exit code 7)'; then
+    echo "  FAIL: verbose failure did not bind its command output and exit code"
+    exit 1
+fi
+echo "  PASS: verbose failure retains its command output and exit code under set -e"
+
+_test_command() {
+    _cmd_rc=9
+    return 0
+}
+run_install_cmd "verbose clobbering success" _test_command >"$_stdout_file" 2>"$_stderr_file"
+if ! grep -q '^\[TAURI:ERROR_CLEAR\] verbose clobbering success recovered$' "$_stdout_file"; then
+    echo "  FAIL: verbose success inherited a status variable written by the wrapped function"
+    exit 1
+fi
+echo "  PASS: verbose success records its status after the wrapped function returns"
+
+_test_command() {
+    return 7
+}
+_missing_status_parent=$(mktemp -d)
+rmdir "$_missing_status_parent"
+_missing_status_path="$_missing_status_parent/status"
+set +e
+(
+    set -e
+    mktemp() {
+        printf '%s\n' "$_missing_status_path"
+    }
+    run_install_cmd "missing status file" _test_command
+) >"$_stdout_file" 2>"$_stderr_file"
+_exit_code=$?
+set -e
+if [ "$_exit_code" -ne 1 ] ||
+    ! grep -q '^\[TAURI:ERROR_OUTPUT\] missing status file failed (exit code 1)$' "$_stdout_file"; then
+    echo "  FAIL: missing verbose status defaulted to an empty or invalid exit code"
+    exit 1
+fi
+echo "  PASS: missing verbose status defaults before reporting the failure"
+
+_SETUP_FUNC_FILE=$(mktemp)
+sed -n '/^setup_fail()/,/^}/p' "$SETUP_SH" > "$_SETUP_FUNC_FILE"
+# shellcheck disable=SC1090
+. "$_SETUP_FUNC_FILE"
+rm -f "$_SETUP_FUNC_FILE"
+
+set +e
+(
+    UNSLOTH_TAURI_MODE=1
+    setup_fail 7 "specific setup failure"
+) >"$_stdout_file" 2>"$_stderr_file"
+_exit_code=$?
+set -e
+if [ "$_exit_code" -ne 7 ] ||
+    ! grep -qxF '[TAURI:ERROR] specific setup failure' "$_stdout_file"; then
+    echo "  FAIL: Tauri setup failure did not emit its explicit error and exit code"
+    exit 1
+fi
+
+set +e
+(
+    UNSLOTH_TAURI_MODE=0
+    setup_fail 7 "specific setup failure"
+) >"$_stdout_file" 2>"$_stderr_file"
+_exit_code=$?
+set -e
+if [ "$_exit_code" -ne 7 ] || [ -s "$_stdout_file" ] || [ -s "$_stderr_file" ]; then
+    echo "  FAIL: non-Tauri setup failure emitted desktop protocol output"
+    exit 1
+fi
+echo "  PASS: setup failures emit explicit context only in Tauri mode"
+
+_setup_mode_count=$(grep -c 'UNSLOTH_TAURI_MODE="$TAURI_MODE"' "$INSTALL_SH")
+if [ "$_setup_mode_count" -ne 2 ]; then
+    echo "  FAIL: Unix installer does not pass Tauri mode to both setup invocations"
+    exit 1
+fi
+
+_setup_exit_count=$(grep -Ec '^[[:space:]]*exit[[:space:]]+' "$SETUP_SH")
+if [ "$_setup_exit_count" -ne 1 ] ||
+    ! grep -q '^[[:space:]]*exit "\$exit_code"$' "$SETUP_SH"; then
+    echo "  FAIL: Unix setup has explicit exits outside setup_fail"
+    exit 1
+fi
+echo "  PASS: Unix setup routes explicit exits through setup_fail"
+
+_rollback_block=$(sed -n \
+    '/^_restore_studio_venv_replacement()/,/^}/p' \
+    "$INSTALL_SH")
+_rollback_progress_count=$(printf '%s\n' "$_rollback_block" |
+    grep -c 'rollback_substep')
+if [ "$_rollback_progress_count" -ne 2 ]; then
+    echo "  FAIL: successful Unix rollback output can replace failure context"
+    exit 1
+fi
+echo "  PASS: successful Unix rollback remains structured progress"
+
+_setup_success_block=$(sed -n \
+    '/^if \[ "$_SETUP_EXIT" -eq 0 \]; then$/,/^mkdir -p "\$_LOCAL_BIN"$/p' \
+    "$INSTALL_SH")
+if ! printf '%s\n' "$_setup_success_block" |
+    grep -q 'tauri_clear_install_error "studio setup completed"'; then
+    echo "  FAIL: successful studio setup does not clear recovered setup errors before post-setup work"
+    exit 1
+fi
+
+_setup_failure_block=$(sed -n \
+    '/^# If setup.sh failed, report and exit now\.$/,/^fi$/p' \
+    "$INSTALL_SH")
+if ! printf '%s\n' "$_setup_failure_block" |
+    grep -q 'tauri_log "ERROR_DEFAULT" "studio setup failed'; then
+    echo "  FAIL: failed studio setup does not preserve output before its generic fallback"
+    exit 1
+fi
+echo "  PASS: studio setup success clears recovered errors and failure preserves specific output"
+
+_ps_setup_block=$(sed -n \
+    '/if (\$setupExit -ne 0) {/,/# ── Expose `unsloth` via a shim dir/p' \
+    "$INSTALL_PS1")
+if ! printf '%s\n' "$_ps_setup_block" | grep -q 'Exit-InstallFailure' ||
+    ! printf '%s\n' "$_ps_setup_block" |
+        grep -q 'Clear-TauriInstallError "studio setup completed"'; then
+    echo "  FAIL: Windows setup does not preserve failed output and clear successful output"
+    exit 1
+fi
+echo "  PASS: Windows setup uses the same failure-context boundaries"
+
+if ! grep -q '\$env:UNSLOTH_TAURI_MODE = if (\$TauriMode)' "$INSTALL_PS1"; then
+    echo "  FAIL: Windows installer does not pass Tauri mode to setup"
+    exit 1
+fi
+
+_ps_setup_exit_count=$(grep -Ec '^[[:space:]]*exit[[:space:]]+' "$SETUP_PS1")
+if [ "$_ps_setup_exit_count" -ne 1 ] ||
+    ! grep -q '^[[:space:]]*exit \$Code$' "$SETUP_PS1"; then
+    echo "  FAIL: Windows setup has explicit exits outside Exit-SetupFailure"
+    exit 1
+fi
+echo "  PASS: Windows setup routes explicit exits through Exit-SetupFailure"
+
+_ps_command_block=$(sed -n \
+    '/function Invoke-InstallCommand {/,/function New-StudioShortcuts {/p' \
+    "$INSTALL_PS1")
+if ! printf '%s\n' "$_ps_command_block" |
+    grep -q 'Write-TauriLog "ERROR_OUTPUT" "$Label failed' ||
+    ! printf '%s\n' "$_ps_command_block" |
+        grep -q 'Write-TauriLog "OUTPUT_CLEAR" \$Label' ||
+    ! printf '%s\n' "$_ps_command_block" |
+        grep -q 'Clear-TauriInstallError "$Label recovered"' ||
+    ! printf '%s\n' "$_ps_command_block" |
+        grep -q 'Invoke-InstallCommand -Command \$Command -Label \$Label'; then
+    echo "  FAIL: Windows command output is not attributed and cleared at the command boundary"
+    exit 1
+fi
+
+_ps_exit_block=$(sed -n \
+    '/function Exit-InstallFailure {/,/# ── Parse flags/p' \
+    "$INSTALL_PS1")
+if ! printf '%s\n' "$_ps_exit_block" |
+    grep -q 'Write-TauriLog "ERROR_DEFAULT" \$Message'; then
+    echo "  FAIL: Windows finalization can overwrite producer-owned failure context"
+    exit 1
+fi
+echo "  PASS: Windows command failures preserve output through retries and finalization"
diff --git a/tests/sh/test_with_llama_cpp_dir_link_behavior.sh b/tests/sh/test_with_llama_cpp_dir_link_behavior.sh
index fb09e56c51..2d87b7f541 100644
--- a/tests/sh/test_with_llama_cpp_dir_link_behavior.sh
+++ b/tests/sh/test_with_llama_cpp_dir_link_behavior.sh
@@ -37,6 +37,7 @@ case "$block" in *'_has_local_llama_server'*) : ;;
 PREAMBLE='
 set -u
 step() { :; }; substep() { :; }; verbose_substep() { :; }
+setup_fail() { exit "$1"; }
 _assert_studio_owned_or_absent() { :; }
 C_ERR=""
 _STUDIO_HOME_IS_CUSTOM=false