diff --git a/adapters/plugins.tsv b/adapters/plugins.tsv
index 1449ee5..c071183 100644
--- a/adapters/plugins.tsv
+++ b/adapters/plugins.tsv
@@ -4,6 +4,6 @@ i-have-adhd	ayghri/i-have-adhd	i-have-adhd@i-have-adhd	ayghri/i-have-adhd	i-have
 Superpowers	-	superpowers@claude-plugins-official	openai-curated-remote	superpowers@openai-curated-remote	plugin	-	-
 Context7	upstash/context7	context7@context7-marketplace	upstash/context7	context7@context7-marketplace	plugin	-	-
 Caveman	JuliusBrussee/caveman	caveman@caveman	thinkhome-org/caveman-codex	caveman@thinkhome-caveman	plugin	-	-
-Humanizer	blader/humanizer	humanizer@humanizer	-	-	skill	blader/humanizer	-
-Impeccable	pbakaus/impeccable	impeccable@impeccable	-	-	impeccable	-	-
+Humanizer	blader/humanizer	humanizer@humanizer	-	-	skill	blader/humanizer	humanizer
+Impeccable	pbakaus/impeccable	impeccable@skill	pbakaus/impeccable	impeccable	skill	pbakaus/impeccable	impeccable
 Anthropic Frontend Design	anthropics/claude-plugins-official	frontend-design@claude-plugins-official	-	-	skill	anthropics/skills	frontend-design
diff --git a/scripts/lib/managed-extensions.py b/scripts/lib/managed-extensions.py
new file mode 100644
index 0000000..10f0c21
--- /dev/null
+++ b/scripts/lib/managed-extensions.py
@@ -0,0 +1,399 @@
+import argparse
+import csv
+import hashlib
+import io
+import json
+import os
+from pathlib import Path, PurePosixPath
+import re
+import shutil
+import stat
+import subprocess
+import sys
+import tempfile
+import urllib.request
+import zipfile
+
+
+def linked(path):
+    try:
+        metadata = path.lstat()
+    except FileNotFoundError:
+        return False
+    return stat.S_ISLNK(metadata.st_mode) or bool(getattr(metadata, 'st_file_attributes', 0) & 0x400)
+
+
+def safe_path(home, relative):
+    parts = PurePosixPath(relative).parts
+    if not parts or PurePosixPath(relative).is_absolute() or any(p in ('.', '..') or ':' in p or '\\' in p for p in parts):
+        raise ValueError('Invalid managed extension path.')
+    target = home.joinpath(*parts)
+    for item in (target, *target.parents):
+        if item == home:
+            break
+        if linked(item):
+            raise ValueError('Managed extension path contains a link.')
+    return target
+
+
+def digest(path):
+    return hashlib.sha256(path.read_bytes()).hexdigest()
+
+
+def atomic_write(path, data):
+    path.parent.mkdir(parents=True, exist_ok=True)
+    temporary = None
+    try:
+        with tempfile.NamedTemporaryFile(dir=path.parent, delete=False) as stream:
+            temporary = Path(stream.name)
+            stream.write(data)
+            stream.flush()
+            os.fsync(stream.fileno())
+        os.replace(temporary, path)
+    finally:
+        if temporary is not None:
+            temporary.unlink(missing_ok=True)
+
+
+def run_command(arguments, summary=False, home=None):
+    executable = shutil.which(arguments[0])
+    if executable is None:
+        raise ValueError(f'{arguments[0]} CLI is required to manage plugins.')
+    environment = os.environ.copy()
+    if home is not None:
+        environment.update(HOME=str(home), USERPROFILE=str(home), CODEX_HOME=str(home / '.codex'), CLAUDE_CONFIG_DIR=str(home / '.claude'))
+    result = subprocess.run([executable, *arguments[1:]], stdin=subprocess.DEVNULL,
+                            stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True, timeout=180, env=environment)
+    if result.returncode:
+        raise ValueError(f'Extension command failed: {arguments[0]} {" ".join(arguments[1:])}\n{result.stdout}{result.stderr}')
+    if result.stderr:
+        print(result.stderr.rstrip(), file=sys.stderr)
+    if not summary and result.stdout:
+        print(result.stdout.rstrip())
+    elif summary:
+        for line in result.stdout.splitlines():
+            if re.search(r'warn|error|fail|deprecat', line, re.I):
+                print(line)
+    return result.stdout
+
+
+def installed_plugins(client, home=None):
+    result = json.loads(run_command([client, 'plugin', 'list', '--json'], True, home))
+    if client == 'codex':
+        if not isinstance(result, dict) or not isinstance(result.get('installed'), list):
+            raise ValueError('Invalid Codex installed plugin response.')
+        result = result['installed']
+    if not isinstance(result, list):
+        raise ValueError('Invalid installed plugin response.')
+    key = 'id' if client == 'claude' else 'pluginId'
+    if any(not isinstance(item, dict) or not isinstance(item.get(key), str) for item in result):
+        raise ValueError('Invalid installed plugin record.')
+    return {item[key]: item for item in result}
+
+
+def fetch_skill(entry):
+    source = entry['codex_source']
+    if not re.fullmatch(r'[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+', source):
+        raise ValueError('Skill source must be a GitHub owner/repository.')
+    skill = entry['codex_skill']
+    if not re.fullmatch(r'[A-Za-z0-9_-]+', skill):
+        raise ValueError('Skill name is invalid.')
+    request = urllib.request.Request(f'https://codeload.github.com/{source}/zip/HEAD', headers={'User-Agent': 'MyAiConfiguration'})
+    with urllib.request.urlopen(request, timeout=60) as response:
+        if not response.url.startswith('https://codeload.github.com/'):
+            raise ValueError('Unexpected skill download redirect.')
+        payload = response.read(32 * 1024 * 1024 + 1)
+    if len(payload) > 32 * 1024 * 1024:
+        raise ValueError('Skill archive exceeds the download limit.')
+    with zipfile.ZipFile(io.BytesIO(payload)) as archive:
+        members = archive.infolist()
+        roots = {item.filename.split('/')[0] for item in members}
+        if len(roots) != 1:
+            raise ValueError('Skill archive has an invalid root.')
+        root = next(iter(roots)) + '/'
+        prefixes = [root + '.agents/skills/' + skill + '/', root + 'skills/' + skill + '/', root]
+        prefix = next((p for p in prefixes if p + 'SKILL.md' in archive.namelist()), None)
+        if prefix is None:
+            raise ValueError(f'Skill payload is missing: {skill}')
+        files = {}
+        total = 0
+        for item in members:
+            if not item.filename.startswith(prefix) or item.is_dir():
+                continue
+            relative = item.filename[len(prefix):]
+            if prefix == root and relative != 'SKILL.md' and not relative.startswith(('references/', 'scripts/', 'assets/', 'agents/')):
+                continue
+            if stat.S_ISLNK(item.external_attr >> 16):
+                raise ValueError('Skill archive contains a symbolic link.')
+            parts = PurePosixPath(relative).parts
+            if not parts or any(p in ('.', '..') or ':' in p or '\\' in p for p in parts) or relative.startswith('/'):
+                raise ValueError('Skill archive contains an unsafe path.')
+            total += item.file_size
+            if total > 64 * 1024 * 1024 or len(files) >= 10000:
+                raise ValueError('Skill payload exceeds extraction limits.')
+            if relative in files:
+                raise ValueError('Skill archive contains duplicate paths.')
+            files[relative] = (archive.read(item), bool(item.external_attr >> 16 & 0o111))
+    return skill, files
+
+
+class Manager:
+    def __init__(self, home, dry_run=False, update=False, summary=False):
+        self.home = Path(home).absolute()
+        self.path = safe_path(self.home, '.my-ai-configuration/extensions.json')
+        self.dry_run = dry_run
+        self.update = update
+        self.summary = summary
+        self.state = {'version': 1, 'resources': []}
+        if self.path.exists():
+            self.state = json.loads(self.path.read_text(encoding='utf-8'))
+        self.validate()
+        self.cache = {}
+
+    def validate(self):
+        if not isinstance(self.state, dict) or self.state.get('version') != 1 or not isinstance(self.state.get('resources'), list):
+            raise ValueError('Invalid extension ownership ledger.')
+        identities = set()
+        for resource in self.state['resources']:
+            if not isinstance(resource, dict) or resource.get('client') not in ('codex', 'claude') or resource.get('kind') not in ('plugin', 'skill'):
+                raise ValueError('Invalid extension ownership record.')
+            if not isinstance(resource.get('name'), str) or not resource['name']:
+                raise ValueError('Invalid extension ownership name.')
+            identity = (resource['client'], resource['name'])
+            if identity in identities:
+                raise ValueError('Duplicate extension ownership record.')
+            identities.add(identity)
+            if resource['kind'] == 'plugin':
+                if not re.fullmatch(r'[A-Za-z0-9_.-]+@[A-Za-z0-9_.-]+', resource.get('selector', '')):
+                    raise ValueError('Invalid owned plugin selector.')
+            else:
+                directory = resource.get('directory', '')
+                if not re.fullmatch(r'\.agents/skills/[A-Za-z0-9_-]+', directory) or resource['client'] != 'codex':
+                    raise ValueError('Invalid owned skill directory.')
+                safe_path(self.home, directory)
+                if not isinstance(resource.get('files'), dict):
+                    raise ValueError('Invalid owned skill file inventory.')
+                for relative, value in resource['files'].items():
+                    if not relative.startswith(directory + '/') or not re.fullmatch(r'[a-f0-9]{64}', value):
+                        raise ValueError('Invalid owned skill file record.')
+                    safe_path(self.home, relative)
+
+    def save(self):
+        if not self.dry_run:
+            self.validate()
+            atomic_write(self.path, (json.dumps(self.state, indent=2) + '\n').encode())
+
+    def installed(self, client):
+        if client not in self.cache:
+            self.cache[client] = installed_plugins(client, self.home)
+        return self.cache[client]
+
+    def command(self, arguments):
+        if self.dry_run:
+            if not self.summary:
+                print('DRYRUN ' + ' '.join(arguments))
+        else:
+            run_command(arguments, self.summary, self.home)
+
+    def remove(self, record):
+        if self.dry_run:
+            if not self.summary:
+                print(f'DRYRUN remove managed {record["client"]} {record["name"]}')
+            return
+        if record['kind'] == 'plugin':
+            client, selector = record['client'], record['selector']
+            item = self.installed(client).get(selector)
+            if item is not None:
+                if client == 'claude' and item.get('scope', 'user') != 'user':
+                    raise ValueError('Owned plugin now has a different scope; removal stopped.')
+                arguments = [client, 'plugin', 'uninstall', selector, '--scope', 'user'] if client == 'claude' else [client, 'plugin', 'remove', selector]
+                self.command(arguments)
+                self.cache[client].pop(selector, None)
+        else:
+            empty_candidates = set()
+            for relative, expected in list(record['files'].items()):
+                path = safe_path(self.home, relative)
+                if path.exists():
+                    if not path.is_file() or digest(path) != expected:
+                        print(f'WARN Preserving modified skill file: {relative}')
+                        continue
+                    path.unlink()
+                parent = path.parent
+                directory = safe_path(self.home, record['directory'])
+                while parent != directory.parent:
+                    empty_candidates.add(parent)
+                    parent = parent.parent
+                del record['files'][relative]
+                self.save()
+            directory = safe_path(self.home, record['directory'])
+            if directory.exists():
+                for path in sorted(empty_candidates, key=lambda p: len(p.parts), reverse=True):
+                    if path.is_dir() and not path.is_symlink():
+                        try:
+                            path.rmdir()
+                        except OSError:
+                            pass
+                try:
+                    directory.rmdir()
+                except OSError:
+                    pass
+            if record['files']:
+                return
+        self.state['resources'].remove(record)
+        self.save()
+
+    def ensure(self, client, entry):
+        skill = client == 'codex' and entry['codex_method'] != 'plugin'
+        kind = 'skill' if skill else 'plugin'
+        record = next((r for r in self.state['resources'] if r['client'] == client and r['name'] == entry['name']), None)
+        selector = entry[client + '_plugin']
+        if record and (record['kind'] != kind or (kind == 'plugin' and record['selector'] != selector)):
+            self.remove(record)
+            if not self.dry_run and record in self.state['resources']:
+                raise ValueError('Modified owned files prevent extension replacement.')
+            record = None
+        if self.dry_run:
+            if not self.summary:
+                print(f'DRYRUN ensure {client} {kind}: {entry["name"]}')
+            return
+        if skill:
+            self.ensure_skill(entry, record)
+            return
+        if not re.fullmatch(r'[A-Za-z0-9_.-]+@[A-Za-z0-9_.-]+', selector):
+            raise ValueError('Invalid plugin selector.')
+        item = self.installed(client).get(selector)
+        if item is not None and record is None:
+            if not self.summary:
+                print(f'PASS Preserving pre-existing {client} plugin: {selector}')
+            return
+        if item is not None and client == 'claude' and item.get('scope', 'user') != 'user':
+            raise ValueError('Owned plugin now has a different scope; update stopped.')
+        if item is not None and not self.update:
+            if client == 'claude' and item.get('enabled') is False:
+                self.command([client, 'plugin', 'enable', selector])
+            return
+        if item is not None and client == 'claude':
+            self.command([client, 'plugin', 'update', selector])
+            if item.get('enabled') is False:
+                self.command([client, 'plugin', 'enable', selector])
+            return
+        marketplace = entry[client + '_marketplace']
+        if marketplace not in ('', '-', 'openai-curated-remote'):
+            if not re.fullmatch(r'[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+', marketplace):
+                raise ValueError('Invalid plugin marketplace source.')
+            if item is not None and self.update and client == 'codex':
+                self.command([client, 'plugin', 'marketplace', 'upgrade', selector.rsplit('@', 1)[1]])
+            else:
+                self.command([client, 'plugin', 'marketplace', 'add', marketplace])
+        arguments = [client, 'plugin', 'install', selector, '--scope', 'user'] if client == 'claude' else [client, 'plugin', 'add', selector]
+        self.command(arguments)
+        if record is None:
+            self.state['resources'].append(dict(client=client, name=entry['name'], kind='plugin', selector=selector))
+            self.save()
+        self.cache[client][selector] = {'scope': 'user'}
+
+    def ensure_skill(self, entry, record):
+        skill = entry['codex_skill']
+        if not re.fullmatch(r'[A-Za-z0-9_-]+', skill):
+            raise ValueError('Invalid skill name.')
+        directory = '.agents/skills/' + skill
+        target = self.home / directory
+        alternate = self.home / '.codex' / 'skills' / skill
+        if record is None and (target.exists() or target.is_symlink() or alternate.exists() or alternate.is_symlink()):
+            if not self.summary:
+                print(f'PASS Preserving pre-existing Codex skill: {skill}')
+            return
+        target = safe_path(self.home, directory)
+        if record and record['directory'] != directory:
+            self.remove(record)
+            if record in self.state['resources']:
+                raise ValueError('Modified owned files prevent skill replacement.')
+            record = None
+        if record and record.get('complete') and not self.update and all(safe_path(self.home, name).is_file() for name in record['files']) and record['files']:
+            return
+        _, files = fetch_skill(entry)
+        if record is None:
+            record = dict(client='codex', name=entry['name'], kind='skill', directory=directory, files={}, complete=False)
+            self.state['resources'].append(record)
+            self.save()
+        record['complete'] = False
+        self.save()
+        for name, (content, executable) in files.items():
+            relative = directory + '/' + name
+            path = safe_path(self.home, relative)
+            if path.exists() and (relative not in record['files'] or not path.is_file() or digest(path) != record['files'][relative]):
+                print(f'WARN Preserving modified or foreign skill file: {relative}')
+                continue
+            atomic_write(path, content)
+            if executable:
+                path.chmod(path.stat().st_mode | stat.S_IXUSR)
+            record['files'][relative] = hashlib.sha256(content).hexdigest()
+            self.save()
+        for relative in list(record['files']):
+            if relative[len(directory) + 1:] in files:
+                continue
+            path = safe_path(self.home, relative)
+            if path.exists() and (not path.is_file() or digest(path) != record['files'][relative]):
+                print(f'WARN Preserving modified stale skill file: {relative}')
+                continue
+            path.unlink(missing_ok=True)
+            del record['files'][relative]
+            self.save()
+        record['complete'] = True
+        self.save()
+
+    def sync(self, entries, clients, selected, action='sync'):
+        desired = {entry['name']: entry for entry in entries if entry['name'] in selected}
+        for record in list(self.state['resources']):
+            if record['client'] not in clients:
+                continue
+            if (action == 'sync' and record['name'] not in desired) or (action == 'remove' and record['name'] in selected):
+                self.remove(record)
+        if action != 'remove':
+            for client in clients:
+                for entry in desired.values():
+                    self.ensure(client, entry)
+        print('EXTENSIONS: reconciliation complete' + (' (dry run)' if self.dry_run else ''))
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument('action', choices=('sync', 'install', 'remove'))
+    parser.add_argument('--home', required=True)
+    parser.add_argument('--manifest', required=True)
+    parser.add_argument('--client', choices=('codex', 'claude', 'both'), required=True)
+    parser.add_argument('--selected', nargs='*')
+    parser.add_argument('--dry-run', action='store_true')
+    parser.add_argument('--update', action='store_true')
+    parser.add_argument('--summary', action='store_true')
+    args = parser.parse_args()
+    with open(args.manifest, encoding='utf-8-sig', newline='') as stream:
+        entries = list(csv.DictReader(stream, delimiter='\t'))
+    names = {entry['name'] for entry in entries}
+    if len(names) != len(entries):
+        raise ValueError('Duplicate extension manifest entry.')
+    selected = names if args.selected is None else set(args.selected)
+    if args.action != 'remove' and selected - names:
+        raise ValueError('Unknown selected extension.')
+    clients = ('claude', 'codex') if args.client == 'both' else (args.client,)
+    manager = Manager(args.home, args.dry_run, args.update, args.summary)
+    if args.dry_run:
+        manager.sync(entries, clients, selected, args.action)
+        return
+    lock = safe_path(manager.home, '.my-ai-configuration/extensions.lock')
+    lock.parent.mkdir(parents=True, exist_ok=True)
+    descriptor = os.open(lock, os.O_CREAT | os.O_EXCL | os.O_WRONLY, 0o600)
+    try:
+        os.close(descriptor)
+        manager = Manager(args.home, args.dry_run, args.update, args.summary)
+        manager.sync(entries, clients, selected, args.action)
+    finally:
+        lock.unlink()
+
+
+if __name__ == '__main__':
+    try:
+        main()
+    except (OSError, ValueError, KeyError, subprocess.SubprocessError, zipfile.BadZipFile) as error:
+        print(f'Managed extensions: {error}', file=sys.stderr)
+        sys.exit(1)
diff --git a/scripts/lib/plugins.ps1 b/scripts/lib/plugins.ps1
index d4161c9..531fa3f 100644
--- a/scripts/lib/plugins.ps1
+++ b/scripts/lib/plugins.ps1
@@ -19,7 +19,7 @@ function Invoke-PluginCommand {
         $output = if ($script:PluginNonInteractive) { @($null | & $resolvedCommand @Arguments 2>&1) } else { @(& $resolvedCommand @Arguments 2>&1) }
         $exitCode = $LASTEXITCODE
     } finally { $ErrorActionPreference = $previousPreference }
-    if (-not $Summary -or $env:AI_CONFIG_VERBOSE -eq '1') { $output | Write-Output } elseif ($exitCode -eq 0) { $output | Where-Object { "$_" -match '(?i)warn|error|fail|deprecat' } }
+    if ($exitCode -ne 0 -or -not $Summary -or $env:AI_CONFIG_VERBOSE -eq '1') { $output | Write-Output } else { $output | Where-Object { "$_" -match '(?i)warn|error|fail|deprecat' } }
     if ($exitCode -ne 0) { throw "Plugin command failed: $display" }
 }
 
@@ -35,50 +35,30 @@ function Get-ConfiguredPluginEntries {
 }
 
 function Get-InstalledPlugins {
-    param([ValidateSet('Claude','Codex')][string]$Client)
-    if ($Client -eq 'Claude') {
-        if (-not (Get-Command claude -ErrorAction SilentlyContinue)) { throw 'Claude Code CLI is required to manage Claude plugins.' }
-        $items = (claude plugin list --json | Out-String) | ConvertFrom-Json
-        return @($items)
-    }
-    if (-not (Get-Command codex -ErrorAction SilentlyContinue)) { throw 'Codex CLI is required to manage Codex plugins.' }
-    $items = (codex plugin list --json | Out-String) | ConvertFrom-Json
-    return @($items.installed)
-}
-
-function Ensure-CodexMarketplace {
     param(
-        [Parameter(Mandatory=$true)][string]$Source,
-        [Parameter(Mandatory=$true)][string]$MarketplaceName,
-        [switch]$DryRun,
-        [switch]$Summary
+        [ValidateSet('Claude','Codex')][string]$Client,
+        [string]$HomePath = [Environment]::GetFolderPath('UserProfile')
     )
-    if ($DryRun) {
-        if (-not $Summary) { Write-Output "DRYRUN codex plugin marketplace add $Source" }
-        return
+    $command = Get-Command $Client.ToLowerInvariant() -ErrorAction Stop
+    $environment = @{
+        HOME = $HomePath
+        USERPROFILE = $HomePath
+        CODEX_HOME = (Join-Path $HomePath '.codex')
+        CLAUDE_CONFIG_DIR = (Join-Path $HomePath '.claude')
     }
-    $previousErrorActionPreference = $ErrorActionPreference
+    $previousEnvironment = @{}
+    foreach ($name in $environment.Keys) { $previousEnvironment[$name] = [Environment]::GetEnvironmentVariable($name, 'Process') }
     try {
-        $ErrorActionPreference = 'Continue'
-        $output = if ($script:PluginNonInteractive) { @($null | & codex plugin marketplace add $Source 2>&1) } else { @(& codex plugin marketplace add $Source 2>&1) }
-        $exitCode = $LASTEXITCODE
-    } catch {
-        $output = @($_)
-        $exitCode = 1
+        foreach ($name in $environment.Keys) { [Environment]::SetEnvironmentVariable($name, $environment[$name], 'Process') }
+        $global:LASTEXITCODE = 0
+        $output = $null | & $command plugin list --json | Out-String
+        if ($LASTEXITCODE -ne 0) { throw "$Client plugin listing failed." }
+        $items = $output | ConvertFrom-Json
+        if ($Client -eq 'Claude') { return @($items) }
+        return @($items.installed)
     } finally {
-        $ErrorActionPreference = $previousErrorActionPreference
+        foreach ($name in $previousEnvironment.Keys) { [Environment]::SetEnvironmentVariable($name, $previousEnvironment[$name], 'Process') }
     }
-    if (-not $Summary -or $env:AI_CONFIG_VERBOSE -eq '1') { $output | Write-Output } elseif ($exitCode -eq 0) { $output | Where-Object { "$_" -match '(?i)warn|error|fail|deprecat' } }
-    if ($exitCode -eq 0) { return }
-
-    $text = $output -join [Environment]::NewLine
-    if ($text -match 'marketplace .* already added from a different source') {
-        Write-Output "WARN Codex marketplace '$MarketplaceName' exists from another source; replacing it with: $Source"
-        Invoke-PluginCommand -Command 'codex' -Arguments @('plugin','marketplace','remove',$MarketplaceName) -Summary:$Summary
-        Invoke-PluginCommand -Command 'codex' -Arguments @('plugin','marketplace','add',$Source) -Summary:$Summary
-        return
-    }
-    throw "Plugin command failed: codex plugin marketplace add $Source"
 }
 
 function Read-PluginToggleSelection {
@@ -91,12 +71,6 @@ function Read-PluginToggleSelection {
     $index=0; while($true){ Clear-Host; Write-Host 'Select plugins'; for($i=0;$i -lt $Names.Count;$i++){ $focus=if($i -eq $index){'>'}else{' '}; $mark=if($state[$i]){'x'}else{' '}; Write-Host "$focus [$mark] $($Names[$i])" }; Write-Host 'Up/Down Navigate   Space Toggle   Enter Confirm'; $key=[Console]::ReadKey($true); if($key.Key -eq 'UpArrow'){$index=($index+$Names.Count-1)%$Names.Count}elseif($key.Key -eq 'DownArrow'){$index=($index+1)%$Names.Count}elseif($key.Key -eq 'Spacebar'){$state[$index]= -not $state[$index]}elseif($key.Key -eq 'Enter'){Clear-Host;return $state} }
 }
 
-function Update-CodexMarketplace {
-    param([Parameter(Mandatory=$true)][string]$MarketplaceName,[Parameter(Mandatory=$true)][string]$Source,[switch]$DryRun,[switch]$Summary)
-    try { Invoke-PluginCommand -Command 'codex' -Arguments @('plugin','marketplace','upgrade',$MarketplaceName) -DryRun:$DryRun -Summary:$Summary }
-    catch { Ensure-CodexMarketplace -Source $Source -MarketplaceName $MarketplaceName -DryRun:$DryRun -Summary:$Summary }
-}
-
 function Select-ConfiguredPlugins {
     <#
     .SYNOPSIS
@@ -109,20 +83,23 @@ function Select-ConfiguredPlugins {
         [Parameter(Mandatory=$true)][string]$RepositoryRoot,
         [ValidateSet('Codex','Claude','Both')][Parameter(Mandatory=$true)][string]$Client,
         [ValidateSet('Install','Update')][Parameter(Mandatory=$true)][string]$Mode,
+        [string]$HomePath = [Environment]::GetFolderPath('UserProfile'),
         [switch]$DryRun
     )
     $entries = @(Get-ConfiguredPluginEntries -RepositoryRoot $RepositoryRoot)
-    $toggleable = @($entries | Where-Object { $Client -in @('Claude','Both') -or $_.codex_method -eq 'plugin' })
+    $toggleable = @($entries)
     $fixed = @($entries | Where-Object { $toggleable -notcontains $_ })
     if ($DryRun -or $toggleable.Count -eq 0) { return @{ Selected = $entries; Deselected = @() } }
 
     $referenceClient = if ($Client -eq 'Codex') { 'Codex' } else { 'Claude' }
-    $installed = if ($Mode -eq 'Update') { @(Get-InstalledPlugins -Client $referenceClient) } else { @() }
+    $installed = if ($Mode -eq 'Update') { @(Get-InstalledPlugins -Client $referenceClient -HomePath $HomePath) } else { @() }
     $idField = if ($referenceClient -eq 'Claude') { 'id' } else { 'pluginId' }
     $checked = @($toggleable | ForEach-Object {
         if ($Mode -eq 'Install') { $true; return }
         $selector = if ($referenceClient -eq 'Claude') { $_.claude_plugin } else { $_.codex_plugin }
-        [bool](@($installed | Where-Object { $_.$idField -eq $selector }).Count)
+        if ($referenceClient -eq 'Codex' -and $_.codex_method -ne 'plugin') {
+            (Test-Path -LiteralPath (Join-Path $HomePath ('.agents/skills/' + $_.codex_skill))) -or (Test-Path -LiteralPath (Join-Path $HomePath ('.codex/skills/' + $_.codex_skill)))
+        } else { [bool](@($installed | Where-Object { $_.$idField -eq $selector }).Count) }
     })
     $names = @($toggleable | ForEach-Object { $_.name })
     $checked = Read-PluginToggleSelection -Names $names -Checked $checked
@@ -135,110 +112,62 @@ function Select-ConfiguredPlugins {
     return @{ Selected = ($selected + $fixed); Deselected = $deselected }
 }
 
-function Uninstall-DeselectedPlugins {
+function Invoke-ManagedExtensions {
     param(
-        [Parameter(Mandatory=$true)][AllowEmptyCollection()][object[]]$Entries,
-        [ValidateSet('Codex','Claude','Both')][Parameter(Mandatory=$true)][string]$Client,
+        [Parameter(Mandatory=$true)][string]$RepositoryRoot,
+        [Parameter(Mandatory=$true)][string]$Client,
+        [string]$HomePath = $HOME,
+        [ValidateSet('sync','install','remove')][string]$Action = 'sync',
+        [object[]]$Entries,
         [switch]$DryRun,
+        [switch]$Update,
         [switch]$Summary
     )
-    if ($Entries.Count -eq 0 -and $PSBoundParameters.ContainsKey('Entries')) { return }
-    $clients = if ($Client -eq 'Both') { @('Claude','Codex') } else { @($Client) }
-    foreach ($selectedClient in $clients) {
-        $installed = if ($DryRun) { @() } else { @(Get-InstalledPlugins -Client $selectedClient) }
-        $idField = if ($selectedClient -eq 'Claude') { 'id' } else { 'pluginId' }
-        $removedCount = 0
-        foreach ($entry in $Entries) {
-            $plugin = if ($selectedClient -eq 'Claude') { $entry.claude_plugin } else { $entry.codex_plugin }
-            if ([string]::IsNullOrWhiteSpace($plugin)) { continue }
-            $isInstalled = [bool](@($installed | Where-Object { $_.$idField -eq $plugin }).Count)
-            if (-not $isInstalled) { continue }
-            if ($selectedClient -eq 'Claude') {
-                Invoke-PluginCommand -Command 'claude' -Arguments @('plugin','uninstall',$plugin,'--scope','user') -DryRun:$DryRun -Summary:$Summary
-            } else {
-                Invoke-PluginCommand -Command 'codex' -Arguments @('plugin','remove',$plugin) -DryRun:$DryRun -Summary:$Summary
-            }
-            if (-not $Summary) { Write-Output "PASS $selectedClient plugin removed: $plugin" }
-            $removedCount++
-        }
-        if ($Summary -and $removedCount -gt 0) { Write-Output "PLUGINS ${selectedClient}: $removedCount removed" }
-    }
+    $arguments = @((Join-Path $PSScriptRoot 'managed-extensions.py'), $Action, '--home', $HomePath, '--manifest', (Join-Path $RepositoryRoot 'adapters/plugins.tsv'), '--client', $Client.ToLowerInvariant())
+    if ($DryRun) { $arguments += '--dry-run' }
+    if ($Update) { $arguments += '--update' }
+    if ($Summary) { $arguments += '--summary' }
+    if ($PSBoundParameters.ContainsKey('Entries')) { $arguments += '--selected'; $arguments += @($Entries | ForEach-Object { $_.name }) }
+    & python @arguments
+    if ($LASTEXITCODE -ne 0) { throw 'Managed extension reconciliation failed.' }
+}
+
+function Sync-ConfiguredPlugins {
+    param(
+        [Parameter(Mandatory=$true)][string]$RepositoryRoot,
+        [ValidateSet('Codex','Claude','Both')][Parameter(Mandatory=$true)][string]$Client,
+        [string]$HomePath = $HOME,
+        [object[]]$Entries,
+        [switch]$DryRun,
+        [switch]$Update,
+        [switch]$Summary
+    )
+    Invoke-ManagedExtensions @PSBoundParameters -Action sync
 }
 
 function Install-ConfiguredPlugins {
     param(
         [Parameter(Mandatory=$true)][string]$RepositoryRoot,
         [ValidateSet('Codex','Claude','Both')][Parameter(Mandatory=$true)][string]$Client,
+        [string]$HomePath = $HOME,
+        [object[]]$Entries,
         [switch]$DryRun,
         [switch]$Update,
-        [switch]$Summary,
-        [object[]]$Entries
+        [switch]$Summary
     )
-    $entries = if ($PSBoundParameters.ContainsKey('Entries')) { $Entries } else { @(Get-ConfiguredPluginEntries -RepositoryRoot $RepositoryRoot) }
-    if ($Entries.Count -eq 0 -and $PSBoundParameters.ContainsKey('Entries')) { return }
-    $clients = if ($Client -eq 'Both') { @('Claude','Codex') } else { @($Client) }
-
-    foreach ($selectedClient in $clients) {
-        $installed = if ($DryRun) { @() } else { @(Get-InstalledPlugins -Client $selectedClient) }
-        $tally = @{ Ensured = 0; AlreadyInstalled = 0; Updated = 0 }
-        foreach ($entry in $entries) {
-            $marketplace = if ($selectedClient -eq 'Claude') { $entry.claude_marketplace.Trim() } else { $entry.codex_marketplace.Trim() }
-            if ($marketplace -eq '-') { $marketplace = '' }
-            $plugin = if ($selectedClient -eq 'Claude') { $entry.claude_plugin } else { $entry.codex_plugin }
-            if ([string]::IsNullOrWhiteSpace($plugin)) { throw ('Plugin selector missing for {0}: {1}' -f $selectedClient, $entry.name) }
-
-            if ($selectedClient -eq 'Codex' -and $entry.codex_method -ne 'plugin') {
-                if ($entry.codex_method -eq 'skill') {
-                    $arguments = @('-y','skills','add',$entry.codex_source,'--global','--agent','codex')
-                    if ($entry.codex_skill -ne '-') { $arguments = @('-y','skills','add',$entry.codex_source,'--skill',$entry.codex_skill,'--global','--agent','codex') }
-                } elseif ($entry.codex_method -eq 'impeccable') {
-                    $arguments = @('-y','impeccable','install','-y','--providers=codex','--scope=global')
-                } else {
-                    throw "Unknown Codex install method '$($entry.codex_method)' for $($entry.name)."
-                }
-                Invoke-PluginCommand -Command 'npx' -Arguments $arguments -DryRun:$DryRun -Summary:$Summary
-                if (-not $Summary) { Write-Output "PASS Codex skill ensured: $($entry.name)" }
-                $tally.Ensured++
-                continue
-            }
-
-            $installedItem = if ($selectedClient -eq 'Claude') { $installed | Where-Object { $_.id -eq $plugin } | Select-Object -First 1 } else { $installed | Where-Object { $_.pluginId -eq $plugin } | Select-Object -First 1 }
-            if ($Update -and $selectedClient -eq 'Claude' -and $null -ne $installedItem) {
-                Invoke-PluginCommand -Command 'claude' -Arguments @('plugin','update',$plugin) -DryRun:$DryRun -Summary:$Summary
-                if (-not $installedItem.enabled) {
-                    Invoke-PluginCommand -Command 'claude' -Arguments @('plugin','enable',$plugin) -DryRun:$DryRun -Summary:$Summary
-                }
-                $tally.Updated++
-                continue
-            }
-            if (-not $Update -and $null -ne $installedItem) {
-                if ($selectedClient -eq 'Claude' -and -not $installedItem.enabled) {
-                    Invoke-PluginCommand -Command 'claude' -Arguments @('plugin','enable',$plugin) -DryRun:$DryRun -Summary:$Summary
-                }
-                if (-not $Summary) { Write-Output "PASS $selectedClient plugin already installed: $plugin" }
-                $tally.AlreadyInstalled++
-                continue
-            }
-
-            if ($selectedClient -eq 'Claude') {
-                if (-not [string]::IsNullOrWhiteSpace($marketplace)) {
-                    Invoke-PluginCommand -Command 'claude' -Arguments @('plugin','marketplace','add',$marketplace) -DryRun:$DryRun -Summary:$Summary
-                }
-                Invoke-PluginCommand -Command 'claude' -Arguments @('plugin','install',$plugin,'--scope','user') -DryRun:$DryRun -Summary:$Summary
-            } else {
-                if ($Update -and -not [string]::IsNullOrWhiteSpace($marketplace) -and $marketplace -ne 'openai-curated-remote') {
-                    Update-CodexMarketplace -MarketplaceName (($plugin -split '@')[-1]) -Source $marketplace -DryRun:$DryRun -Summary:$Summary
-                }
-                if (-not [string]::IsNullOrWhiteSpace($marketplace) -and $marketplace -ne 'openai-curated-remote') {
-                    $marketplaceName = ($plugin -split '@')[-1]
-                    Ensure-CodexMarketplace -Source $marketplace -MarketplaceName $marketplaceName -DryRun:$DryRun -Summary:$Summary
-                }
-                Invoke-PluginCommand -Command 'codex' -Arguments @('plugin','add',$plugin) -DryRun:$DryRun -Summary:$Summary
-            }
-            if (-not $Summary) { Write-Output "PASS $selectedClient plugin ensured: $plugin" }
-            if ($Update -and $null -ne $installedItem) { $tally.Updated++ } else { $tally.Ensured++ }
-        }
-        if ($Summary) { Write-Output ("PLUGINS {0}: {1} ensured, {2} already installed, {3} updated" -f $selectedClient, $tally.Ensured, $tally.AlreadyInstalled, $tally.Updated) }
-    }
+    if ($PSBoundParameters.ContainsKey('Entries') -and $Entries.Count -eq 0) { return }
+    Invoke-ManagedExtensions @PSBoundParameters -Action install
 }
 
+function Uninstall-DeselectedPlugins {
+    param(
+        [Parameter(Mandatory=$true)][AllowEmptyCollection()][object[]]$Entries,
+        [ValidateSet('Codex','Claude','Both')][Parameter(Mandatory=$true)][string]$Client,
+        [string]$RepositoryRoot = (Split-Path (Split-Path $PSScriptRoot -Parent) -Parent),
+        [string]$HomePath = $HOME,
+        [switch]$DryRun,
+        [switch]$Summary
+    )
+    if ($Entries.Count -eq 0) { return }
+    Invoke-ManagedExtensions -RepositoryRoot $RepositoryRoot -Client $Client -HomePath $HomePath -Entries $Entries -Action remove -DryRun:$DryRun -Summary:$Summary
+}
diff --git a/scripts/lib/plugins.sh b/scripts/lib/plugins.sh
index 5745a89..6860345 100755
--- a/scripts/lib/plugins.sh
+++ b/scripts/lib/plugins.sh
@@ -22,7 +22,7 @@ run_plugin_command() {
       printf '%s\n' "$output" | grep -Ei 'warn|error|fail|deprecat' || true
     else
       status=$?
-      [ "${AI_CONFIG_VERBOSE:-}" = 1 ] && printf '%s\n' "$output" >&2
+      printf '%s\n' "$output" >&2
       printf 'Plugin command failed: %s\n' "$*" >&2
       return "$status"
     fi
@@ -31,33 +31,6 @@ run_plugin_command() {
   fi
 }
 
-update_codex_marketplace() {
-  local dry_run=$1 marketplace_name=$2 source=$3
-  if ! run_plugin_command "$dry_run" codex plugin marketplace upgrade "$marketplace_name"; then
-    ensure_codex_marketplace "$dry_run" "$source" "$marketplace_name"
-  fi
-}
-
-ensure_codex_marketplace() {
-  local dry_run=$1 source=$2 marketplace_name=$3 output
-  if [ "$dry_run" = true ]; then
-    [ "${summary:-false}" = true ] || printf 'DRYRUN codex plugin marketplace add %s\n' "$source"
-    return 0
-  fi
-  if output=$(codex plugin marketplace add "$source" 2>&1); then
-    [ -z "$output" ] || printf '%s\n' "$output"
-    return 0
-  fi
-  printf '%s\n' "$output" >&2
-  if printf '%s\n' "$output" | grep -Eiq 'marketplace .* already added from a different source'; then
-    printf "WARN Codex marketplace '%s' exists from another source; replacing it with: %s\n" "$marketplace_name" "$source"
-    run_plugin_command false codex plugin marketplace remove "$marketplace_name"
-    run_plugin_command false codex plugin marketplace add "$source"
-    return 0
-  fi
-  return 1
-}
-
 get_plugin_names() {
   local root=$1 name rest
   while IFS=$'\t' read -r name rest; do
@@ -80,9 +53,7 @@ plugin_field() {
 }
 
 plugin_toggleable() {
-  local root=$1 name=$2 client=$3
-  case "$client" in claude|both) return 0;; esac
-  [ "$(plugin_field "$root" "$name" codex_method)" = plugin ]
+  return 0
 }
 
 # read_plugin_toggle_selection <names-array-name> <checked-array-name>
@@ -138,7 +109,11 @@ select_configured_plugins() {
       continue
     fi
     if [ "$reference_client" = claude ]; then selector=$(plugin_field "$root" "$name" claude_plugin); else selector=$(plugin_field "$root" "$name" codex_plugin); fi
-    if plugin_installed "$reference_client" "$selector"; then checked+=(true); else checked+=(false); fi
+    if [ "$reference_client" = codex ] && [ "$(plugin_field "$root" "$name" codex_method)" != plugin ]; then
+      local skill_name
+      skill_name=$(plugin_field "$root" "$name" codex_skill)
+      if [ -d "$HOME/.agents/skills/$skill_name" ] || [ -d "$HOME/.codex/skills/$skill_name" ]; then checked+=(true); else checked+=(false); fi
+    elif plugin_installed "$reference_client" "$selector"; then checked+=(true); else checked+=(false); fi
   done
 
   read_plugin_toggle_selection toggle_names checked
@@ -150,118 +125,35 @@ select_configured_plugins() {
   selected_ref+=("${fixed_names[@]}")
 }
 
-# uninstall_deselected_plugins <root> <client> <dry_run> <deselected-array-name> [summary]
-uninstall_deselected_plugins() {
-  local root=$1 client_selection=$2 dry_run=$3
-  local -n names_ref=$4
-  local summary=${5:-false}
-  local clients=()
-  case "$client_selection" in
-    codex) clients=(codex);;
-    claude) clients=(claude);;
-    both) clients=(claude codex);;
-  esac
-  local client name plugin removed
-  for client in "${clients[@]}"; do
-    removed=0
-    for name in "${names_ref[@]}"; do
-      if [ "$client" = claude ]; then plugin=$(plugin_field "$root" "$name" claude_plugin); else plugin=$(plugin_field "$root" "$name" codex_plugin); fi
-      [ -n "$plugin" ] || continue
-      if [ "$dry_run" = false ] && plugin_installed "$client" "$plugin"; then
-        if [ "$client" = claude ]; then
-          run_plugin_command "$dry_run" claude plugin uninstall "$plugin" --scope user
-        else
-          run_plugin_command "$dry_run" codex plugin remove "$plugin"
-        fi
-        [ "$summary" = true ] || printf 'PASS %s plugin removed: %s\n' "$client" "$plugin"
-        removed=$((removed + 1))
-      fi
-    done
-    if [ "$summary" = true ] && [ "$removed" -gt 0 ]; then printf 'PLUGINS %s: %s removed\n' "$client" "$removed"; fi
-  done
-}
-
-# install_configured_plugins <root> <client> <dry_run> <update> [selected-names-array-name] [summary]
-install_configured_plugins() {
-  local root=$1 client_selection=$2 dry_run=$3 update=$4 selected_name=${5:-} summary=${6:-false}
-  local manifest="$root/adapters/plugins.tsv"
-  [ -f "$manifest" ] || { printf 'Plugin manifest is missing: %s\n' "$manifest" >&2; return 1; }
-
-  local -A selected_set=()
+managed_extensions() {
+  local action=$1 root=$2 client=$3 home_path=$4 dry_run=$5 update=$6 selected_name=${7:-} summary=${8:-false}
+  local arguments=("$root/scripts/lib/managed-extensions.py" "$action" --home "$home_path" --manifest "$root/adapters/plugins.tsv" --client "$client")
+  [ "$dry_run" != true ] || arguments+=(--dry-run)
+  [ "$update" != true ] || arguments+=(--update)
+  [ "$summary" != true ] || arguments+=(--summary)
   if [ -n "$selected_name" ]; then
-    local -n selected_names_ref=$selected_name
-    local sn
-    for sn in "${selected_names_ref[@]}"; do selected_set[$sn]=1; done
+    local -n extension_names_ref=$selected_name
+    arguments+=(--selected "${extension_names_ref[@]}")
   fi
-  local ensured=0 already_installed=0 updated_count=0
+  python3 "${arguments[@]}"
+}
 
-  local clients=()
-  case "$client_selection" in
-    codex) clients=(codex);;
-    claude) clients=(claude);;
-    both) clients=(claude codex);;
-    *) printf 'Unknown plugin client selection: %s\n' "$client_selection" >&2; return 1;;
-  esac
+sync_configured_plugins() {
+  managed_extensions sync "$@"
+}
 
-  local client name claude_marketplace claude_plugin codex_marketplace codex_plugin codex_method codex_source codex_skill marketplace plugin
-  for client in "${clients[@]}"; do
-    ensured=0 already_installed=0 updated_count=0
-    while IFS=$'\t' read -r name claude_marketplace claude_plugin codex_marketplace codex_plugin codex_method codex_source codex_skill; do
-      [ "$name" = name ] && continue
-      [ -n "$name" ] || continue
-      [ -n "$selected_name" ] && [ -z "${selected_set[$name]+x}" ] && continue
-      [ "$claude_marketplace" = - ] && claude_marketplace=
-      [ "$codex_marketplace" = - ] && codex_marketplace=
-      if [ "$client" = claude ]; then marketplace=$claude_marketplace; plugin=$claude_plugin; else marketplace=$codex_marketplace; plugin=$codex_plugin; fi
-      [ -n "$plugin" ] || { printf 'Plugin selector missing for %s: %s\n' "$client" "$name" >&2; return 1; }
-      if [ "$client" = codex ] && [ "$codex_method" != plugin ]; then
-        case "$codex_method" in
-          skill)
-            if [ "$codex_skill" = - ]; then
-              run_plugin_command "$dry_run" npx -y skills add "$codex_source" --global --agent codex
-            else
-              run_plugin_command "$dry_run" npx -y skills add "$codex_source" --skill "$codex_skill" --global --agent codex
-            fi
-            ;;
-          impeccable)
-            run_plugin_command "$dry_run" npx -y impeccable install -y --providers=codex --scope=global
-            ;;
-          *) printf 'Unknown Codex install method for %s: %s\n' "$client" "$name" >&2; return 1;;
-        esac
-        [ "$summary" = true ] || printf 'PASS Codex skill ensured: %s\n' "$name"
-        ensured=$((ensured + 1))
-        continue
-      fi
-      if [ "$dry_run" = false ] && plugin_installed "$client" "$plugin"; then
-        if [ "$update" = true ] && [ "$client" = claude ]; then
-          run_plugin_command "$dry_run" claude plugin update "$plugin"
-          run_plugin_command "$dry_run" claude plugin enable "$plugin"
-          updated_count=$((updated_count + 1))
-        elif [ "$update" = true ] && [ "$client" = codex ]; then
-          [ -z "$marketplace" ] || [ "$marketplace" = openai-curated-remote ] || update_codex_marketplace "$dry_run" "${plugin##*@}" "$marketplace"
-          run_plugin_command "$dry_run" codex plugin add "$plugin"
-          updated_count=$((updated_count + 1))
-        else
-          [ "$summary" = true ] || printf 'PASS %s plugin already installed: %s\n' "$client" "$plugin"
-          already_installed=$((already_installed + 1))
-        fi
-        continue
-      fi
-      if [ "$client" = claude ]; then
-        [ -z "$marketplace" ] || run_plugin_command "$dry_run" claude plugin marketplace add "$marketplace"
-        run_plugin_command "$dry_run" claude plugin install "$plugin" --scope user
-      else
-        if [ -n "$marketplace" ] && [ "$marketplace" != openai-curated-remote ]; then
-          marketplace_name=${plugin##*@}
-          ensure_codex_marketplace "$dry_run" "$marketplace" "$marketplace_name"
-        fi
-        run_plugin_command "$dry_run" codex plugin add "$plugin"
-      fi
-      [ "$summary" = true ] || printf 'PASS %s plugin ensured: %s\n' "$client" "$plugin"
-      ensured=$((ensured + 1))
-    done < "$manifest"
-    if [ "$summary" = true ]; then
-      printf 'PLUGINS %s: %s ensured, %s already installed, %s updated\n' "$client" "$ensured" "$already_installed" "$updated_count"
-    fi
-  done
+install_configured_plugins() {
+  local root=$1 client=$2 dry_run=$3 update=$4 selected_name=${5:-} summary=${6:-false} home_path=${7:-$HOME}
+  if [ -n "$selected_name" ]; then
+    local -n install_names_ref=$selected_name
+    [ "${#install_names_ref[@]}" -gt 0 ] || return 0
+  fi
+  managed_extensions install "$root" "$client" "$home_path" "$dry_run" "$update" "$selected_name" "$summary"
+}
+
+uninstall_deselected_plugins() {
+  local root=$1 client=$2 dry_run=$3 selected_name=$4 summary=${5:-false} home_path=${6:-$HOME}
+  local -n removal_names_ref=$selected_name
+  [ "${#removal_names_ref[@]}" -gt 0 ] || return 0
+  managed_extensions remove "$root" "$client" "$home_path" "$dry_run" false "$selected_name" "$summary"
 }
diff --git a/scripts/test-managed-extensions.py b/scripts/test-managed-extensions.py
new file mode 100644
index 0000000..a74181f
--- /dev/null
+++ b/scripts/test-managed-extensions.py
@@ -0,0 +1,205 @@
+import contextlib
+import importlib.util
+import io
+import json
+import os
+from pathlib import Path
+import tempfile
+import unittest
+from unittest.mock import patch
+
+
+spec = importlib.util.spec_from_file_location('extensions', Path(__file__).parent / 'lib' / 'managed-extensions.py')
+extensions = importlib.util.module_from_spec(spec)
+spec.loader.exec_module(extensions)
+
+
+def plugin(name='Example'):
+    return dict(name=name, codex_method='plugin', codex_plugin=name.lower() + '@test', codex_marketplace='-',
+                claude_plugin=name.lower() + '@test', claude_marketplace='-')
+
+
+def skill():
+    return dict(name='Humanizer', codex_method='skill', codex_source='blader/humanizer', codex_skill='humanizer', codex_plugin='-')
+
+
+class ManagedExtensionTests(unittest.TestCase):
+    def setUp(self):
+        self.temporary = tempfile.TemporaryDirectory()
+        self.addCleanup(self.temporary.cleanup)
+        self.home = Path(self.temporary.name)
+        self.installed = {'codex': {}, 'claude': {}}
+        self.commands = []
+        self.addCleanup(patch.stopall)
+        patch.object(extensions, 'installed_plugins', side_effect=lambda client, home: dict(self.installed[client])).start()
+        patch.object(extensions, 'run_command', side_effect=self.command).start()
+        patch.object(extensions, 'fetch_skill', return_value=('humanizer', {'SKILL.md': (b'original', False), 'references/old.md': (b'old', False)})).start()
+        self.output = contextlib.redirect_stdout(io.StringIO())
+        self.output.__enter__()
+        self.addCleanup(self.output.__exit__, None, None, None)
+
+    def command(self, args, summary, home=None):
+        self.commands.append(args)
+        if args[2] in ('add', 'install') and args[1] == 'plugin':
+            self.installed[args[0]][args[3]] = {'scope': 'user'}
+        if args[2] in ('remove', 'uninstall'):
+            self.installed[args[0]].pop(args[3], None)
+        return ''
+
+    def manager(self, **kwargs):
+        return extensions.Manager(self.home, **kwargs)
+
+    def test_foreign_plugin_is_never_claimed_or_removed(self):
+        self.installed['codex']['example@test'] = {}
+        self.manager(update=True).sync([plugin()], ['codex'], {'Example'})
+        self.manager().sync([], ['codex'], set())
+        self.assertEqual([], self.commands)
+        self.assertEqual([], self.manager().state['resources'])
+
+    def test_owned_plugin_removed_after_manifest_entry_disappears(self):
+        self.manager().sync([plugin()], ['codex'], {'Example'})
+        self.manager().sync([], ['codex'], set())
+        self.assertEqual(['codex', 'plugin', 'remove', 'example@test'], self.commands[-1])
+        self.assertEqual([], self.manager().state['resources'])
+
+    def test_client_scope_is_preserved(self):
+        self.manager().sync([plugin()], ['claude', 'codex'], {'Example'})
+        self.manager().sync([], ['codex'], set())
+        self.assertEqual(['claude'], [r['client'] for r in self.manager().state['resources']])
+
+    def test_partial_plugin_failure_retains_successful_ownership(self):
+        with patch.object(extensions, 'run_command', side_effect=[None, ValueError('failure')]):
+            with self.assertRaises(ValueError):
+                self.manager().sync([plugin(), plugin('Second')], ['codex'], {'Example', 'Second'})
+        self.assertEqual(['Example'], [r['name'] for r in self.manager().state['resources']])
+
+    def test_failed_removal_retains_ownership(self):
+        self.manager().sync([plugin()], ['codex'], {'Example'})
+        with patch.object(extensions, 'run_command', side_effect=ValueError('failure')):
+            with self.assertRaises(ValueError):
+                self.manager().sync([], ['codex'], set())
+        self.assertEqual(1, len(self.manager().state['resources']))
+
+    def test_foreign_skill_directory_is_preserved(self):
+        target = self.home / '.agents/skills/humanizer/SKILL.md'
+        target.parent.mkdir(parents=True)
+        target.write_text('foreign')
+        self.manager(update=True).sync([skill()], ['codex'], {'Humanizer'})
+        self.manager().sync([], ['codex'], set())
+        self.assertEqual('foreign', target.read_text())
+        self.assertEqual([], self.manager().state['resources'])
+
+    def test_skill_removal_preserves_modified_and_foreign_files(self):
+        self.manager().sync([skill()], ['codex'], {'Humanizer'})
+        directory = self.home / '.agents/skills/humanizer'
+        (directory / 'SKILL.md').write_text('modified')
+        (directory / 'foreign.txt').write_text('foreign')
+        self.manager().sync([], ['codex'], set())
+        self.assertEqual('modified', (directory / 'SKILL.md').read_text())
+        self.assertTrue((directory / 'foreign.txt').exists())
+        self.assertFalse((directory / 'references/old.md').exists())
+        self.assertEqual(1, len(self.manager().state['resources'][0]['files']))
+
+    def test_skill_update_cleans_only_owned_stale_files(self):
+        self.manager().sync([skill()], ['codex'], {'Humanizer'})
+        directory = self.home / '.agents/skills/humanizer'
+        (directory / 'foreign.txt').write_text('foreign')
+        with patch.object(extensions, 'fetch_skill', return_value=('humanizer', {'SKILL.md': (b'new', False)})):
+            self.manager(update=True).sync([skill()], ['codex'], {'Humanizer'})
+        self.assertEqual('new', (directory / 'SKILL.md').read_text())
+        self.assertTrue((directory / 'foreign.txt').exists())
+        self.assertFalse((directory / 'references/old.md').exists())
+
+    def test_skill_partial_failure_records_each_successful_file(self):
+        original_write = extensions.atomic_write
+        def write(path, content):
+            if path.name == 'old.md':
+                raise OSError('simulated disk failure')
+            original_write(path, content)
+        with patch.object(extensions, 'atomic_write', side_effect=write):
+            with self.assertRaises(OSError):
+                self.manager().sync([skill()], ['codex'], {'Humanizer'})
+        self.assertEqual(['.agents/skills/humanizer/SKILL.md'], list(self.manager().state['resources'][0]['files']))
+        self.manager().sync([skill()], ['codex'], {'Humanizer'})
+        self.assertEqual(2, len(self.manager().state['resources'][0]['files']))
+        self.assertTrue(self.manager().state['resources'][0]['complete'])
+
+    def test_dry_run_has_no_commands_network_or_writes(self):
+        self.manager(dry_run=True).sync([plugin(), skill()], ['codex'], {'Example', 'Humanizer'})
+        self.assertEqual([], list(self.home.iterdir()))
+        self.assertEqual([], self.commands)
+        extensions.fetch_skill.assert_not_called()
+
+    def test_traversal_ledger_is_rejected(self):
+        path = self.home / '.my-ai-configuration/extensions.json'
+        path.parent.mkdir()
+        path.write_text(json.dumps({'version': 1, 'resources': [dict(client='codex', name='Bad', kind='skill', directory='.agents/skills/bad', files={'.agents/skills/bad/../../../other': '0' * 64})]}))
+        with self.assertRaises(ValueError):
+            self.manager()
+
+    def test_marketplace_failure_never_removes_existing_source(self):
+        entry = plugin()
+        entry['codex_marketplace'] = 'owner/repository'
+        with patch.object(extensions, 'run_command', side_effect=ValueError('different source')) as command:
+            with self.assertRaises(ValueError):
+                self.manager().sync([entry], ['codex'], {'Example'})
+        self.assertEqual(1, command.call_count)
+        self.assertEqual('add', command.call_args.args[0][3])
+
+    def test_owned_codex_update_upgrades_marketplace(self):
+        entry = plugin()
+        entry['codex_marketplace'] = 'owner/repository'
+        self.manager().sync([entry], ['codex'], {'Example'})
+        self.commands.clear()
+        self.manager(update=True).sync([entry], ['codex'], {'Example'})
+        self.assertEqual([['codex', 'plugin', 'marketplace', 'upgrade', 'test'], ['codex', 'plugin', 'add', 'example@test']], self.commands)
+
+    def test_owned_disabled_claude_is_enabled(self):
+        self.manager().sync([plugin()], ['claude'], {'Example'})
+        self.installed['claude']['example@test']['enabled'] = False
+        self.manager(update=True).sync([plugin()], ['claude'], {'Example'})
+        self.assertEqual(['claude', 'plugin', 'enable', 'example@test'], self.commands[-1])
+
+    def test_dry_run_summary_has_one_line(self):
+        with contextlib.redirect_stdout(io.StringIO()) as output:
+            self.manager(dry_run=True, summary=True).sync([plugin(), skill()], ['codex'], {'Example', 'Humanizer'})
+        self.assertEqual('EXTENSIONS: reconciliation complete (dry run)\n', output.getvalue())
+
+    def test_foreign_empty_directory_survives_skill_removal(self):
+        self.manager().sync([skill()], ['codex'], {'Humanizer'})
+        foreign = self.home / '.agents/skills/humanizer/foreign-empty'
+        foreign.mkdir()
+        self.manager().sync([], ['codex'], set())
+        self.assertTrue(foreign.is_dir())
+
+    def test_foreign_skill_link_is_preserved(self):
+        foreign = self.home / 'foreign'
+        foreign.mkdir()
+        target = self.home / '.agents/skills/humanizer'
+        target.parent.mkdir(parents=True)
+        try:
+            target.symlink_to(foreign, target_is_directory=True)
+        except OSError:
+            self.skipTest('Symbolic links are unavailable on this host.')
+        self.manager().sync([skill()], ['codex'], {'Humanizer'})
+        self.assertTrue(target.is_symlink())
+        extensions.fetch_skill.assert_not_called()
+
+
+class CommandTests(unittest.TestCase):
+    def test_subprocess_uses_intended_home_and_cmd_launcher(self):
+        with tempfile.TemporaryDirectory(prefix='managed extensions ') as temporary:
+            home = Path(temporary)
+            executable = home / ('mock.cmd' if os.name == 'nt' else 'mock')
+            if os.name == 'nt':
+                executable.write_text('@echo off\necho %CODEX_HOME%\necho %CLAUDE_CONFIG_DIR%\n')
+            else:
+                executable.write_text('#!/bin/sh\nprintf "%s\\n" "$CODEX_HOME" "$CLAUDE_CONFIG_DIR"\n')
+                executable.chmod(0o700)
+            with contextlib.redirect_stdout(io.StringIO()):
+                result = extensions.run_command([str(executable), 'plugin', 'list', '--json'], True, home)
+            self.assertEqual([str(home / '.codex'), str(home / '.claude')], result.splitlines())
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/scripts/test-plugin-selection.ps1 b/scripts/test-plugin-selection.ps1
index db11214..409c217 100644
--- a/scripts/test-plugin-selection.ps1
+++ b/scripts/test-plugin-selection.ps1
@@ -30,26 +30,32 @@ $detailed = @(Invoke-PluginCommand -Command Test-PluginOutput -Arguments @('succ
 if ($detailed.Count -ne 2 -or $detailed[0] -ne 'download progress') { throw 'Detailed output must retain progress.' }
 $diagnostics = [System.Collections.Generic.List[string]]::new()
 $failed = $false
-$env:AI_CONFIG_VERBOSE = '1'
+$env:AI_CONFIG_VERBOSE = $null
 try { Invoke-PluginCommand -Command Test-PluginOutput -Arguments @('fail') -Summary | ForEach-Object { $diagnostics.Add("$_") } }
 catch { $failed = $true }
 $env:AI_CONFIG_VERBOSE = $null
 if (-not $failed -or $diagnostics -notcontains 'download progress' -or $diagnostics -notcontains 'WARN test warning') { throw 'Plugin failure must retain full diagnostics and fail.' }
 $global:LASTEXITCODE = 0
-function codex { '{"installed":[{"pluginId":"ponytail@ponytail"},{"pluginId":"i-have-adhd@i-have-adhd"},{"pluginId":"superpowers@openai-curated-remote"},{"pluginId":"context7@context7-marketplace"},{"pluginId":"caveman@thinkhome-caveman"}],"available":[]}' }
+function codex { $script:observedCodexHome = $env:CODEX_HOME; $script:observedProfile = $env:USERPROFILE; '{"installed":[{"pluginId":"ponytail@ponytail"},{"pluginId":"i-have-adhd@i-have-adhd"},{"pluginId":"superpowers@openai-curated-remote"},{"pluginId":"context7@context7-marketplace"},{"pluginId":"caveman@thinkhome-caveman"}],"available":[]}' }
+$previousCodexHome = $env:CODEX_HOME
+$previousProfile = $env:USERPROFILE
+$null = Get-InstalledPlugins -Client Codex -HomePath 'C:/temporary profile'
+if ($observedCodexHome -ne (Join-Path 'C:/temporary profile' '.codex') -or $observedProfile -ne 'C:/temporary profile') { throw 'Plugin inspection must use the requested user home.' }
+if ($env:CODEX_HOME -ne $previousCodexHome -or $env:USERPROFILE -ne $previousProfile) { throw 'Plugin inspection must restore the process environment.' }
 $script:answers.Enqueue('done')
 $selection = Select-ConfiguredPlugins -RepositoryRoot (Split-Path $PSScriptRoot -Parent) -Client Codex -Mode Update
-if ($selection.Deselected.Count -ne 0 -or $selection.Selected.Count -ne 8) { throw 'All installed Codex plugins must start checked when updating.' }
+if (@($selection.Selected | Where-Object { $_.codex_method -eq 'plugin' }).Count -ne 5) { throw 'All installed Codex plugins must start checked when updating.' }
 $script:answers.Enqueue('4')
 $script:answers.Enqueue('done')
 $selection = Select-ConfiguredPlugins -RepositoryRoot (Split-Path $PSScriptRoot -Parent) -Client Codex -Mode Update
-if ($selection.Deselected.Count -ne 1 -or $selection.Deselected[0].name -ne 'Context7') { throw 'Only the explicitly unchecked installed plugin must be deselected.' }
-function Get-InstalledPlugins { [pscustomobject]@{ pluginId = 'test@market' } }
-$script:commands = @()
-function Invoke-PluginCommand { param($Command, $Arguments, [switch]$DryRun, [switch]$Summary) $script:commands += "$Command $($Arguments -join ' ')" }
+if (@($selection.Deselected | Where-Object { $_.name -eq 'Context7' }).Count -ne 1) { throw 'Only the explicitly unchecked installed plugin must be deselected.' }
+$script:managedArguments = @()
+function python { $script:managedArguments = @($args); $global:LASTEXITCODE = 0 }
 $entry = [pscustomobject]@{ name = 'Test'; codex_method = 'plugin'; codex_marketplace = '-'; codex_plugin = 'test@market' }
-$updated = @(Install-ConfiguredPlugins -RepositoryRoot (Split-Path $PSScriptRoot -Parent) -Client Codex -Update -Summary -Entries @($entry))
-if ($commands.Count -ne 1 -or $commands[0] -ne 'codex plugin add test@market' -or $updated[0] -ne 'PLUGINS Codex: 0 ensured, 0 already installed, 1 updated') { throw 'Updating an installed Codex plugin must report one update.' }
+Sync-ConfiguredPlugins -RepositoryRoot (Split-Path $PSScriptRoot -Parent) -Client Codex -HomePath 'C:/temporary home' -Update -Summary -Entries @($entry)
+if ($managedArguments -notcontains 'sync' -or $managedArguments -notcontains '--update' -or $managedArguments -notcontains 'Test' -or $managedArguments -notcontains 'C:/temporary home') { throw 'Managed reconciliation must receive selection, home, and update mode.' }
+Sync-ConfiguredPlugins -RepositoryRoot (Split-Path $PSScriptRoot -Parent) -Client Codex -Entries @()
+if ($managedArguments[-1] -ne '--selected') { throw 'Empty selection must reach reconciliation for managed cleanup.' }
 function Get-InstalledPlugins { throw 'Empty selection must not query installed plugins.' }
 function Invoke-PluginCommand { throw 'Empty selection must not run plugin commands.' }
 Install-ConfiguredPlugins -RepositoryRoot (Split-Path $PSScriptRoot -Parent) -Client Both -Entries @()