feat(tenancy): establish cloud isolation foundations

src/langbot/pkg/api/http/context.py

@@ -69,6 +69,7 @@ class ExecutionContext:
     pipeline_uuid: str | None = None
     query_uuid: str | None = None
     trigger_principal: PrincipalContext | None = None
+    entitlement_revision: int = 0
 
     @classmethod
     def from_request(
@@ -89,4 +90,5 @@ class ExecutionContext:
             pipeline_uuid=pipeline_uuid,
             query_uuid=query_uuid,
             trigger_principal=ctx.principal,
+            entitlement_revision=ctx.entitlement_revision,
         )

src/langbot/pkg/api/http/controller/group.py

@@ -12,6 +12,7 @@ from quart.typing import RouteCallable
 from ....utils import constants
 from ....workspace.collaboration import MembershipPermissionError, WorkspaceCollaborationError
 from ....workspace.errors import WorkspaceNotFoundError
+from ....cloud.entitlements import EntitlementUnavailableError
 from ..authz import AuthorizationError, Permission, permissions_for_role, require_permission
 from ..context import PrincipalContext, PrincipalType, RequestContext, WorkspaceContext
 
@@ -244,6 +245,10 @@ class RouterGroup(abc.ABC):
 
         requested_workspace_uuid = quart.request.headers.get('X-Workspace-Id')
         access = await collaboration_service.resolve_account_workspace(account_uuid, requested_workspace_uuid)
+        entitlement_revision = await self._resolve_entitlement_revision(
+            access.execution.instance_uuid,
+            access.workspace.uuid,
+        )
         request_context = RequestContext(
             instance_uuid=access.execution.instance_uuid,
             placement_generation=access.execution.placement_generation,
@@ -260,6 +265,7 @@ class RouterGroup(abc.ABC):
                 permissions=permissions_for_role(access.membership.role),
                 membership_revision=access.membership.projection_revision,
             ),
+            entitlement_revision=entitlement_revision,
         )
         quart.g.request_context = request_context
         quart.g.workspace_membership = access.membership
@@ -272,6 +278,10 @@ class RouterGroup(abc.ABC):
             if inspect.isawaitable(authenticated):
                 identity = await authenticated
                 if identity is not None:
+                    entitlement_revision = await self._resolve_entitlement_revision(
+                        identity.instance_uuid,
+                        identity.workspace_uuid,
+                    )
                     request_context = RequestContext(
                         instance_uuid=identity.instance_uuid,
                         placement_generation=identity.placement_generation,
@@ -287,6 +297,7 @@ class RouterGroup(abc.ABC):
                             role=None,
                             permissions=identity.permissions,
                         ),
+                        entitlement_revision=entitlement_revision,
                     )
                     quart.g.request_context = request_context
                     return request_context
@@ -316,6 +327,18 @@ class RouterGroup(abc.ABC):
         quart.g.request_context = request_context
         return request_context
 
+    async def _resolve_entitlement_revision(self, instance_uuid: str, workspace_uuid: str) -> int:
+        deployment = getattr(self.ap, 'deployment', None)
+        if deployment is None or not getattr(deployment, 'multi_workspace_enabled', False):
+            return 0
+        resolver = getattr(self.ap, 'entitlement_resolver', None)
+        if resolver is None:
+            raise EntitlementUnavailableError('Workspace entitlement resolver is unavailable')
+        if instance_uuid != resolver.instance_uuid:
+            raise EntitlementUnavailableError('Workspace entitlement targets another LangBot instance')
+        snapshot = await resolver.resolve(workspace_uuid)
+        return snapshot.entitlement_revision
+
     @staticmethod
     def _inject_handler_context(
         handler: RouteCallable,
@@ -339,6 +362,8 @@ class RouterGroup(abc.ABC):
             return self.http_status(404, 'resource_not_found', 'Resource not found')
         if isinstance(error, MembershipPermissionError):
             return self.http_status(403, error.code, str(error))
+        if isinstance(error, EntitlementUnavailableError):
+            return self.http_status(403, 'entitlement_unavailable', str(error))
         request_id = self.request_id()
         logger = getattr(self.ap, 'logger', self.quart_app.logger)
         logger.warning(f'Authentication failed request_id={request_id} error_type={type(error).__name__}: {error}')

src/langbot/pkg/api/http/controller/groups/resources/mcp.py

@@ -5,6 +5,7 @@ from urllib.parse import unquote
 
 from ....authz import Permission
 from ....context import RequestContext
+from ......provider.tools.loaders.mcp_policy import MCPStdioDisabledError
 from ... import group
 
 
@@ -31,6 +32,8 @@ class MCPRouterGroup(group.RouterGroup):
             data = await quart.request.json
             try:
                 server_uuid = await self.ap.mcp_service.create_mcp_server(request_context, data)
+            except MCPStdioDisabledError as exc:
+                return self.http_status(403, exc.code, str(exc))
             except ValueError as exc:
                 return self.http_status(400, -1, str(exc))
             return self.success(data={'uuid': server_uuid})
@@ -63,6 +66,8 @@ class MCPRouterGroup(group.RouterGroup):
                 data = await quart.request.json
                 try:
                     await self.ap.mcp_service.update_mcp_server(request_context, server_data['uuid'], data)
+                except MCPStdioDisabledError as exc:
+                    return self.http_status(403, exc.code, str(exc))
                 except ValueError as exc:
                     return self.http_status(400, -1, str(exc))
             else:
@@ -79,11 +84,14 @@ class MCPRouterGroup(group.RouterGroup):
             """测试MCP服务器连接"""
             server_name = unquote(server_name)
             server_data = await quart.request.json
-            task_id = await self.ap.mcp_service.test_mcp_server(
-                request_context,
-                server_name=server_name,
-                server_data=server_data,
-            )
+            try:
+                task_id = await self.ap.mcp_service.test_mcp_server(
+                    request_context,
+                    server_name=server_name,
+                    server_data=server_data,
+                )
+            except MCPStdioDisabledError as exc:
+                return self.http_status(403, exc.code, str(exc))
             return self.success(data={'task_id': task_id})
 
         @self.route(

src/langbot/pkg/api/http/controller/groups/system.py

@@ -8,6 +8,7 @@ from .....utils import constants
 from .....entity.persistence.metadata import WorkspaceMetadata
 from ...authz import Permission
 from ...context import RequestContext
+from .....provider.tools.loaders.mcp_policy import stdio_mcp_enabled
 
 
 @group.group_class('system', '/api/v1/system')
@@ -70,6 +71,9 @@ class SystemRouterGroup(group.RouterGroup):
                     'disable_models_service': self.ap.instance_config.data.get('space', {}).get(
                         'disable_models_service', False
                     ),
+                    # Exposed independently of Box status so the WebUI cannot
+                    # infer stdio permission from sandbox availability.
+                    'mcp_stdio_enabled': stdio_mcp_enabled(self.ap),
                     'limitation': self.ap.instance_config.data.get('system', {}).get('limitation', {}),
                     'outbound_ips': outbound_ips,
                     'wizard_status': wizard_status,

src/langbot/pkg/api/http/service/mcp.py

@@ -11,6 +11,7 @@ from ....core import app, taskmgr
 from ....entity.persistence import mcp as persistence_mcp
 from ....entity.persistence import plugin as persistence_plugin
 from ....provider.tools.loaders.mcp import MCPSessionStatus, RuntimeMCPSession
+from ....provider.tools.loaders.mcp_policy import require_stdio_mcp_enabled
 from ....workspace.errors import WorkspaceNotFoundError
 from ..context import ExecutionContext
 from .secrets import is_url_key, redact_url_secrets, restore_url_secret_placeholders
@@ -207,6 +208,10 @@ class MCPService:
         execution_context = await self._execution_context(context)
         workspace_uuid = execution_context.workspace_uuid
 
+        # This gate is independent of Box availability.  Cloud v2 disables
+        # stdio MCP even though Box Runtime itself remains available.
+        require_stdio_mcp_enabled(self.ap, server_data)
+
         limitation = self.ap.instance_config.data.get('system', {}).get('limitation', {})
         max_extensions = limitation.get('max_extensions', -1)
         if max_extensions >= 0:
@@ -315,6 +320,13 @@ class MCPService:
             if duplicate is not None and duplicate['uuid'] != server_uuid:
                 raise ValueError(f'MCP server already exists: {payload["name"]}')
 
+        effective_server = {**old_server, **payload}
+        # Existing disabled rows remain readable/deletable.  Switching away
+        # from stdio or explicitly disabling one is also allowed, but an
+        # update may never leave a disabled stdio server enabled.
+        if bool(effective_server.get('enable', True)):
+            require_stdio_mcp_enabled(self.ap, effective_server)
+
         result = await self.ap.persistence_mgr.execute_async(
             scope_statement(
                 sqlalchemy.update(persistence_mcp.MCPServer)
@@ -405,7 +417,8 @@ class MCPService:
         ctx = taskmgr.TaskContext.new()
 
         if server_name != '_':
-            await self._require_server(execution_context, server_name)
+            _, persisted_server = await self._require_server(execution_context, server_name)
+            require_stdio_mcp_enabled(self.ap, persisted_server)
             runtime_mcp_session = self.ap.tool_mgr.mcp_tool_loader.get_session(execution_context, server_name)
             if runtime_mcp_session is None:
                 raise WorkspaceNotFoundError('MCP server not found')
@@ -427,6 +440,7 @@ class MCPService:
             payload = dict(server_data)
             payload.pop('workspace_uuid', None)
             payload['workspace_uuid'] = execution_context.workspace_uuid
+            require_stdio_mcp_enabled(self.ap, payload)
             runtime_mcp_session = await self.ap.tool_mgr.mcp_tool_loader.load_mcp_server(
                 execution_context,
                 payload,

src/langbot/pkg/cloud/__init__.py

@@ -0,0 +1,27 @@
+"""Contracts used by the optional closed Cloud control-plane bootstrap."""
+
+from .bootstrap import (
+    CloudBootstrapError,
+    OpenSourceDeployment,
+    VerifiedCloudDeployment,
+    resolve_deployment,
+)
+from .entitlements import (
+    EntitlementProvider,
+    EntitlementResolver,
+    EntitlementSnapshot,
+    EntitlementUnavailableError,
+    OpenSourceEntitlementProvider,
+)
+
+__all__ = [
+    'CloudBootstrapError',
+    'EntitlementProvider',
+    'EntitlementResolver',
+    'EntitlementSnapshot',
+    'EntitlementUnavailableError',
+    'OpenSourceDeployment',
+    'OpenSourceEntitlementProvider',
+    'VerifiedCloudDeployment',
+    'resolve_deployment',
+]

src/langbot/pkg/cloud/bootstrap.py

@@ -0,0 +1,161 @@
+from __future__ import annotations
+
+import dataclasses
+import importlib.metadata
+import inspect
+import time
+from collections.abc import Awaitable, Callable
+from typing import Any, Protocol
+
+from ..workspace.policy import CloudWorkspacePolicy, SingleWorkspacePolicy
+from .entitlements import EntitlementProvider, OpenSourceEntitlementProvider
+
+
+CLOUD_BOOTSTRAP_ENTRY_POINT = 'langbot.cloud_bootstrap'
+REQUIRED_TENANT_ISOLATION_VERSION = 2
+
+
+class CloudBootstrapError(RuntimeError):
+    """Fail-closed Cloud bootstrap validation error."""
+
+
+@dataclasses.dataclass(frozen=True, slots=True)
+class OpenSourceDeployment:
+    """Default deployment selected when no closed bootstrap is installed."""
+
+    mode: str = 'oss'
+    workspace_policy: SingleWorkspacePolicy = dataclasses.field(default_factory=SingleWorkspacePolicy)
+    entitlement_provider: OpenSourceEntitlementProvider = dataclasses.field(
+        default_factory=OpenSourceEntitlementProvider
+    )
+    persistence_mode: str = 'oss_compat'
+    required_vector_backend: str | None = None
+
+    @property
+    def multi_workspace_enabled(self) -> bool:
+        return False
+
+    def validate_instance_config(self, config: dict[str, Any]) -> None:
+        del config
+
+
+@dataclasses.dataclass(frozen=True, slots=True)
+class VerifiedCloudDeployment:
+    """Receipt returned only after the closed package verifies a Manifest.
+
+    Core deliberately does not accept a config flag as a substitute for this
+    object.  The closed entry point owns root-key/JWS verification and the
+    entitlement adapter; open Core validates the receipt's runtime invariants.
+    """
+
+    instance_uuid: str
+    manifest_jti: str
+    manifest_generation: int
+    expires_at: int
+    release: str
+    capabilities: frozenset[str]
+    tenant_isolation_version: int
+    entitlement_provider: EntitlementProvider
+    verification_key_id: str
+    mode: str = dataclasses.field(default='cloud', init=False)
+    workspace_policy: CloudWorkspacePolicy = dataclasses.field(default_factory=CloudWorkspacePolicy, init=False)
+    persistence_mode: str = dataclasses.field(default='cloud_runtime', init=False)
+    required_vector_backend: str = dataclasses.field(default='pgvector', init=False)
+
+    @property
+    def multi_workspace_enabled(self) -> bool:
+        return True
+
+    def validate(self, expected_instance_uuid: str, *, now: int | None = None) -> None:
+        current_time = int(time.time()) if now is None else now
+        if not self.instance_uuid or self.instance_uuid != expected_instance_uuid:
+            raise CloudBootstrapError('Verified Cloud Manifest targets another LangBot instance')
+        if not self.manifest_jti or not self.verification_key_id:
+            raise CloudBootstrapError('Verified Cloud Manifest receipt is incomplete')
+        if isinstance(self.manifest_generation, bool) or self.manifest_generation <= 0:
+            raise CloudBootstrapError('Verified Cloud Manifest generation must be positive')
+        if self.expires_at <= current_time:
+            raise CloudBootstrapError('Verified Cloud Manifest is expired')
+        if self.tenant_isolation_version < REQUIRED_TENANT_ISOLATION_VERSION:
+            raise CloudBootstrapError('Verified Cloud Manifest requires an unsupported tenant isolation version')
+        if 'multi_workspace_v2' not in self.capabilities:
+            raise CloudBootstrapError('Verified Cloud Manifest does not grant multi_workspace_v2')
+        if not isinstance(self.entitlement_provider, EntitlementProvider):
+            raise CloudBootstrapError('Verified Cloud bootstrap did not provide an entitlement adapter')
+
+    def validate_instance_config(self, config: dict[str, Any]) -> None:
+        if config.get('database', {}).get('use') != 'postgresql':
+            raise CloudBootstrapError('Cloud runtime requires database.use=postgresql')
+        if config.get('vdb', {}).get('use') != self.required_vector_backend:
+            raise CloudBootstrapError('Cloud runtime requires vdb.use=pgvector')
+        if config.get('mcp', {}).get('stdio', {}).get('enabled', True) is not False:
+            raise CloudBootstrapError('Cloud runtime requires mcp.stdio.enabled=false')
+
+
+class CloudBootstrapProvider(Protocol):
+    def bootstrap(
+        self,
+        *,
+        instance_uuid: str,
+        instance_config: dict[str, Any],
+    ) -> VerifiedCloudDeployment | Awaitable[VerifiedCloudDeployment]: ...
+
+
+async def _invoke_provider(
+    loaded: Any,
+    *,
+    instance_uuid: str,
+    instance_config: dict[str, Any],
+) -> VerifiedCloudDeployment:
+    provider = loaded() if inspect.isclass(loaded) else loaded
+    bootstrap = getattr(provider, 'bootstrap', None)
+    if not callable(bootstrap):
+        raise CloudBootstrapError('Cloud bootstrap entry point must expose bootstrap()')
+    result = bootstrap(instance_uuid=instance_uuid, instance_config=instance_config)
+    if inspect.isawaitable(result):
+        result = await result
+    if not isinstance(result, VerifiedCloudDeployment):
+        raise CloudBootstrapError('Cloud bootstrap must return VerifiedCloudDeployment')
+    return result
+
+
+async def resolve_deployment(
+    *,
+    instance_uuid: str,
+    instance_config: dict[str, Any],
+    entry_points: Callable[[], Any] | None = None,
+    now: int | None = None,
+) -> OpenSourceDeployment | VerifiedCloudDeployment:
+    """Discover the optional closed bootstrap and validate its receipt.
+
+    Absence selects OSS singleton mode.  Presence is fail-closed: duplicate,
+    broken, invalid, or expired providers never fall back to an OSS Workspace.
+    """
+
+    discover = entry_points or importlib.metadata.entry_points
+    discovered = discover()
+    if hasattr(discovered, 'select'):
+        candidates = list(discovered.select(group=CLOUD_BOOTSTRAP_ENTRY_POINT))
+    else:  # Python/importlib compatibility for dict-like EntryPoints
+        candidates = list(discovered.get(CLOUD_BOOTSTRAP_ENTRY_POINT, ()))
+    if not candidates:
+        deployment = OpenSourceDeployment()
+        deployment.validate_instance_config(instance_config)
+        return deployment
+    if len(candidates) != 1:
+        raise CloudBootstrapError('Exactly one Cloud bootstrap provider may be installed')
+
+    try:
+        loaded = candidates[0].load()
+        deployment = await _invoke_provider(
+            loaded,
+            instance_uuid=instance_uuid,
+            instance_config=instance_config,
+        )
+        deployment.validate(instance_uuid, now=now)
+        deployment.validate_instance_config(instance_config)
+        return deployment
+    except CloudBootstrapError:
+        raise
+    except Exception as exc:
+        raise CloudBootstrapError('Closed Cloud bootstrap failed') from exc

src/langbot/pkg/cloud/entitlements.py

@@ -0,0 +1,142 @@
+from __future__ import annotations
+
+import asyncio
+import json
+import time
+from typing import Protocol, runtime_checkable
+
+import pydantic
+
+
+class EntitlementUnavailableError(RuntimeError):
+    """Raised when a trusted, currently-active entitlement is unavailable."""
+
+
+class EntitlementSnapshot(pydantic.BaseModel):
+    """Plan-agnostic capability projection consumed by open-source Core.
+
+    Product and billing names deliberately do not appear here.  The closed
+    Control Plane maps subscriptions to these generic features and limits.
+    """
+
+    model_config = pydantic.ConfigDict(frozen=True, extra='forbid')
+
+    instance_uuid: str = pydantic.Field(min_length=1, max_length=256)
+    workspace_uuid: str = pydantic.Field(min_length=1, max_length=256)
+    entitlement_revision: int = pydantic.Field(ge=1)
+    status: str = pydantic.Field(pattern=r'^(active|suspended|cancelled)$')
+    not_before: int = pydantic.Field(ge=0)
+    expires_at: int = pydantic.Field(gt=0)
+    features: dict[str, bool] = pydantic.Field(default_factory=dict)
+    limits: dict[str, int] = pydantic.Field(default_factory=dict)
+
+    @pydantic.field_validator('features')
+    @classmethod
+    def _validate_feature_names(cls, value: dict[str, bool]) -> dict[str, bool]:
+        if any(not str(name).strip() for name in value):
+            raise ValueError('Entitlement feature names must be non-empty')
+        return dict(value)
+
+    @pydantic.field_validator('limits')
+    @classmethod
+    def _validate_limits(cls, value: dict[str, int]) -> dict[str, int]:
+        normalized: dict[str, int] = {}
+        for name, limit in value.items():
+            if not str(name).strip():
+                raise ValueError('Entitlement limit names must be non-empty')
+            if isinstance(limit, bool) or not isinstance(limit, int) or limit < 0:
+                raise ValueError(f'Entitlement limit {name!r} must be a non-negative integer')
+            normalized[str(name)] = limit
+        return normalized
+
+    def require_active(
+        self,
+        *,
+        instance_uuid: str,
+        workspace_uuid: str,
+        now: int | None = None,
+    ) -> EntitlementSnapshot:
+        current_time = int(time.time()) if now is None else now
+        if self.instance_uuid != instance_uuid or self.workspace_uuid != workspace_uuid:
+            raise EntitlementUnavailableError('Entitlement scope does not match the Workspace execution context')
+        if self.status != 'active':
+            raise EntitlementUnavailableError('Workspace entitlement is not active')
+        if current_time < self.not_before or current_time >= self.expires_at:
+            raise EntitlementUnavailableError('Workspace entitlement is not currently valid')
+        return self
+
+    def require_feature(self, feature: str) -> None:
+        if self.features.get(feature) is not True:
+            raise EntitlementUnavailableError(f'Workspace entitlement does not grant {feature}')
+
+    def limit(self, name: str) -> int:
+        value = self.limits.get(name)
+        if value is None:
+            raise EntitlementUnavailableError(f'Workspace entitlement does not define limit {name}')
+        return value
+
+
+@runtime_checkable
+class EntitlementProvider(Protocol):
+    """Closed Control Plane adapter injected by a verified Cloud bootstrap."""
+
+    async def get_workspace_entitlement(self, workspace_uuid: str) -> EntitlementSnapshot:
+        """Return the newest verified snapshot for one Workspace."""
+
+
+class OpenSourceEntitlementProvider:
+    """Marker provider for OSS; Cloud admission grants never use this class."""
+
+    async def get_workspace_entitlement(self, workspace_uuid: str) -> EntitlementSnapshot:
+        del workspace_uuid
+        raise EntitlementUnavailableError('Signed Workspace entitlements are only available in Cloud mode')
+
+
+class EntitlementResolver:
+    """Validate scope/freshness and reject revision rollback or equivocation."""
+
+    def __init__(self, instance_uuid: str, provider: EntitlementProvider) -> None:
+        self.instance_uuid = instance_uuid
+        self.provider = provider
+        self._lock = asyncio.Lock()
+        self._snapshots: dict[str, tuple[int, str, EntitlementSnapshot]] = {}
+
+    @staticmethod
+    def _fingerprint(snapshot: EntitlementSnapshot) -> str:
+        return json.dumps(snapshot.model_dump(mode='json'), sort_keys=True, separators=(',', ':'))
+
+    async def resolve(
+        self,
+        workspace_uuid: str,
+        *,
+        minimum_revision: int = 0,
+        now: int | None = None,
+    ) -> EntitlementSnapshot:
+        candidate = await self.provider.get_workspace_entitlement(workspace_uuid)
+        if not isinstance(candidate, EntitlementSnapshot):
+            raise EntitlementUnavailableError('Entitlement provider returned an invalid snapshot')
+        # Deep-copy untrusted provider-owned containers before caching them.
+        candidate = EntitlementSnapshot.model_validate(candidate.model_dump())
+        candidate.require_active(
+            instance_uuid=self.instance_uuid,
+            workspace_uuid=workspace_uuid,
+            now=now,
+        )
+        if candidate.entitlement_revision < minimum_revision:
+            raise EntitlementUnavailableError('Workspace entitlement revision rolled back')
+
+        fingerprint = self._fingerprint(candidate)
+        async with self._lock:
+            previous = self._snapshots.get(workspace_uuid)
+            if previous is not None:
+                previous_revision, previous_fingerprint, _ = previous
+                if candidate.entitlement_revision < previous_revision:
+                    raise EntitlementUnavailableError('Workspace entitlement revision rolled back')
+                if candidate.entitlement_revision == previous_revision and fingerprint != previous_fingerprint:
+                    raise EntitlementUnavailableError('Workspace entitlement revision has conflicting contents')
+            self._snapshots[workspace_uuid] = (
+                candidate.entitlement_revision,
+                fingerprint,
+                candidate,
+            )
+        return candidate.model_copy(deep=True)

src/langbot/pkg/core/app.py

@@ -48,6 +48,8 @@ from ..survey import manager as survey_module
 from ..skill import manager as skill_mgr
 from ..workspace import service as workspace_service_module
 from ..workspace import collaboration as workspace_collaboration_module
+from ..cloud import bootstrap as cloud_bootstrap_module
+from ..cloud import entitlements as cloud_entitlements_module
 from ..api.http.context import ExecutionContext, PrincipalContext, PrincipalType
 from ..entity.persistence.workspace import WorkspaceExecutionState, WorkspaceExecutionStatus
 
@@ -128,6 +130,10 @@ class Application:
 
     workspace_collaboration_service: workspace_collaboration_module.WorkspaceCollaborationService = None
 
+    deployment: cloud_bootstrap_module.OpenSourceDeployment | cloud_bootstrap_module.VerifiedCloudDeployment = None
+
+    entitlement_resolver: cloud_entitlements_module.EntitlementResolver | None = None
+
     vector_db_mgr: vectordb_mgr.VectorDBManager = None
 
     http_ctrl: http_controller.HTTPController = None

src/langbot/pkg/core/stages/build_app.py

@@ -3,7 +3,7 @@ from __future__ import annotations
 import asyncio
 
 from .. import stage, app
-from ...utils import version, proxy
+from ...utils import version, proxy, constants
 from ...pipeline import pool, controller, pipelinemgr
 from ...pipeline import aggregator as message_aggregator
 from ...box import service as box_service
@@ -41,7 +41,8 @@ from ...telemetry import telemetry as telemetry_module
 from ...survey import manager as survey_module
 from ...workspace import service as workspace_service_module
 from ...workspace import collaboration as workspace_collaboration_module
-from ...workspace import policy as workspace_policy_module
+from ...cloud import bootstrap as cloud_bootstrap
+from ...cloud.entitlements import EntitlementResolver
 from ...api.http.context import ExecutionContext, PrincipalContext, PrincipalType
 from ...api.http.authz import WorkspaceRequiredError
 
@@ -52,6 +53,20 @@ class BuildAppStage(stage.BootingStage):
 
     async def run(self, ap: app.Application):
         """Build LangBot application"""
+        # Multi-Workspace mode is selected only by an installed closed
+        # bootstrap that returns a verified Manifest receipt. Mutable values
+        # such as system.edition are intentionally absent from this boundary.
+        deployment = await cloud_bootstrap.resolve_deployment(
+            instance_uuid=constants.instance_id,
+            instance_config=ap.instance_config.data,
+        )
+        ap.deployment = deployment
+        ap.entitlement_resolver = (
+            EntitlementResolver(constants.instance_id, deployment.entitlement_provider)
+            if deployment.multi_workspace_enabled
+            else None
+        )
+
         ap.task_mgr = taskmgr.AsyncTaskManager(ap)
 
         discover = discover_engine.ComponentDiscoveryEngine(ap)
@@ -109,16 +124,14 @@ class BuildAppStage(stage.BootingStage):
         await storage_mgr_inst.initialize()
         ap.storage_mgr = storage_mgr_inst
 
-        persistence_mgr_inst = persistencemgr.PersistenceManager(ap)
+        persistence_mgr_inst = persistencemgr.PersistenceManager(
+            ap,
+            mode=persistencemgr.PersistenceMode(deployment.persistence_mode),
+        )
         ap.persistence_mgr = persistence_mgr_inst
         await persistence_mgr_inst.initialize()
 
-        # The open-source Core is intentionally single-Workspace.  A mutable
-        # config value such as ``system.edition`` is product metadata, not a
-        # trust credential, and must never activate SaaS routing.  The closed
-        # Cloud bootstrap will install its verified policy only after checking
-        # a signed InstanceManifest; until that bootstrap exists, fail closed.
-        workspace_policy = workspace_policy_module.open_core_workspace_policy()
+        workspace_policy = deployment.workspace_policy
         workspace_service_inst = workspace_service_module.WorkspaceService(
             ap,
             policy=workspace_policy,

src/langbot/pkg/core/stages/load_config.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import os
+import copy
 from typing import Any
 from langbot.pkg.utils import constants
 import yaml
@@ -12,6 +13,44 @@ from .. import stage, app
 from ..bootutils import config
 
 
+_RUNTIME_POLICY_DEFAULTS = {
+    'plugin': {
+        'worker': {
+            'max_cpus': 1.0,
+            'max_memory_mb': 512,
+            'max_pids': 128,
+            'max_open_files': 256,
+            'max_file_size_mb': 512,
+        }
+    },
+    'mcp': {'stdio': {'enabled': True}},
+}
+
+
+def _complete_runtime_policy_defaults(cfg: dict) -> dict:
+    """Backfill typed security-policy leaves before applying env overrides.
+
+    The historic config loader intentionally does not deep-complete the whole
+    template.  These fields are different: their native env overrides must
+    retain boolean/numeric types on upgraded instances, so their defaults must
+    exist before ``PLUGIN__...`` and ``MCP__...`` are parsed.
+    """
+
+    def merge(target: dict, defaults: dict, path: tuple[str, ...] = ()) -> None:
+        for key, default in defaults.items():
+            if key not in target:
+                target[key] = copy.deepcopy(default)
+                continue
+            if isinstance(default, dict):
+                if not isinstance(target[key], dict):
+                    dotted_path = '.'.join((*path, key))
+                    raise ValueError(f'{dotted_path} must be a mapping')
+                merge(target[key], default, (*path, key))
+
+    merge(cfg, _RUNTIME_POLICY_DEFAULTS)
+    return cfg
+
+
 def _apply_env_overrides_to_config(cfg: dict) -> dict:
     """Apply environment variable overrides to data/config.yaml
 
@@ -150,6 +189,10 @@ class LoadConfigStage(stage.BootingStage):
 
         ap.instance_config = await config.load_yaml_config('data/config.yaml', 'config.yaml', completion=False)
 
+        # Deep-complete only typed execution-policy fields. This keeps native
+        # env coercion reliable for existing data/config.yaml files.
+        ap.instance_config.data = _complete_runtime_policy_defaults(ap.instance_config.data)
+
         # Apply environment variable overrides to data/config.yaml
         ap.instance_config.data = _apply_env_overrides_to_config(ap.instance_config.data)
 

src/langbot/pkg/persistence/alembic/versions/0011_postgres_tenant_rls.py

@@ -0,0 +1,130 @@
+"""enforce PostgreSQL tenant isolation with row-level security
+
+Revision ID: 0011_postgres_tenant_rls
+Revises: 0010_scope_resources
+Create Date: 2026-07-19
+
+The table list is deliberately duplicated from the runtime contract. Alembic
+revisions must remain self-contained after application code evolves.
+"""
+
+from __future__ import annotations
+
+import sqlalchemy as sa
+from alembic import op
+
+revision = '0011_postgres_tenant_rls'
+down_revision = '0010_scope_resources'
+branch_labels = None
+depends_on = None
+
+
+_POLICY_NAME = 'langbot_workspace_isolation'
+_TENANT_SETTING = 'langbot.workspace_uuid'
+_OSS_WORKSPACE_METADATA_KEY = 'oss_workspace_uuid'
+_TENANT_TABLE_COLUMNS: dict[str, str] = {
+    'workspaces': 'uuid',
+    'workspace_memberships': 'workspace_uuid',
+    'workspace_invitations': 'workspace_uuid',
+    'workspace_execution_states': 'workspace_uuid',
+    'workspace_metadata': 'workspace_uuid',
+    'api_keys': 'workspace_uuid',
+    'bots': 'workspace_uuid',
+    'bot_admins': 'workspace_uuid',
+    'binary_storages': 'workspace_uuid',
+    'mcp_servers': 'workspace_uuid',
+    'model_providers': 'workspace_uuid',
+    'llm_models': 'workspace_uuid',
+    'embedding_models': 'workspace_uuid',
+    'rerank_models': 'workspace_uuid',
+    'legacy_pipelines': 'workspace_uuid',
+    'pipeline_run_records': 'workspace_uuid',
+    'plugin_settings': 'workspace_uuid',
+    'knowledge_bases': 'workspace_uuid',
+    'knowledge_base_files': 'workspace_uuid',
+    'knowledge_base_chunks': 'workspace_uuid',
+    'webhooks': 'workspace_uuid',
+    'monitoring_messages': 'workspace_uuid',
+    'monitoring_llm_calls': 'workspace_uuid',
+    'monitoring_tool_calls': 'workspace_uuid',
+    'monitoring_sessions': 'workspace_uuid',
+    'monitoring_errors': 'workspace_uuid',
+    'monitoring_embedding_calls': 'workspace_uuid',
+    'monitoring_feedback': 'workspace_uuid',
+}
+
+
+def _quote_identifier(conn: sa.Connection, identifier: str) -> str:
+    return conn.dialect.identifier_preparer.quote(identifier)
+
+
+def _record_oss_workspace_scope(conn: sa.Connection) -> None:
+    """Keep PostgreSQL OSS usable after FORCE RLS is enabled.
+
+    The runtime reads this instance-level metadata and installs the singleton
+    Workspace as a transaction-local default. Cloud databases have no local
+    Workspace and therefore do not receive this compatibility value.
+    """
+    local_workspaces = (
+        conn.execute(sa.text("SELECT uuid FROM workspaces WHERE source = 'local' ORDER BY uuid")).scalars().all()
+    )
+    if len(local_workspaces) != 1:
+        return
+
+    existing = conn.execute(
+        sa.text('SELECT value FROM metadata WHERE key = :key'),
+        {'key': _OSS_WORKSPACE_METADATA_KEY},
+    ).scalar_one_or_none()
+    if existing is None:
+        conn.execute(
+            sa.text('INSERT INTO metadata (key, value) VALUES (:key, :value)'),
+            {'key': _OSS_WORKSPACE_METADATA_KEY, 'value': local_workspaces[0]},
+        )
+    elif existing != local_workspaces[0]:
+        raise RuntimeError('Stored OSS Workspace scope does not match the local Workspace')
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    if conn.dialect.name != 'postgresql':
+        return
+
+    existing_tables = set(sa.inspect(conn).get_table_names())
+    missing_tables = set(_TENANT_TABLE_COLUMNS) - existing_tables
+    if missing_tables:
+        raise RuntimeError(f'Cannot enable tenant RLS before all tenant-owned tables exist: {sorted(missing_tables)!r}')
+
+    _record_oss_workspace_scope(conn)
+
+    policy_name = _quote_identifier(conn, _POLICY_NAME)
+    for table_name, tenant_column in _TENANT_TABLE_COLUMNS.items():
+        table = _quote_identifier(conn, table_name)
+        column = _quote_identifier(conn, tenant_column)
+        tenant_value = f"CAST(NULLIF(current_setting('{_TENANT_SETTING}', true), '') AS VARCHAR(36))"
+
+        op.execute(sa.text(f'ALTER TABLE {table} ENABLE ROW LEVEL SECURITY'))
+        op.execute(sa.text(f'ALTER TABLE {table} FORCE ROW LEVEL SECURITY'))
+        op.execute(sa.text(f'DROP POLICY IF EXISTS {policy_name} ON {table}'))
+        op.execute(
+            sa.text(
+                f'CREATE POLICY {policy_name} ON {table} '
+                f'USING ({column} = {tenant_value}) '
+                f'WITH CHECK ({column} = {tenant_value})'
+            )
+        )
+
+
+def downgrade() -> None:
+    conn = op.get_bind()
+    if conn.dialect.name != 'postgresql':
+        return
+
+    existing_tables = set(sa.inspect(conn).get_table_names())
+    policy_name = _quote_identifier(conn, _POLICY_NAME)
+    for table_name in _TENANT_TABLE_COLUMNS:
+        if table_name not in existing_tables:
+            continue
+        table = _quote_identifier(conn, table_name)
+        op.execute(sa.text(f'DROP POLICY IF EXISTS {policy_name} ON {table}'))
+        op.execute(sa.text(f'ALTER TABLE {table} NO FORCE ROW LEVEL SECURITY'))
+        op.execute(sa.text(f'ALTER TABLE {table} DISABLE ROW LEVEL SECURITY'))

src/langbot/pkg/persistence/alembic_runner.py

@@ -18,6 +18,7 @@ from typing import TYPE_CHECKING
 from alembic.config import Config
 from alembic import command
 from alembic.runtime.migration import MigrationContext
+from alembic.script import ScriptDirectory
 
 if TYPE_CHECKING:
     from sqlalchemy.ext.asyncio import AsyncEngine
@@ -59,6 +60,16 @@ def _do_get_current(connection: Connection) -> str | None:
     return ctx.get_current_revision()
 
 
+def get_alembic_head() -> str:
+    """Resolve the single release head without opening a database connection."""
+    cfg = Config()
+    cfg.set_main_option('script_location', _ALEMBIC_DIR)
+    head = ScriptDirectory.from_config(cfg).get_current_head()
+    if head is None:
+        raise RuntimeError('Alembic has no migration head')
+    return head
+
+
 def _do_autogenerate(connection: Connection, message: str = 'auto migration') -> None:
     """Synchronous autogenerate — runs inside run_sync."""
     cfg = _build_config(connection)

src/langbot/pkg/persistence/mgr.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import datetime
+import enum
 import sqlite3
 import typing
 
@@ -15,6 +16,7 @@ from ..entity import persistence
 from ..core import app
 from ..utils import constants, importutil
 from . import databases, migrations
+from .tenant_uow import TENANT_POLICY_NAME, TENANT_SETTING, TENANT_TABLE_COLUMNS, TenantUnitOfWork
 
 importutil.import_modules_in_pkg(databases)
 importutil.import_modules_in_pkg(migrations)
@@ -64,6 +66,15 @@ _PRE_WORKSPACE_ALEMBIC_REVISIONS = {
 }
 _WORKSPACE_ALEMBIC_REVISION = '0009_workspace_tenancy'
 _RESOURCE_SCOPE_ALEMBIC_REVISION = '0010_scope_resources'
+_OSS_WORKSPACE_METADATA_KEY = 'oss_workspace_uuid'
+
+
+class PersistenceMode(enum.StrEnum):
+    """Trusted persistence startup mode selected by the process entrypoint."""
+
+    OSS_COMPAT = 'oss_compat'
+    CLOUD_RUNTIME = 'cloud_runtime'
+    RELEASE_MIGRATION = 'release_migration'
 
 
 class PersistenceManager:
@@ -76,9 +87,12 @@ class PersistenceManager:
 
     meta: sqlalchemy.MetaData
 
-    def __init__(self, ap: app.Application):
+    def __init__(self, ap: app.Application, *, mode: PersistenceMode = PersistenceMode.OSS_COMPAT):
+        if not isinstance(mode, PersistenceMode):
+            raise TypeError('PersistenceManager mode must be a trusted PersistenceMode value')
         self.ap = ap
         self.meta = base.Base.metadata
+        self.mode = mode
 
     async def initialize(self):
         database_type = self.ap.instance_config.data.get('database', {}).get('use', 'sqlite')
@@ -89,7 +103,27 @@ class PersistenceManager:
                 await self.db.initialize()
                 break
 
+        engine = self.get_db_engine()
+        if self.mode in {PersistenceMode.CLOUD_RUNTIME, PersistenceMode.RELEASE_MIGRATION}:
+            if engine.dialect.name != 'postgresql':
+                raise RuntimeError(f'{self.mode.value} persistence mode requires PostgreSQL')
+
+        if self.mode == PersistenceMode.CLOUD_RUNTIME:
+            await self._validate_cloud_runtime()
+            return
+
         self._enable_sqlite_foreign_keys()
+        await self._initialize_managed_schema()
+
+        if self.mode == PersistenceMode.OSS_COMPAT:
+            await self.write_space_model_providers()
+
+    async def _initialize_managed_schema(self) -> None:
+        """Create or migrate schema only in OSS and release processes."""
+        from . import alembic_runner
+
+        engine = self.get_db_engine()
+        release_bootstrap = self.mode == PersistenceMode.RELEASE_MIGRATION and await self._is_empty_schema()
 
         await self.create_tables()
 
@@ -125,16 +159,36 @@ class PersistenceManager:
 
             self.ap.logger.info(f'Successfully upgraded database to version {last_migration_number}.')
 
-        # Run Alembic migrations (new migration system)
-        await self._run_alembic_migrations()
+        if engine.dialect.name == 'postgresql':
+            current_revision = await alembic_runner.get_alembic_current(engine)
+            head_revision = alembic_runner.get_alembic_head()
 
-        # A legacy database may not contain tenant tables introduced by a
-        # newer release.  They were deliberately deferred before 0009 because
-        # their Workspace/account FK targets did not exist yet; create them
-        # now that the tenancy contract is in place.
-        await self.create_tables()
+            if release_bootstrap:
+                # Base.metadata represents the complete 0010 schema. An empty
+                # Cloud database has no legacy data to transform and must not
+                # run 0009's OSS singleton Workspace bootstrap.
+                if current_revision is not None:
+                    raise RuntimeError('Empty PostgreSQL release bootstrap unexpectedly has an Alembic revision')
+                await alembic_runner.run_alembic_stamp(engine, _RESOURCE_SCOPE_ALEMBIC_REVISION)
+            elif current_revision != head_revision:
+                # A legacy database may not contain tenant tables introduced
+                # by a newer release. Upgrade the account/resource contract,
+                # then create deferred tables before the RLS migration runs.
+                await self._run_alembic_migrations(_RESOURCE_SCOPE_ALEMBIC_REVISION)
+                await self.create_tables()
 
-        await self.write_space_model_providers()
+            await self._run_alembic_migrations()
+            await self._validate_postgres_tenant_schema(validate_runtime_role=False)
+
+            if self.mode == PersistenceMode.OSS_COMPAT:
+                await self._install_oss_postgres_tenant_scope()
+        else:
+            await self._run_alembic_migrations()
+
+            # SQLite keeps the historical post-migration create_all pass. New
+            # tenant tables are deferred until the Workspace/account schema is
+            # compatible with their foreign keys.
+            await self.create_tables()
 
     async def create_tables(self):
         async with self.get_db_engine().connect() as conn:
@@ -173,6 +227,37 @@ class PersistenceManager:
 
         await self._ensure_instance_uuid_metadata()
 
+    async def _is_empty_schema(self) -> bool:
+        async with self.get_db_engine().connect() as conn:
+            table_names = await conn.run_sync(lambda sync_conn: set(sqlalchemy.inspect(sync_conn).get_table_names()))
+        return not table_names
+
+    async def _install_oss_postgres_tenant_scope(self) -> None:
+        """Default every OSS PostgreSQL transaction to its singleton Workspace."""
+        if getattr(self, '_oss_tenant_scope_listener_installed', False):
+            return
+
+        async with self.get_db_engine().connect() as conn:
+            workspace_uuid = await conn.scalar(
+                sqlalchemy.select(metadata.Metadata.value).where(
+                    metadata.Metadata.key == _OSS_WORKSPACE_METADATA_KEY,
+                )
+            )
+        if not isinstance(workspace_uuid, str) or not workspace_uuid.strip():
+            raise RuntimeError(
+                'PostgreSQL OSS mode requires exactly one local Workspace recorded before tenant RLS is enabled'
+            )
+        workspace_uuid = workspace_uuid.strip()
+
+        def set_oss_tenant_scope(conn: sqlalchemy.Connection) -> None:
+            conn.execute(
+                sqlalchemy.text(f"SELECT set_config('{TENANT_SETTING}', :workspace_uuid, true)"),
+                {'workspace_uuid': workspace_uuid},
+            )
+
+        sqlalchemy.event.listen(self.get_db_engine().sync_engine, 'begin', set_oss_tenant_scope)
+        self._oss_tenant_scope_listener_installed = True
+
     def _enable_sqlite_foreign_keys(self) -> None:
         """Enable SQLite FK enforcement for every pooled runtime connection."""
         engine = self.get_db_engine()
@@ -215,6 +300,122 @@ class PersistenceManager:
                 f'{runtime_instance_uuid!r} != {persisted_instance_uuid!r}'
             )
 
+    async def _validate_cloud_runtime(self) -> None:
+        """Validate a release-prepared schema without performing any DDL."""
+        from . import alembic_runner
+
+        engine = self.get_db_engine()
+        current_revision = await alembic_runner.get_alembic_current(engine)
+        head_revision = alembic_runner.get_alembic_head()
+        if current_revision != head_revision:
+            raise RuntimeError(
+                f'Cloud runtime database schema is not at the release head: {current_revision!r} != {head_revision!r}'
+            )
+
+        runtime_instance_uuid = constants.instance_id.strip()
+        if not runtime_instance_uuid:
+            raise RuntimeError('LangBot instance UUID is empty before Cloud persistence validation')
+        async with engine.connect() as conn:
+            persisted_instance_uuid = await conn.scalar(
+                sqlalchemy.select(metadata.Metadata.value).where(metadata.Metadata.key == 'instance_uuid')
+            )
+        if persisted_instance_uuid is None:
+            raise RuntimeError("Cloud runtime database is missing metadata['instance_uuid']")
+        if persisted_instance_uuid != runtime_instance_uuid:
+            raise RuntimeError(
+                'LangBot instance UUID does not match the value bound to this database: '
+                f'{runtime_instance_uuid!r} != {persisted_instance_uuid!r}'
+            )
+
+        await self._validate_postgres_tenant_schema(validate_runtime_role=True)
+
+    async def _validate_postgres_tenant_schema(self, *, validate_runtime_role: bool) -> None:
+        """Fail closed when PostgreSQL cannot enforce the tenant contract."""
+        engine = self.get_db_engine()
+        if engine.dialect.name != 'postgresql':
+            raise RuntimeError('PostgreSQL tenant schema validation requires PostgreSQL')
+
+        table_query = sqlalchemy.text(
+            """
+            SELECT
+                c.relname AS table_name,
+                c.relrowsecurity AS rls_enabled,
+                c.relforcerowsecurity AS rls_forced,
+                pg_get_userbyid(c.relowner) = current_user AS owned_by_runtime,
+                EXISTS (
+                    SELECT 1
+                    FROM pg_policy p
+                    WHERE p.polrelid = c.oid
+                      AND p.polname = :policy_name
+                      AND p.polcmd = '*'
+                      AND p.polpermissive
+                      AND p.polqual IS NOT NULL
+                      AND p.polwithcheck IS NOT NULL
+                ) AS policy_valid
+            FROM pg_class c
+            JOIN pg_namespace n ON n.oid = c.relnamespace
+            WHERE n.nspname = current_schema()
+              AND c.relkind IN ('r', 'p')
+              AND c.relname IN :table_names
+            """
+        ).bindparams(sqlalchemy.bindparam('table_names', expanding=True))
+
+        async with engine.connect() as conn:
+            if validate_runtime_role:
+                role = (
+                    (
+                        await conn.execute(
+                            sqlalchemy.text(
+                                """
+                            SELECT rolsuper, rolbypassrls
+                            FROM pg_roles
+                            WHERE rolname = current_user
+                            """
+                            )
+                        )
+                    )
+                    .mappings()
+                    .one_or_none()
+                )
+                if role is None:
+                    raise RuntimeError('Cloud runtime PostgreSQL role could not be inspected')
+                if role['rolsuper']:
+                    raise RuntimeError('Cloud runtime PostgreSQL role must not be a superuser')
+                if role['rolbypassrls']:
+                    raise RuntimeError('Cloud runtime PostgreSQL role must not have BYPASSRLS')
+
+            rows = (
+                (
+                    await conn.execute(
+                        table_query,
+                        {
+                            'policy_name': TENANT_POLICY_NAME,
+                            'table_names': tuple(TENANT_TABLE_COLUMNS),
+                        },
+                    )
+                )
+                .mappings()
+                .all()
+            )
+
+        by_table = {row['table_name']: row for row in rows}
+        missing_tables = set(TENANT_TABLE_COLUMNS) - set(by_table)
+        if missing_tables:
+            raise RuntimeError(f'PostgreSQL tenant tables are missing: {sorted(missing_tables)!r}')
+
+        invalid_rls = sorted(
+            table_name
+            for table_name, row in by_table.items()
+            if not row['rls_enabled'] or not row['rls_forced'] or not row['policy_valid']
+        )
+        if invalid_rls:
+            raise RuntimeError(f'PostgreSQL tenant RLS contract is incomplete for tables: {invalid_rls!r}')
+
+        if validate_runtime_role:
+            owned_tables = sorted(table_name for table_name, row in by_table.items() if row['owned_by_runtime'])
+            if owned_tables:
+                raise RuntimeError(f'Cloud runtime PostgreSQL role must not own tenant tables: {owned_tables!r}')
+
     async def write_space_model_providers(self):
         if constants.edition != 'community':
             # SaaS Workspace/provider linkage is explicit control-plane state;
@@ -277,7 +478,7 @@ class PersistenceManager:
 
     # =================================
 
-    async def _run_alembic_migrations(self):
+    async def _run_alembic_migrations(self, target_revision: str = 'head'):
         """Run Alembic-based migrations after legacy migrations complete."""
         from . import alembic_runner
 
@@ -310,8 +511,8 @@ class PersistenceManager:
             # PostgreSQL has transactional DDL. SQLite has already crossed the
             # two destructive tenancy boundaries under verified backups; this
             # final call is a no-op today and applies future migrations.
-            await alembic_runner.run_alembic_upgrade(engine, 'head')
-            self.ap.logger.info('Alembic migrations completed.')
+            await alembic_runner.run_alembic_upgrade(engine, target_revision)
+            self.ap.logger.info(f'Alembic migrations completed at {target_revision}.')
         except Exception as e:
             self.ap.logger.error(f'Alembic migration failed: {e}', exc_info=True)
             raise
@@ -359,6 +560,9 @@ class PersistenceManager:
             await conn.commit()
             return result
 
+    def tenant_uow(self, workspace_uuid: str) -> TenantUnitOfWork:
+        return TenantUnitOfWork(self.get_db_engine(), workspace_uuid)
+
     def get_db_engine(self) -> sqlalchemy_asyncio.AsyncEngine:
         return self.db.get_engine()
 

src/langbot/pkg/persistence/tenant_uow.py

@@ -0,0 +1,113 @@
+from __future__ import annotations
+
+import types
+import typing
+
+import sqlalchemy
+import sqlalchemy.ext.asyncio as sqlalchemy_asyncio
+
+
+TENANT_SETTING = 'langbot.workspace_uuid'
+TENANT_POLICY_NAME = 'langbot_workspace_isolation'
+
+# Keep this contract explicit. A new tenant-owned table must be added to both
+# this runtime list and the corresponding Alembic migration before release.
+TENANT_TABLE_COLUMNS: dict[str, str] = {
+    'workspaces': 'uuid',
+    'workspace_memberships': 'workspace_uuid',
+    'workspace_invitations': 'workspace_uuid',
+    'workspace_execution_states': 'workspace_uuid',
+    'workspace_metadata': 'workspace_uuid',
+    'api_keys': 'workspace_uuid',
+    'bots': 'workspace_uuid',
+    'bot_admins': 'workspace_uuid',
+    'binary_storages': 'workspace_uuid',
+    'mcp_servers': 'workspace_uuid',
+    'model_providers': 'workspace_uuid',
+    'llm_models': 'workspace_uuid',
+    'embedding_models': 'workspace_uuid',
+    'rerank_models': 'workspace_uuid',
+    'legacy_pipelines': 'workspace_uuid',
+    'pipeline_run_records': 'workspace_uuid',
+    'plugin_settings': 'workspace_uuid',
+    'knowledge_bases': 'workspace_uuid',
+    'knowledge_base_files': 'workspace_uuid',
+    'knowledge_base_chunks': 'workspace_uuid',
+    'webhooks': 'workspace_uuid',
+    'monitoring_messages': 'workspace_uuid',
+    'monitoring_llm_calls': 'workspace_uuid',
+    'monitoring_tool_calls': 'workspace_uuid',
+    'monitoring_sessions': 'workspace_uuid',
+    'monitoring_errors': 'workspace_uuid',
+    'monitoring_embedding_calls': 'workspace_uuid',
+    'monitoring_feedback': 'workspace_uuid',
+}
+
+
+class TenantUnitOfWork:
+    """Bind one Workspace scope to one database transaction.
+
+    PostgreSQL receives a transaction-local setting used by RLS policies.
+    SQLite keeps the same transaction boundary without a database setting so
+    OSS callers can adopt this API without changing database engines.
+    """
+
+    def __init__(self, engine: sqlalchemy_asyncio.AsyncEngine, workspace_uuid: str) -> None:
+        workspace_uuid = workspace_uuid.strip()
+        if not workspace_uuid:
+            raise ValueError('TenantUnitOfWork requires a non-empty workspace_uuid')
+
+        self._engine = engine
+        self.workspace_uuid = workspace_uuid
+        self._session: sqlalchemy_asyncio.AsyncSession | None = None
+        self._used = False
+
+    @property
+    def session(self) -> sqlalchemy_asyncio.AsyncSession:
+        if self._session is None:
+            raise RuntimeError('TenantUnitOfWork is not active')
+        return self._session
+
+    async def __aenter__(self) -> TenantUnitOfWork:
+        if self._used:
+            raise RuntimeError('TenantUnitOfWork instances cannot be reused')
+        self._used = True
+
+        session = sqlalchemy_asyncio.AsyncSession(self._engine, expire_on_commit=False)
+        self._session = session
+        try:
+            await session.begin()
+            if self._engine.dialect.name == 'postgresql':
+                await session.execute(
+                    sqlalchemy.text(f"SELECT set_config('{TENANT_SETTING}', :workspace_uuid, true)"),
+                    {'workspace_uuid': self.workspace_uuid},
+                )
+        except BaseException:
+            await session.rollback()
+            await session.close()
+            self._session = None
+            raise
+        return self
+
+    async def __aexit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_value: BaseException | None,
+        traceback: types.TracebackType | None,
+    ) -> bool:
+        session = self.session
+        try:
+            if exc_type is None:
+                await session.commit()
+            else:
+                await session.rollback()
+        finally:
+            await session.close()
+            self._session = None
+        return False
+
+    async def execute(self, *args: typing.Any, **kwargs: typing.Any) -> sqlalchemy.engine.Result[typing.Any]:
+        return await self.session.execute(*args, **kwargs)
+
+    async def flush(self) -> None:
+        await self.session.flush()

src/langbot/pkg/provider/tools/loaders/mcp.py

@@ -30,6 +30,7 @@ import langbot_plugin.api.entities.builtin.resource.tool as resource_tool
 import langbot_plugin.api.entities.builtin.provider.message as provider_message
 from ....entity.persistence import mcp as persistence_mcp
 from .mcp_stdio import BoxStdioSessionRuntime, MCPServerBoxConfig, MCPSessionErrorPhase, _ColdStartRetry  # noqa: F401
+from .mcp_policy import require_stdio_mcp_enabled, stdio_mcp_enabled
 
 # Synthesized LLM tools for MCP resources (not from server tools/list).
 # Dispatched in MCPLoader.invoke_tool; placeholder func on LLMTool is never used.
@@ -350,6 +351,11 @@ class RuntimeMCPSession:
         )
 
     async def _init_stdio_python_server(self):
+        # Final transport gate: this must run before both the Box branch and
+        # the backwards-compatible host-stdio branch.  Service/UI checks are
+        # usability guards; this is the execution security boundary.
+        require_stdio_mcp_enabled(self.ap, self.server_config)
+
         if self._uses_box_stdio():
             await self._box_stdio_runtime.initialize()
             return
@@ -1436,6 +1442,12 @@ class MCPLoader(loader.ToolLoader):
 
         for server in servers:
             config = self.ap.persistence_mgr.serialize_model(persistence_mcp.MCPServer, server)
+            if config.get('mode') == 'stdio' and not stdio_mcp_enabled(self.ap):
+                self.ap.logger.info(
+                    f'Skipping disabled stdio MCP server {server.uuid}; '
+                    'the persisted configuration is retained but no process is launched'
+                )
+                continue
             try:
                 binding = await self.ap.workspace_service.get_execution_binding(server.workspace_uuid)
                 execution_context = ExecutionContext(
@@ -1511,6 +1523,7 @@ class MCPLoader(loader.ToolLoader):
         """
         execution_context = await self._assert_execution_active(context)
         server_config = dict(server_config)
+        require_stdio_mcp_enabled(self.ap, server_config)
         configured_workspace = str(server_config.get('workspace_uuid') or '').strip()
         if configured_workspace and configured_workspace != execution_context.workspace_uuid:
             raise ValueError('MCP server configuration belongs to another Workspace')

src/langbot/pkg/provider/tools/loaders/mcp_policy.py

@@ -0,0 +1,50 @@
+from __future__ import annotations
+
+from typing import Any
+
+
+MCP_STDIO_DISABLED_CODE = 'mcp_stdio_disabled'
+MCP_STDIO_DISABLED_MESSAGE = 'Stdio MCP is disabled by instance policy'
+
+
+class MCPStdioDisabledError(RuntimeError):
+    """Raised when an instance-level policy refuses stdio MCP execution."""
+
+    code = MCP_STDIO_DISABLED_CODE
+
+    def __init__(self) -> None:
+        super().__init__(MCP_STDIO_DISABLED_MESSAGE)
+
+
+def stdio_mcp_enabled(ap: Any) -> bool:
+    """Return the independent instance-level stdio MCP feature gate.
+
+    The open-source default remains enabled for backwards compatibility.  A
+    deployment can disable it with ``mcp.stdio.enabled: false`` (or
+    ``MCP__STDIO__ENABLED=false``).  Invalid values fail closed instead of
+    accidentally enabling local process execution.
+    """
+
+    instance_config = getattr(ap, 'instance_config', None)
+    config = getattr(instance_config, 'data', None)
+    if not isinstance(config, dict):
+        return False
+    mcp_config = config.get('mcp', {})
+    if not isinstance(mcp_config, dict):
+        return False
+    stdio_config = mcp_config.get('stdio', {})
+    if not isinstance(stdio_config, dict):
+        return False
+    enabled = stdio_config.get('enabled', True)
+    return enabled if isinstance(enabled, bool) else False
+
+
+def is_stdio_server(server_config: dict[str, Any] | None) -> bool:
+    return isinstance(server_config, dict) and str(server_config.get('mode') or '').strip().lower() == 'stdio'
+
+
+def require_stdio_mcp_enabled(ap: Any, server_config: dict[str, Any] | None) -> None:
+    """Fail closed for a stdio server before choosing Box or host transport."""
+
+    if is_stdio_server(server_config) and not stdio_mcp_enabled(ap):
+        raise MCPStdioDisabledError()

src/langbot/templates/config.yaml

@@ -125,9 +125,22 @@ plugin:
     runtime_ws_url: 'ws://langbot_plugin_runtime:5400/control/ws'
     enable_marketplace: true
     display_plugin_debug_url: 'ws://localhost:5401/plugin/debug/ws'
+    worker:
+        # Instance-wide maximum for every plugin installation. Plugin
+        # manifests cannot raise or override these limits.
+        max_cpus: 1.0
+        max_memory_mb: 512
+        max_pids: 128
+        max_open_files: 256
+        max_file_size_mb: 512
     binary_storage:
         # Max bytes for a single plugin binary storage value
         max_value_bytes: 10485760
+mcp:
+    stdio:
+        # Independent gate for local stdio MCP transports. Cloud v2 sets
+        # MCP__STDIO__ENABLED=false even when Box Runtime is available.
+        enabled: true
 monitoring:
     auto_cleanup:
         # Enable automatic cleanup of expired monitoring records

tests/integration/persistence/test_migrations_postgres.py

@@ -15,15 +15,20 @@ from __future__ import annotations
 
 import logging
 import os
+import uuid
+from types import SimpleNamespace
+from unittest.mock import AsyncMock
+
 import pytest
 import sqlalchemy as sa
 from sqlalchemy.exc import IntegrityError
-from sqlalchemy.ext.asyncio import create_async_engine
+from sqlalchemy.ext.asyncio import AsyncEngine, create_async_engine
 from sqlalchemy import text
 
 from langbot.pkg.entity.persistence.base import Base
 from langbot.pkg.entity.persistence.user import User
-from langbot.pkg.persistence.mgr import PersistenceManager
+from langbot.pkg.persistence.mgr import PersistenceManager, PersistenceMode
+from langbot.pkg.persistence.tenant_uow import TENANT_POLICY_NAME, TENANT_TABLE_COLUMNS, TenantUnitOfWork
 from langbot.pkg.persistence.alembic_runner import (
     run_alembic_upgrade,
     run_alembic_stamp,
@@ -49,6 +54,44 @@ def _get_script_head() -> str:
     return ScriptDirectory.from_config(cfg).get_current_head()
 
 
+def _application_for_postgres_url(postgres_url: str, logger_name: str) -> SimpleNamespace:
+    url = sa.engine.make_url(postgres_url)
+    return SimpleNamespace(
+        instance_config=SimpleNamespace(
+            data={
+                'database': {
+                    'use': 'postgresql',
+                    'postgresql': {
+                        'host': url.host,
+                        'port': url.port,
+                        'user': url.username,
+                        'password': url.password,
+                        'database': url.database,
+                    },
+                }
+            }
+        ),
+        logger=logging.getLogger(logger_name),
+    )
+
+
+async def _dispose_manager(manager: PersistenceManager | None) -> None:
+    if manager is not None and getattr(manager, 'db', None) is not None:
+        await manager.get_db_engine().dispose()
+
+
+def _restore_postgres_manager_registry(monkeypatch) -> None:
+    """Undo the registry isolation used by test_database_decorator.py."""
+    from langbot.pkg.persistence import mgr as persistence_mgr_module
+    from langbot.pkg.persistence.databases.postgresql import PostgreSQLDatabaseManager
+
+    monkeypatch.setattr(
+        persistence_mgr_module.database,
+        'preregistered_managers',
+        [PostgreSQLDatabaseManager],
+    )
+
+
 pytestmark = [pytest.mark.integration, pytest.mark.slow]
 
 
@@ -309,7 +352,7 @@ class TestPostgreSQLWorkspaceMigration:
             )
         assert 'workspaces' not in tables_before_migration
 
-        await manager._run_alembic_migrations()
+        await manager._initialize_managed_schema()
 
         async with postgres_engine.connect() as conn:
             account = (await conn.execute(text('SELECT uuid, status, source FROM users'))).mappings().one()
@@ -425,3 +468,278 @@ class TestPostgreSQLResourceTenancyMigration:
                     ),
                     {'workspace_uuid': second_workspace_uuid},
                 )
+
+
+class TestPostgreSQLTenantRuntime:
+    """Release bootstrap, RLS enforcement, and runtime-role safety."""
+
+    @pytest.mark.asyncio
+    async def test_oss_postgres_defaults_to_the_singleton_workspace(
+        self,
+        postgres_url,
+        clean_tables,
+        clean_alembic_version,
+        monkeypatch,
+    ):
+        instance_uuid = 'oss-postgres-rls-compatibility-test'
+        _restore_postgres_manager_registry(monkeypatch)
+        monkeypatch.setattr(constants, 'instance_id', instance_uuid)
+        manager = PersistenceManager(
+            _application_for_postgres_url(postgres_url, 'postgres-oss-rls-compatibility-test'),
+            mode=PersistenceMode.OSS_COMPAT,
+        )
+        try:
+            await manager.initialize()
+            async with manager.get_db_engine().connect() as conn:
+                workspace_uuid = await conn.scalar(text("SELECT uuid FROM workspaces WHERE source = 'local'"))
+                tenant_setting = await conn.scalar(text("SELECT current_setting('langbot.workspace_uuid', true)"))
+                visible_workspaces = await conn.scalar(text('SELECT COUNT(*) FROM workspaces'))
+            assert workspace_uuid == tenant_setting
+            assert visible_workspaces == 1
+        finally:
+            await _dispose_manager(manager)
+
+    @pytest.mark.asyncio
+    async def test_release_bootstrap_and_runtime_isolation(
+        self,
+        postgres_url,
+        postgres_engine,
+        clean_tables,
+        clean_alembic_version,
+        monkeypatch,
+    ):
+        instance_uuid = 'cloud-runtime-persistence-test'
+        workspace_a = '10000000-0000-0000-0000-000000000001'
+        workspace_b = '20000000-0000-0000-0000-000000000002'
+        role_suffix = uuid.uuid4().hex[:12]
+        runtime_role = f'lb_runtime_{role_suffix}'
+        bypass_role = f'lb_bypass_{role_suffix}'
+        owner_role = f'lb_owner_{role_suffix}'
+        role_password = f'Lb{uuid.uuid4().hex}'
+        created_roles: list[str] = []
+        managers: list[PersistenceManager] = []
+        runtime_engine: AsyncEngine | None = None
+        owner_changed = False
+
+        _restore_postgres_manager_registry(monkeypatch)
+        monkeypatch.setattr(constants, 'instance_id', instance_uuid)
+        release_manager = PersistenceManager(
+            _application_for_postgres_url(postgres_url, 'postgres-release-bootstrap-test'),
+            mode=PersistenceMode.RELEASE_MIGRATION,
+        )
+        managers.append(release_manager)
+
+        async with postgres_engine.connect() as conn:
+            admin_user = await conn.scalar(text('SELECT current_user'))
+        quote = postgres_engine.dialect.identifier_preparer.quote
+
+        def role_url(role_name: str) -> str:
+            return (
+                sa.engine.make_url(postgres_url)
+                .set(
+                    username=role_name,
+                    password=role_password,
+                )
+                .render_as_string(hide_password=False)
+            )
+
+        async def create_role(role_name: str, *, bypass_rls: bool = False) -> None:
+            bypass_clause = ' BYPASSRLS' if bypass_rls else ''
+            async with postgres_engine.connect() as conn:
+                await conn.execute(
+                    text(f"CREATE ROLE {quote(role_name)} LOGIN{bypass_clause} PASSWORD '{role_password}'")
+                )
+                await conn.execute(
+                    text(
+                        f'GRANT CONNECT ON DATABASE {quote(sa.engine.make_url(postgres_url).database)} '
+                        f'TO {quote(role_name)}'
+                    )
+                )
+                await conn.execute(text(f'GRANT USAGE ON SCHEMA public TO {quote(role_name)}'))
+                await conn.execute(
+                    text(f'GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA public TO {quote(role_name)}')
+                )
+                await conn.execute(text(f'GRANT USAGE, SELECT ON ALL SEQUENCES IN SCHEMA public TO {quote(role_name)}'))
+            created_roles.append(role_name)
+
+        try:
+            await release_manager.initialize()
+            release_engine = release_manager.get_db_engine()
+
+            assert await get_alembic_current(release_engine) == _get_script_head()
+            async with release_engine.connect() as conn:
+                assert await conn.scalar(text('SELECT COUNT(*) FROM workspaces')) == 0
+                rls_rows = (
+                    (
+                        await conn.execute(
+                            text(
+                                """
+                            SELECT c.relname, c.relrowsecurity, c.relforcerowsecurity,
+                                   EXISTS (
+                                       SELECT 1 FROM pg_policy p
+                                       WHERE p.polrelid = c.oid AND p.polname = :policy_name
+                                   ) AS has_policy
+                            FROM pg_class c
+                            JOIN pg_namespace n ON n.oid = c.relnamespace
+                            WHERE n.nspname = current_schema() AND c.relname IN :table_names
+                            """
+                            ).bindparams(sa.bindparam('table_names', expanding=True)),
+                            {
+                                'policy_name': TENANT_POLICY_NAME,
+                                'table_names': tuple(TENANT_TABLE_COLUMNS),
+                            },
+                        )
+                    )
+                    .mappings()
+                    .all()
+                )
+            assert {row['relname'] for row in rls_rows} == set(TENANT_TABLE_COLUMNS)
+            assert all(row['relrowsecurity'] and row['relforcerowsecurity'] and row['has_policy'] for row in rls_rows)
+
+            for workspace_uuid, slug in ((workspace_a, 'workspace-a'), (workspace_b, 'workspace-b')):
+                async with TenantUnitOfWork(release_engine, workspace_uuid) as uow:
+                    await uow.execute(
+                        text(
+                            """
+                            INSERT INTO workspaces
+                                (uuid, instance_uuid, name, slug, type, status, source, projection_revision)
+                            VALUES
+                                (:uuid, :instance_uuid, :name, :slug, 'team', 'active', 'cloud_projection', 0)
+                            """
+                        ),
+                        {
+                            'uuid': workspace_uuid,
+                            'instance_uuid': instance_uuid,
+                            'name': slug,
+                            'slug': slug,
+                        },
+                    )
+                    await uow.execute(
+                        text(
+                            'INSERT INTO workspace_metadata (workspace_uuid, key, value) '
+                            "VALUES (:workspace_uuid, 'seed', :value)"
+                        ),
+                        {'workspace_uuid': workspace_uuid, 'value': slug},
+                    )
+
+            await create_role(runtime_role)
+            runtime_engine = create_async_engine(role_url(runtime_role), pool_size=1, max_overflow=0)
+
+            async with runtime_engine.connect() as conn:
+                assert (await conn.execute(text('SELECT uuid FROM workspaces'))).all() == []
+                assert (await conn.execute(text('SELECT * FROM workspace_metadata'))).all() == []
+
+            with pytest.raises(sa.exc.DBAPIError):
+                async with runtime_engine.begin() as conn:
+                    await conn.execute(
+                        text(
+                            'INSERT INTO workspace_metadata (workspace_uuid, key, value) '
+                            "VALUES (:workspace_uuid, 'no-scope', 'rejected')"
+                        ),
+                        {'workspace_uuid': workspace_a},
+                    )
+
+            async with TenantUnitOfWork(runtime_engine, workspace_a) as uow:
+                assert (await uow.execute(text('SELECT uuid FROM workspaces'))).scalars().all() == [workspace_a]
+                assert (
+                    await uow.execute(
+                        text('SELECT uuid FROM workspaces WHERE uuid = :workspace_uuid'),
+                        {'workspace_uuid': workspace_b},
+                    )
+                ).all() == []
+
+            with pytest.raises(sa.exc.DBAPIError):
+                async with TenantUnitOfWork(runtime_engine, workspace_a) as uow:
+                    await uow.execute(
+                        text(
+                            'INSERT INTO workspace_metadata (workspace_uuid, key, value) '
+                            "VALUES (:workspace_uuid, 'cross-scope', 'rejected')"
+                        ),
+                        {'workspace_uuid': workspace_b},
+                    )
+
+            async with TenantUnitOfWork(runtime_engine, workspace_a) as uow:
+                assert (await uow.execute(text('SELECT value FROM workspace_metadata'))).scalars().all() == [
+                    'workspace-a'
+                ]
+            async with TenantUnitOfWork(runtime_engine, workspace_b) as uow:
+                assert (await uow.execute(text('SELECT value FROM workspace_metadata'))).scalars().all() == [
+                    'workspace-b'
+                ]
+            async with runtime_engine.connect() as conn:
+                setting = await conn.scalar(text("SELECT current_setting('langbot.workspace_uuid', true)"))
+                assert setting in (None, '')
+                assert await conn.scalar(text('SELECT COUNT(*) FROM workspace_metadata')) == 0
+
+            with pytest.raises(RuntimeError, match='force rollback'):
+                async with TenantUnitOfWork(runtime_engine, workspace_a) as uow:
+                    await uow.execute(
+                        text(
+                            'INSERT INTO workspace_metadata (workspace_uuid, key, value) '
+                            "VALUES (:workspace_uuid, 'rolled-back', 'no')"
+                        ),
+                        {'workspace_uuid': workspace_a},
+                    )
+                    raise RuntimeError('force rollback')
+            async with TenantUnitOfWork(runtime_engine, workspace_a) as uow:
+                assert (
+                    await uow.session.scalar(text("SELECT COUNT(*) FROM workspace_metadata WHERE key = 'rolled-back'"))
+                    == 0
+                )
+            async with runtime_engine.connect() as conn:
+                setting = await conn.scalar(text("SELECT current_setting('langbot.workspace_uuid', true)"))
+                assert setting in (None, '')
+
+            cloud_manager = PersistenceManager(
+                _application_for_postgres_url(role_url(runtime_role), 'postgres-cloud-runtime-test'),
+                mode=PersistenceMode.CLOUD_RUNTIME,
+            )
+            cloud_manager.create_tables = AsyncMock(side_effect=AssertionError('Cloud runtime attempted create_all'))
+            cloud_manager._run_alembic_migrations = AsyncMock(
+                side_effect=AssertionError('Cloud runtime attempted an Alembic upgrade')
+            )
+            managers.append(cloud_manager)
+            await cloud_manager.initialize()
+            cloud_manager.create_tables.assert_not_awaited()
+            cloud_manager._run_alembic_migrations.assert_not_awaited()
+
+            superuser_manager = PersistenceManager(
+                _application_for_postgres_url(postgres_url, 'postgres-superuser-runtime-test'),
+                mode=PersistenceMode.CLOUD_RUNTIME,
+            )
+            managers.append(superuser_manager)
+            with pytest.raises(RuntimeError, match='must not be a superuser'):
+                await superuser_manager.initialize()
+
+            await create_role(bypass_role, bypass_rls=True)
+            bypass_manager = PersistenceManager(
+                _application_for_postgres_url(role_url(bypass_role), 'postgres-bypass-runtime-test'),
+                mode=PersistenceMode.CLOUD_RUNTIME,
+            )
+            managers.append(bypass_manager)
+            with pytest.raises(RuntimeError, match='must not have BYPASSRLS'):
+                await bypass_manager.initialize()
+
+            await create_role(owner_role)
+            async with postgres_engine.connect() as conn:
+                await conn.execute(text(f'ALTER TABLE workspace_metadata OWNER TO {quote(owner_role)}'))
+            owner_changed = True
+            owner_manager = PersistenceManager(
+                _application_for_postgres_url(role_url(owner_role), 'postgres-owner-runtime-test'),
+                mode=PersistenceMode.CLOUD_RUNTIME,
+            )
+            managers.append(owner_manager)
+            with pytest.raises(RuntimeError, match='must not own tenant tables'):
+                await owner_manager.initialize()
+        finally:
+            if runtime_engine is not None:
+                await runtime_engine.dispose()
+            for manager in reversed(managers):
+                await _dispose_manager(manager)
+
+            async with postgres_engine.connect() as conn:
+                if owner_changed:
+                    await conn.execute(text(f'ALTER TABLE workspace_metadata OWNER TO {quote(admin_user)}'))
+                for role_name in reversed(created_roles):
+                    await conn.execute(text(f'DROP OWNED BY {quote(role_name)}'))
+                    await conn.execute(text(f'DROP ROLE {quote(role_name)}'))

tests/integration/persistence/test_sqlite_migration_backup.py

@@ -47,7 +47,7 @@ async def test_tenancy_migrations_retain_verified_boundary_backups(tmp_path):
 
         await _manager(engine)._run_alembic_migrations()
 
-        assert await alembic_runner.get_alembic_current(engine) == '0010_scope_resources'
+        assert await alembic_runner.get_alembic_current(engine) == alembic_runner.get_alembic_head()
         payloads = _manifest_payloads(tmp_path / 'migration-backups')
         assert len(payloads) == 2
         assert {
@@ -102,6 +102,6 @@ async def test_failed_tenancy_migration_restores_backup_and_revision(
 
         monkeypatch.setattr(alembic_runner, 'run_alembic_upgrade', real_upgrade)
         await _manager(engine)._run_alembic_migrations()
-        assert await alembic_runner.get_alembic_current(engine) == '0010_scope_resources'
+        assert await alembic_runner.get_alembic_current(engine) == alembic_runner.get_alembic_head()
     finally:
         await engine.dispose()

tests/integration/persistence/test_workspace_migration.py

@@ -13,6 +13,7 @@ from langbot.pkg.entity.persistence.base import Base
 from langbot.pkg.entity.persistence.user import User
 from langbot.pkg.persistence.mgr import PersistenceManager
 from langbot.pkg.persistence.alembic_runner import (
+    get_alembic_head,
     get_alembic_current,
     run_alembic_downgrade,
     run_alembic_stamp,
@@ -126,7 +127,7 @@ async def test_legacy_instance_gets_stable_accounts_and_default_workspace(legacy
         assert execution_state['state'] == 'active'
         assert execution_state['write_fenced'] in (False, 0)
 
-    assert await get_alembic_current(legacy_engine) == '0010_scope_resources'
+    assert await get_alembic_current(legacy_engine) == get_alembic_head()
 
 
 async def test_workspace_upgrade_is_idempotent_and_preserves_identifiers(legacy_engine):

tests/unit_tests/api/http/test_entitlement_context.py

@@ -0,0 +1,78 @@
+from __future__ import annotations
+
+from types import SimpleNamespace
+from unittest.mock import AsyncMock
+
+import pytest
+import quart
+
+from langbot.pkg.api.http.context import (
+    ExecutionContext,
+    PrincipalContext,
+    PrincipalType,
+    RequestContext,
+    WorkspaceContext,
+)
+from langbot.pkg.api.http.controller.group import RouterGroup
+from langbot.pkg.cloud.entitlements import EntitlementSnapshot, EntitlementUnavailableError
+from langbot.pkg.cloud.entitlements import EntitlementResolver
+
+
+class _Group(RouterGroup):
+    async def initialize(self) -> None:
+        return None
+
+
+def _router(deployment) -> _Group:
+    provider = getattr(deployment, 'entitlement_provider', None)
+    resolver = EntitlementResolver('instance-a', provider) if provider is not None else None
+    ap = SimpleNamespace(deployment=deployment, entitlement_resolver=resolver)
+    return _Group(ap, quart.Quart(__name__))
+
+
+@pytest.mark.asyncio
+async def test_cloud_request_resolves_verified_entitlement_revision():
+    snapshot = EntitlementSnapshot(
+        instance_uuid='instance-a',
+        workspace_uuid='workspace-a',
+        entitlement_revision=9,
+        status='active',
+        not_before=1,
+        expires_at=4_000_000_000,
+        features={},
+        limits={},
+    )
+    provider = SimpleNamespace(get_workspace_entitlement=AsyncMock(return_value=snapshot))
+    router = _router(SimpleNamespace(multi_workspace_enabled=True, entitlement_provider=provider))
+
+    revision = await router._resolve_entitlement_revision('instance-a', 'workspace-a')
+
+    assert revision == 9
+    provider.get_workspace_entitlement.assert_awaited_once_with('workspace-a')
+
+
+@pytest.mark.asyncio
+async def test_cloud_request_fails_closed_without_entitlement_provider():
+    router = _router(SimpleNamespace(multi_workspace_enabled=True, entitlement_provider=None))
+
+    with pytest.raises(EntitlementUnavailableError):
+        await router._resolve_entitlement_revision('instance-a', 'workspace-a')
+
+
+def test_execution_context_preserves_entitlement_revision():
+    request = RequestContext(
+        instance_uuid='instance-a',
+        placement_generation=1,
+        request_id='request-a',
+        auth_type='user-token',
+        principal=PrincipalContext(PrincipalType.ACCOUNT, account_uuid='account-a'),
+        workspace=WorkspaceContext(
+            workspace_uuid='workspace-a',
+            membership_uuid='membership-a',
+            role='owner',
+            permissions=frozenset(),
+        ),
+        entitlement_revision=11,
+    )
+
+    assert ExecutionContext.from_request(request).entitlement_revision == 11

tests/unit_tests/api/service/test_mcp_service.py

@@ -29,6 +29,7 @@ from langbot.pkg.api.http.context import (
 )
 from langbot.pkg.api.http.service.mcp import MCPService, redact_mcp_secrets, restore_mcp_secret_placeholders
 from langbot.pkg.entity.persistence.mcp import MCPServer
+from langbot.pkg.provider.tools.loaders.mcp_policy import MCPStdioDisabledError
 from langbot.pkg.workspace.errors import WorkspaceNotFoundError
 
 
@@ -351,6 +352,27 @@ class TestMCPServiceGetMCPServers:
 class TestMCPServiceCreateMCPServer:
     """Tests for create_mcp_server method."""
 
+    async def test_create_stdio_rejected_by_independent_instance_gate(self):
+        ap = SimpleNamespace(
+            instance_config=SimpleNamespace(
+                data={
+                    'mcp': {'stdio': {'enabled': False}},
+                    'system': {'limitation': {'max_extensions': -1}},
+                }
+            ),
+            persistence_mgr=SimpleNamespace(execute_async=AsyncMock()),
+            tool_mgr=None,
+        )
+        service = _service(ap)
+
+        with pytest.raises(MCPStdioDisabledError, match='disabled by instance policy'):
+            await service.create_mcp_server(
+                _CONTEXT,
+                {'name': 'local', 'mode': 'stdio', 'enable': True, 'extra_args': {}},
+            )
+
+        ap.persistence_mgr.execute_async.assert_not_awaited()
+
     async def test_create_mcp_server_max_extensions_reached_raises(self):
         """Raises ValueError when max_extensions limit reached."""
         # Setup
@@ -887,6 +909,24 @@ class TestMCPServiceDeleteMCPServer:
 class TestMCPServiceTestMCPServer:
     """Tests for test_mcp_server method."""
 
+    async def test_transient_stdio_test_rejected_by_instance_gate(self):
+        ap = SimpleNamespace(
+            instance_config=SimpleNamespace(data={'mcp': {'stdio': {'enabled': False}}}),
+            tool_mgr=SimpleNamespace(mcp_tool_loader=SimpleNamespace(load_mcp_server=AsyncMock())),
+            task_mgr=SimpleNamespace(create_user_task=Mock()),
+        )
+        service = _service(ap)
+
+        with pytest.raises(MCPStdioDisabledError, match='disabled by instance policy'):
+            await service.test_mcp_server(
+                _CONTEXT,
+                '_',
+                {'name': 'local', 'mode': 'stdio', 'enable': True, 'extra_args': {}},
+            )
+
+        ap.tool_mgr.mcp_tool_loader.load_mcp_server.assert_not_awaited()
+        ap.task_mgr.create_user_task.assert_not_called()
+
     async def test_test_mcp_server_existing_server(self):
         """Tests existing MCP server connection."""
         # Setup

tests/unit_tests/cloud/test_bootstrap.py

@@ -0,0 +1,136 @@
+from __future__ import annotations
+
+from types import SimpleNamespace
+
+import pytest
+
+from langbot.pkg.cloud.bootstrap import (
+    CloudBootstrapError,
+    OpenSourceDeployment,
+    VerifiedCloudDeployment,
+    resolve_deployment,
+)
+from langbot.pkg.cloud.entitlements import EntitlementSnapshot
+
+
+pytestmark = pytest.mark.asyncio
+
+
+class _Entitlements:
+    async def get_workspace_entitlement(self, workspace_uuid: str) -> EntitlementSnapshot:
+        return EntitlementSnapshot(
+            instance_uuid='instance-a',
+            workspace_uuid=workspace_uuid,
+            entitlement_revision=1,
+            status='active',
+            not_before=1,
+            expires_at=4_000_000_000,
+            features={'managed_sandbox': True},
+            limits={'managed_sandbox_sessions': 1},
+        )
+
+
+class _Provider:
+    def bootstrap(self, *, instance_uuid: str, instance_config: dict):
+        del instance_config
+        return VerifiedCloudDeployment(
+            instance_uuid=instance_uuid,
+            manifest_jti='manifest-a',
+            manifest_generation=3,
+            expires_at=4_000_000_000,
+            release='cloud-v2',
+            capabilities=frozenset({'multi_workspace_v2'}),
+            tenant_isolation_version=2,
+            entitlement_provider=_Entitlements(),
+            verification_key_id='root-2026',
+        )
+
+
+class _EntryPoint:
+    def __init__(self, value):
+        self.value = value
+
+    def load(self):
+        return self.value
+
+
+class _EntryPoints(list):
+    def select(self, *, group: str):
+        return self if group == 'langbot.cloud_bootstrap' else []
+
+
+def _cloud_config() -> dict:
+    return {
+        'database': {'use': 'postgresql'},
+        'vdb': {'use': 'pgvector'},
+        'mcp': {'stdio': {'enabled': False}},
+        # Proves mutable product metadata does not participate in selection.
+        'system': {'edition': 'community'},
+    }
+
+
+async def test_no_closed_entry_point_selects_oss_singleton_even_if_edition_says_cloud():
+    deployment = await resolve_deployment(
+        instance_uuid='instance-a',
+        instance_config={'system': {'edition': 'cloud'}},
+        entry_points=lambda: _EntryPoints(),
+    )
+
+    assert isinstance(deployment, OpenSourceDeployment)
+    assert deployment.multi_workspace_enabled is False
+
+
+async def test_verified_closed_entry_point_activates_cloud_policy():
+    deployment = await resolve_deployment(
+        instance_uuid='instance-a',
+        instance_config=_cloud_config(),
+        entry_points=lambda: _EntryPoints([_EntryPoint(_Provider)]),
+        now=1_000,
+    )
+
+    assert isinstance(deployment, VerifiedCloudDeployment)
+    assert deployment.multi_workspace_enabled is True
+    assert deployment.persistence_mode == 'cloud_runtime'
+
+
+@pytest.mark.parametrize(
+    ('field', 'value', 'message'),
+    [
+        ('database', {'use': 'sqlite'}, 'database.use=postgresql'),
+        ('vdb', {'use': 'chroma'}, 'vdb.use=pgvector'),
+        ('mcp', {'stdio': {'enabled': True}}, 'mcp.stdio.enabled=false'),
+    ],
+)
+async def test_cloud_runtime_config_is_fail_closed(field, value, message):
+    config = _cloud_config()
+    config[field] = value
+
+    with pytest.raises(CloudBootstrapError, match=message):
+        await resolve_deployment(
+            instance_uuid='instance-a',
+            instance_config=config,
+            entry_points=lambda: _EntryPoints([_EntryPoint(_Provider())]),
+            now=1_000,
+        )
+
+
+async def test_invalid_provider_never_falls_back_to_oss():
+    provider = SimpleNamespace(bootstrap=lambda **_: object())
+
+    with pytest.raises(CloudBootstrapError, match='must return VerifiedCloudDeployment'):
+        await resolve_deployment(
+            instance_uuid='instance-a',
+            instance_config=_cloud_config(),
+            entry_points=lambda: _EntryPoints([_EntryPoint(provider)]),
+            now=1_000,
+        )
+
+
+async def test_duplicate_closed_providers_fail_closed():
+    with pytest.raises(CloudBootstrapError, match='Exactly one'):
+        await resolve_deployment(
+            instance_uuid='instance-a',
+            instance_config=_cloud_config(),
+            entry_points=lambda: _EntryPoints([_EntryPoint(_Provider()), _EntryPoint(_Provider())]),
+            now=1_000,
+        )

tests/unit_tests/cloud/test_entitlements.py

@@ -0,0 +1,86 @@
+from __future__ import annotations
+
+import pytest
+from unittest.mock import AsyncMock
+
+from langbot.pkg.cloud.entitlements import EntitlementResolver, EntitlementSnapshot, EntitlementUnavailableError
+
+
+def _snapshot(**overrides) -> EntitlementSnapshot:
+    values = {
+        'instance_uuid': 'instance-a',
+        'workspace_uuid': 'workspace-a',
+        'entitlement_revision': 7,
+        'status': 'active',
+        'not_before': 100,
+        'expires_at': 200,
+        'features': {'managed_sandbox': True, 'mcp_stdio': False},
+        'limits': {'managed_sandbox_sessions': 1},
+    }
+    values.update(overrides)
+    return EntitlementSnapshot(**values)
+
+
+def test_active_snapshot_exposes_only_generic_features_and_limits():
+    snapshot = _snapshot().require_active(
+        instance_uuid='instance-a',
+        workspace_uuid='workspace-a',
+        now=150,
+    )
+
+    snapshot.require_feature('managed_sandbox')
+    assert snapshot.limit('managed_sandbox_sessions') == 1
+    assert 'plan' not in snapshot.model_fields
+
+
+@pytest.mark.parametrize(
+    'snapshot,now',
+    [
+        (_snapshot(status='suspended'), 150),
+        (_snapshot(), 99),
+        (_snapshot(), 200),
+    ],
+)
+def test_inactive_or_expired_snapshot_fails_closed(snapshot, now):
+    with pytest.raises(EntitlementUnavailableError):
+        snapshot.require_active(
+            instance_uuid='instance-a',
+            workspace_uuid='workspace-a',
+            now=now,
+        )
+
+
+def test_scope_mismatch_fails_closed():
+    with pytest.raises(EntitlementUnavailableError, match='scope'):
+        _snapshot().require_active(
+            instance_uuid='instance-a',
+            workspace_uuid='workspace-b',
+            now=150,
+        )
+
+
+@pytest.mark.asyncio
+async def test_resolver_rejects_revision_rollback():
+    provider = AsyncMock()
+    provider.get_workspace_entitlement = AsyncMock(side_effect=[_snapshot(), _snapshot(entitlement_revision=6)])
+    resolver = EntitlementResolver('instance-a', provider)
+
+    await resolver.resolve('workspace-a', now=150)
+    with pytest.raises(EntitlementUnavailableError, match='rolled back'):
+        await resolver.resolve('workspace-a', now=150)
+
+
+@pytest.mark.asyncio
+async def test_resolver_rejects_same_revision_with_different_contents():
+    provider = AsyncMock()
+    provider.get_workspace_entitlement = AsyncMock(
+        side_effect=[
+            _snapshot(),
+            _snapshot(features={'managed_sandbox': False}),
+        ]
+    )
+    resolver = EntitlementResolver('instance-a', provider)
+
+    await resolver.resolve('workspace-a', now=150)
+    with pytest.raises(EntitlementUnavailableError, match='conflicting contents'):
+        await resolver.resolve('workspace-a', now=150)

tests/unit_tests/core/test_load_config.py

@@ -259,6 +259,60 @@ class TestApplyEnvOverridesToConfig:
         assert result['system']['enable'] is False
         assert result['concurrency']['pipeline'] == 10
 
+    def test_plugin_worker_and_stdio_policy_native_env_overrides(self):
+        load_config = get_load_config_module()
+        cfg = {
+            'plugin': {
+                'worker': {
+                    'max_cpus': 1.0,
+                    'max_memory_mb': 512,
+                    'max_pids': 128,
+                    'max_open_files': 256,
+                    'max_file_size_mb': 512,
+                }
+            },
+            'mcp': {'stdio': {'enabled': True}},
+        }
+        env = {
+            'PLUGIN__WORKER__MAX_CPUS': '2.5',
+            'PLUGIN__WORKER__MAX_MEMORY_MB': '1024',
+            'PLUGIN__WORKER__MAX_PIDS': '64',
+            'PLUGIN__WORKER__MAX_OPEN_FILES': '128',
+            'PLUGIN__WORKER__MAX_FILE_SIZE_MB': '256',
+            'MCP__STDIO__ENABLED': 'false',
+        }
+
+        with patch.dict(os.environ, env, clear=True):
+            result = load_config._apply_env_overrides_to_config(cfg)
+
+        assert result['plugin']['worker'] == {
+            'max_cpus': 2.5,
+            'max_memory_mb': 1024,
+            'max_pids': 64,
+            'max_open_files': 128,
+            'max_file_size_mb': 256,
+        }
+        assert result['mcp']['stdio']['enabled'] is False
+
+    def test_runtime_policy_defaults_preserve_env_types_for_upgraded_config(self):
+        load_config = get_load_config_module()
+        cfg = {'plugin': {'enable': True}}
+
+        completed = load_config._complete_runtime_policy_defaults(cfg)
+        with patch.dict(
+            os.environ,
+            {
+                'PLUGIN__WORKER__MAX_MEMORY_MB': '768',
+                'MCP__STDIO__ENABLED': 'false',
+            },
+            clear=True,
+        ):
+            result = load_config._apply_env_overrides_to_config(completed)
+
+        assert result['plugin']['worker']['max_memory_mb'] == 768
+        assert isinstance(result['plugin']['worker']['max_memory_mb'], int)
+        assert result['mcp']['stdio']['enabled'] is False
+
     def test_webhook_prefix_override(self):
         """Test overriding webhook_prefix via environment variable."""
         load_config = get_load_config_module()

tests/unit_tests/persistence/test_tenant_uow.py

@@ -0,0 +1,63 @@
+from __future__ import annotations
+
+import pytest
+import sqlalchemy as sa
+from sqlalchemy.ext.asyncio import create_async_engine
+
+from langbot.pkg.persistence.mgr import PersistenceManager, PersistenceMode
+from langbot.pkg.persistence.tenant_uow import TenantUnitOfWork
+
+
+pytestmark = pytest.mark.asyncio
+
+
+async def test_sqlite_tenant_uow_commits_and_rolls_back() -> None:
+    engine = create_async_engine('sqlite+aiosqlite:///:memory:')
+    table = sa.Table(
+        'uow_rows',
+        sa.MetaData(),
+        sa.Column('id', sa.Integer, primary_key=True),
+        sa.Column('workspace_uuid', sa.String(36), nullable=False),
+    )
+    try:
+        async with engine.begin() as conn:
+            await conn.run_sync(table.metadata.create_all)
+
+        async with TenantUnitOfWork(engine, 'workspace-a') as uow:
+            await uow.execute(sa.insert(table).values(id=1, workspace_uuid='workspace-a'))
+
+        with pytest.raises(RuntimeError, match='roll back'):
+            async with TenantUnitOfWork(engine, 'workspace-a') as uow:
+                await uow.execute(sa.insert(table).values(id=2, workspace_uuid='workspace-a'))
+                raise RuntimeError('roll back this transaction')
+
+        async with engine.connect() as conn:
+            rows = (await conn.execute(sa.select(table.c.id).order_by(table.c.id))).scalars().all()
+        assert rows == [1]
+    finally:
+        await engine.dispose()
+
+
+async def test_tenant_uow_is_single_use_and_requires_an_active_scope() -> None:
+    engine = create_async_engine('sqlite+aiosqlite:///:memory:')
+    uow = TenantUnitOfWork(engine, 'workspace-a')
+    try:
+        with pytest.raises(RuntimeError, match='not active'):
+            _ = uow.session
+
+        async with uow:
+            assert uow.session.in_transaction()
+
+        with pytest.raises(RuntimeError, match='cannot be reused'):
+            async with uow:
+                pass
+    finally:
+        await engine.dispose()
+
+
+def test_persistence_mode_must_be_a_trusted_enum() -> None:
+    with pytest.raises(TypeError, match='trusted PersistenceMode'):
+        PersistenceManager(object(), mode='cloud_runtime')  # type: ignore[arg-type]
+
+    manager = PersistenceManager(object(), mode=PersistenceMode.CLOUD_RUNTIME)
+    assert manager.mode is PersistenceMode.CLOUD_RUNTIME

tests/unit_tests/provider/test_mcp_box_integration.py

@@ -154,6 +154,7 @@ def mcp_module():
 def _make_ap():
     ap = Mock()
     ap.logger = Mock()
+    ap.instance_config = SimpleNamespace(data={'mcp': {'stdio': {'enabled': True}}})
     ap.workspace_service = Mock()
     ap.workspace_service.get_execution_binding = AsyncMock(
         return_value=SimpleNamespace(
@@ -791,6 +792,31 @@ class TestBoxConfigParsing:
         assert s.box_config.host_path_mode == 'ro'
 
 
+@pytest.mark.asyncio
+async def test_stdio_instance_gate_runs_before_box_transport(mcp_module):
+    ap = _make_ap()
+    ap.instance_config.data['mcp']['stdio']['enabled'] = False
+    ap.box_service.available = True
+    session = _make_session(
+        mcp_module,
+        {
+            'name': 'blocked',
+            'uuid': 'blocked-uuid',
+            'mode': 'stdio',
+            'command': 'python',
+            'args': [],
+            'env': {},
+        },
+        ap=ap,
+    )
+    session._box_stdio_runtime.initialize = AsyncMock()
+
+    with pytest.raises(RuntimeError, match='disabled by instance policy'):
+        await session._init_stdio_python_server()
+
+    session._box_stdio_runtime.initialize.assert_not_awaited()
+
+
 @pytest.mark.asyncio
 async def test_init_box_stdio_server_stages_host_path_in_shared_workspace(mcp_module, tmp_path):
     mcp_stdio_module = sys.modules['langbot.pkg.provider.tools.loaders.mcp_stdio']

tests/unit_tests/provider/test_mcp_stdio_policy.py

@@ -0,0 +1,70 @@
+from __future__ import annotations
+
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, Mock
+
+import pytest
+
+from langbot.pkg.provider.tools.loaders.mcp_policy import (
+    MCPStdioDisabledError,
+    require_stdio_mcp_enabled,
+    stdio_mcp_enabled,
+)
+from langbot.pkg.provider.tools.loaders.mcp import MCPLoader
+
+
+def _app(config: dict) -> SimpleNamespace:
+    return SimpleNamespace(instance_config=SimpleNamespace(data=config))
+
+
+def test_oss_default_remains_enabled_when_key_is_absent():
+    assert stdio_mcp_enabled(_app({})) is True
+
+
+@pytest.mark.parametrize(
+    'value',
+    [False, 'false', 0, None, {}, []],
+)
+def test_disabled_or_invalid_values_fail_closed(value):
+    ap = _app({'mcp': {'stdio': {'enabled': value}}})
+
+    assert stdio_mcp_enabled(ap) is False
+    with pytest.raises(MCPStdioDisabledError, match='disabled by instance policy'):
+        require_stdio_mcp_enabled(ap, {'mode': 'stdio'})
+
+
+def test_remote_transport_is_independent_of_stdio_gate():
+    ap = _app({'mcp': {'stdio': {'enabled': False}}})
+
+    require_stdio_mcp_enabled(ap, {'mode': 'remote'})
+
+
+@pytest.mark.asyncio
+async def test_bootstrap_retains_but_does_not_launch_disabled_stdio_rows():
+    server = SimpleNamespace(uuid='server-a', workspace_uuid='workspace-a')
+    result = Mock()
+    result.all.return_value = [server]
+    ap = _app({'mcp': {'stdio': {'enabled': False}}})
+    ap.logger = Mock()
+    ap.persistence_mgr = SimpleNamespace(
+        execute_async=AsyncMock(return_value=result),
+        serialize_model=Mock(
+            return_value={
+                'uuid': 'server-a',
+                'workspace_uuid': 'workspace-a',
+                'name': 'local',
+                'mode': 'stdio',
+                'enable': True,
+                'extra_args': {},
+            }
+        ),
+    )
+    ap.workspace_service = SimpleNamespace(get_execution_binding=AsyncMock())
+    loader = MCPLoader(ap)
+    loader.host_mcp_server = AsyncMock()
+
+    await loader.load_mcp_servers_from_db()
+
+    loader.host_mcp_server.assert_not_awaited()
+    ap.workspace_service.get_execution_binding.assert_not_awaited()
+    assert loader.sessions == {}

web/src/app/home/mcp/components/mcp-form/MCPForm.tsx

@@ -56,6 +56,7 @@ import {
 import { CustomApiError } from '@/app/infra/entities/common';
 import { BoxUnavailableNotice } from '@/app/home/components/BoxUnavailableNotice';
 import { useBoxStatus } from '@/app/infra/hooks/useBoxStatus';
+import { useMCPStdioPolicy } from '@/app/infra/hooks/useMCPStdioPolicy';
 
 function StatusDisplay({
   testing,
@@ -560,11 +561,15 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
     hint: boxHint,
     reason: boxReason,
   } = useBoxStatus();
+  const { enabled: mcpStdioEnabled } = useMCPStdioPolicy();
   // stdio mode requires the Box sandbox at runtime. If the user picks
   // stdio while Box is disabled / unreachable, the server would refuse
   // to start anyway — block creation upfront so they aren't surprised
   // by an immediate "Connection failed" on the detail page.
-  const stdioBlockedByBox = watchMode === 'stdio' && !boxAvailable;
+  const stdioBlockedByPolicy = watchMode === 'stdio' && !mcpStdioEnabled;
+  const stdioBlockedByBox =
+    watchMode === 'stdio' && mcpStdioEnabled && !boxAvailable;
+  const stdioBlocked = stdioBlockedByPolicy || stdioBlockedByBox;
 
   const { isDirty } = form.formState;
   useEffect(() => {
@@ -572,8 +577,8 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
   }, [isDirty, onDirtyChange]);
 
   useEffect(() => {
-    onSaveBlockedChange?.(stdioBlockedByBox);
-  }, [stdioBlockedByBox, onSaveBlockedChange]);
+    onSaveBlockedChange?.(stdioBlocked);
+  }, [stdioBlocked, onSaveBlockedChange]);
 
   useEffect(() => {
     onTestingChange?.(mcpTesting);
@@ -589,10 +594,9 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
       testMcp: () => testMcp(),
       isTesting: mcpTesting,
     }),
-    // testMcp now reads everything via form.getValues(), so it does not need
-    // the latest stdioArgs/extraArgs closure — but keep mcpTesting so the
-    // exposed isTesting flag stays accurate.
-    [mcpTesting],
+    // Form values are read through form.getValues(); policy and runtime health
+    // remain closure values and must refresh the imperative handler.
+    [mcpTesting, mcpStdioEnabled, boxAvailable],
   );
 
   useEffect(() => {
@@ -747,6 +751,10 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
   async function handleFormSubmit(value: z.infer<typeof formSchema>) {
     // Belt-and-suspenders: even though the Save button is disabled when
     // stdio is unselectable, intercept programmatic submits too.
+    if (value.mode === 'stdio' && !mcpStdioEnabled) {
+      toast.error(t('mcp.stdioDisabledByPolicy'));
+      return;
+    }
     if (value.mode === 'stdio' && !boxAvailable) {
       toast.error(t('mcp.stdioBlockedByBoxToast'));
       return;
@@ -814,6 +822,16 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
 
     try {
       const mode = form.getValues('mode');
+      if (mode === 'stdio' && !mcpStdioEnabled) {
+        toast.error(t('mcp.stdioDisabledByPolicy'));
+        setMcpTesting(false);
+        return;
+      }
+      if (mode === 'stdio' && !boxAvailable) {
+        toast.error(t('mcp.stdioBlockedByBoxToast'));
+        setMcpTesting(false);
+        return;
+      }
       // Read every field via form.getValues() rather than the captured
       // `stdioArgs` / `extraArgs` state. testMcp() is invoked through an
       // imperative handle (formRef.current.testMcp()) whose closure is only
@@ -1020,13 +1038,20 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
                 </FormControl>
                 <SelectContent>
                   <SelectItem value="remote">{t('mcp.remote')}</SelectItem>
-                  <SelectItem value="stdio" disabled={!boxAvailable}>
+                  <SelectItem
+                    value="stdio"
+                    disabled={!mcpStdioEnabled || !boxAvailable}
+                  >
                     {t('mcp.local')}
-                    {!boxAvailable && (
+                    {!mcpStdioEnabled ? (
+                      <span className="ml-2 text-xs text-muted-foreground">
+                        ({t('mcp.disabledByPolicy')})
+                      </span>
+                    ) : !boxAvailable ? (
                       <span className="ml-2 text-xs text-muted-foreground">
                         ({t('mcp.boxRequired')})
                       </span>
-                    )}
+                    ) : null}
                   </SelectItem>
                 </SelectContent>
               </Select>
@@ -1035,6 +1060,14 @@ const MCPForm = forwardRef<MCPFormHandle, MCPFormProps>(function MCPForm(
                   ? t('mcp.localModeDescription')
                   : t('mcp.remoteModeDescription')}
               </FormDescription>
+              {stdioBlockedByPolicy && (
+                <div
+                  role="alert"
+                  className="mt-2 rounded-md border border-amber-500/40 bg-amber-500/10 p-3 text-sm text-amber-800 dark:text-amber-200"
+                >
+                  {t('mcp.stdioDisabledByPolicy')}
+                </div>
+              )}
               {stdioBlockedByBox && (
                 <BoxUnavailableNotice
                   hint={boxHint}

web/src/app/infra/entities/api/index.ts

@@ -346,6 +346,8 @@ export interface ApiRespSystemInfo {
   debug: boolean;
   version: string;
   edition: string;
+  /** Independent instance-level gate for local stdio MCP transports. */
+  mcp_stdio_enabled: boolean;
   cloud_service_url: string;
   enable_marketplace: boolean;
   allow_modify_login_info: boolean;

web/src/app/infra/hooks/useMCPStdioPolicy.ts

@@ -0,0 +1,32 @@
+import { useCallback, useEffect, useState } from 'react';
+
+import { httpClient } from '@/app/infra/http/HttpClient';
+
+/**
+ * Load the instance-level stdio MCP gate independently of Box health.
+ *
+ * The hook fails closed while loading or when System Info is unavailable.
+ * This is only a WebUI guard; the backend loader enforces the same gate at
+ * the final transport boundary.
+ */
+export function useMCPStdioPolicy() {
+  const [enabled, setEnabled] = useState(false);
+  const [loading, setLoading] = useState(true);
+
+  const refresh = useCallback(async () => {
+    try {
+      const info = await httpClient.getSystemInfo();
+      setEnabled(info.mcp_stdio_enabled === true);
+    } catch {
+      setEnabled(false);
+    } finally {
+      setLoading(false);
+    }
+  }, []);
+
+  useEffect(() => {
+    void refresh();
+  }, [refresh]);
+
+  return { enabled, loading, refresh };
+}

web/src/app/infra/http/index.ts

@@ -25,6 +25,7 @@ export const systemInfo: ApiRespSystemInfo = {
   debug: false,
   version: '',
   edition: 'community',
+  mcp_stdio_enabled: false,
   enable_marketplace: true,
   cloud_service_url: '',
   allow_modify_login_info: true,

web/src/i18n/locales/en-US.ts

@@ -820,6 +820,9 @@ const enUS = {
     boxStdioRefusedSuggestion:
       'Enable Box (box.enabled = true) and ensure the runtime is healthy, or switch this server to http/sse mode.',
     boxRequired: 'requires Box',
+    disabledByPolicy: 'disabled by policy',
+    stdioDisabledByPolicy:
+      'Stdio MCP is disabled for this deployment. Use a remote MCP server instead.',
     stdioBlockedByBoxToast:
       'Stdio MCP cannot be saved while the Box sandbox is disabled or unreachable. Enable Box or pick http/sse.',
     toolsFound: 'tools',

web/src/i18n/locales/es-ES.ts

@@ -833,6 +833,9 @@ const esES = {
     boxStdioRefusedSuggestion:
       'Active Box (box.enabled = true) y asegúrese de que el runtime está conectado, o cambie este servidor a modo http/sse.',
     boxRequired: 'requiere Box',
+    disabledByPolicy: 'desactivado por la política',
+    stdioDisabledByPolicy:
+      'Stdio MCP está deshabilitado en este despliegue. Use un servidor MCP remoto.',
     stdioBlockedByBoxToast:
       'No se puede guardar el MCP en modo stdio mientras el sandbox de Box está desactivado o no disponible. Active Box o seleccione modo http/sse.',
     toolsFound: 'herramientas',

web/src/i18n/locales/ja-JP.ts

@@ -826,6 +826,9 @@ const jaJP = {
     boxStdioRefusedSuggestion:
       'Box を有効化（box.enabled = true）してランタイムの接続を確認するか、このサーバーを http/sse モードに切り替えてください。',
     boxRequired: 'Box が必要',
+    disabledByPolicy: 'ポリシーにより無効',
+    stdioDisabledByPolicy:
+      'このデプロイでは Stdio MCP が無効です。リモート MCP サーバーを使用してください。',
     stdioBlockedByBoxToast:
       'Box サンドボックスが無効または利用できないため、stdio モードの MCP は保存できません。Box を有効化するか、http/sse モードに切り替えてください。',
     toolsFound: '個のツール',

web/src/i18n/locales/ru-RU.ts

@@ -830,6 +830,9 @@ const ruRU = {
     boxStdioRefusedSuggestion:
       'Включите Box (box.enabled = true) и убедитесь, что среда работает, либо переключите этот сервер в режим http/sse.',
     boxRequired: 'требуется Box',
+    disabledByPolicy: 'отключено политикой',
+    stdioDisabledByPolicy:
+      'Stdio MCP отключён в этом развёртывании. Используйте удалённый MCP-сервер.',
     stdioBlockedByBoxToast:
       'Сохранить MCP в режиме stdio нельзя: песочница Box отключена или недоступна. Включите Box либо выберите режим http/sse.',
     toolsFound: 'инструментов',

web/src/i18n/locales/th-TH.ts

@@ -808,6 +808,9 @@ const thTH = {
     boxStdioRefusedSuggestion:
       'กรุณาเปิดใช้งาน Box (box.enabled = true) และตรวจสอบว่ารันไทม์ทำงานปกติ หรือเปลี่ยน MCP server เป็นโหมด http/sse',
     boxRequired: 'ต้องใช้ Box',
+    disabledByPolicy: 'ถูกปิดใช้งานโดยนโยบาย',
+    stdioDisabledByPolicy:
+      'การติดตั้งใช้งานนี้ปิด Stdio MCP อยู่ โปรดใช้เซิร์ฟเวอร์ MCP แบบระยะไกล',
     stdioBlockedByBoxToast:
       'ไม่สามารถบันทึก MCP โหมด stdio เนื่องจาก Sandbox Box ถูกปิดใช้งานหรือไม่พร้อมใช้งาน กรุณาเปิดใช้งาน Box หรือเลือกโหมด http/sse',
     toolsFound: 'เครื่องมือ',

web/src/i18n/locales/vi-VN.ts

@@ -823,6 +823,9 @@ const viVN = {
     boxStdioRefusedSuggestion:
       'Hãy bật Box (box.enabled = true) và đảm bảo runtime hoạt động, hoặc chuyển server này sang chế độ http/sse.',
     boxRequired: 'cần Box',
+    disabledByPolicy: 'bị tắt theo chính sách',
+    stdioDisabledByPolicy:
+      'Stdio MCP đã bị tắt trong bản triển khai này. Hãy dùng máy chủ MCP từ xa.',
     stdioBlockedByBoxToast:
       'Không thể lưu MCP ở chế độ stdio khi Sandbox Box bị tắt hoặc không khả dụng. Hãy bật Box hoặc chọn chế độ http/sse.',
     toolsFound: 'công cụ',

web/src/i18n/locales/zh-Hans.ts

@@ -786,6 +786,8 @@ const zhHans = {
     boxStdioRefusedSuggestion:
       '请启用 Box（box.enabled = true）并确认运行时连接正常，或将此服务器切换到 http/sse 模式。',
     boxRequired: '需要 Box',
+    disabledByPolicy: '已被策略禁用',
+    stdioDisabledByPolicy: '此部署已禁用 Stdio MCP，请改用远程 MCP 服务器。',
     stdioBlockedByBoxToast:
       'Box 沙箱已禁用或不可用，无法保存 stdio 模式的 MCP。请启用 Box 或改为 http/sse 模式。',
     toolsFound: '个工具',

web/src/i18n/locales/zh-Hant.ts

@@ -784,6 +784,8 @@ const zhHant = {
     boxStdioRefusedSuggestion:
       '請啟用 Box（box.enabled = true）並確認執行時連線正常，或將此伺服器切換到 http/sse 模式。',
     boxRequired: '需要 Box',
+    disabledByPolicy: '已被策略停用',
+    stdioDisabledByPolicy: '此部署已停用 Stdio MCP，請改用遠端 MCP 伺服器。',
     stdioBlockedByBoxToast:
       'Box 沙箱已停用或無法使用，無法儲存 stdio 模式的 MCP。請啟用 Box 或改為 http/sse 模式。',
     toolsFound: '個工具',