fix(cloud): retain launch replay records through clock skew

.github/workflows/deploy-prod.yml

@@ -0,0 +1,78 @@
+name: Build and deploy production
+
+on:
+  push:
+    branches: [deploy/prod]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: langbot-production
+  cancel-in-progress: false
+
+env:
+  CORE_IMAGE: ${{ secrets.DOCKER_USERNAME }}/langbot
+  CLOUD_IMAGE: ${{ secrets.DOCKER_USERNAME }}/langbot-cloud-core
+  SPACE_REF: e1b261dac45e886efc667b1096a4ec493c6a6111
+
+jobs:
+  build-and-deploy:
+    runs-on: ubuntu-latest
+    environment: production
+    steps:
+      - uses: actions/checkout@v4
+      - uses: docker/setup-buildx-action@v3
+      - uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Build exact Core image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          push: true
+          tags: |
+            ${{ env.CORE_IMAGE }}:prod-${{ github.sha }}
+            ${{ env.CORE_IMAGE }}:deploy-prod
+          cache-from: type=gha,scope=core-prod
+          cache-to: type=gha,mode=max,scope=core-prod
+      - name: Checkout production Cloud adapter
+        uses: actions/checkout@v4
+        with:
+          repository: langbot-app/langbot-space
+          ref: ${{ env.SPACE_REF }}
+          token: ${{ secrets.CLA_PAT }}
+          path: .space
+      - name: Build exact Cloud Core image
+        uses: docker/build-push-action@v6
+        with:
+          context: .space
+          file: .space/Dockerfile.cloud
+          push: true
+          build-args: LANGBOT_CORE_IMAGE=${{ env.CORE_IMAGE }}:prod-${{ github.sha }}
+          tags: |
+            ${{ env.CLOUD_IMAGE }}:prod-${{ github.sha }}
+            ${{ env.CLOUD_IMAGE }}:deploy-prod
+          cache-from: type=gha,scope=cloud-core-prod
+          cache-to: type=gha,mode=max,scope=cloud-core-prod
+      - name: Configure SSH
+        env:
+          SSH_KEY: ${{ secrets.JP09_SSH_KEY }}
+          KNOWN_HOSTS: ${{ secrets.JP09_KNOWN_HOSTS }}
+        run: |
+          install -m 700 -d ~/.ssh
+          install -m 600 /dev/null ~/.ssh/id_ed25519
+          printf '%s\n' "$SSH_KEY" > ~/.ssh/id_ed25519
+          printf '%s\n' "$KNOWN_HOSTS" > ~/.ssh/known_hosts
+      - name: Upload release manifest and deploy
+        env:
+          HOST: ${{ secrets.JP09_HOST }}
+          USER: ${{ secrets.JP09_USER }}
+          PORT: ${{ secrets.JP09_PORT }}
+        run: |
+          remote="$USER@$HOST"
+          ssh -p "$PORT" "$remote" 'install -d -m 700 /opt/langbot-cloud-prod'
+          scp -P "$PORT" deploy/prod/docker-compose.yml deploy/prod/deploy.sh "$remote:/opt/langbot-cloud-prod/"
+          ssh -p "$PORT" "$remote" "chmod 700 /opt/langbot-cloud-prod/deploy.sh && /opt/langbot-cloud-prod/deploy.sh prod-${GITHUB_SHA}"

deploy/prod/deploy.sh

@@ -0,0 +1,92 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+cd /opt/langbot-cloud-prod
+TAG=${1:?usage: deploy.sh prod-<40-char-sha>}
+[[ "$TAG" =~ ^prod-[0-9a-f]{40}$ ]] || { echo 'invalid immutable image tag' >&2; exit 2; }
+[[ -s .env ]] || { echo '/opt/langbot-cloud-prod/.env is missing' >&2; exit 3; }
+
+rendered_compose=$(docker compose config)
+grep -Fq 'LANGBOT_SPACE_CONTROL_PLANE_URL: https://space.langbot.app' <<<"$rendered_compose" || {
+  echo 'Cloud control-plane URL must be https://space.langbot.app' >&2
+  exit 4
+}
+grep -Fq 'SPACE__URL: https://space.langbot.app' <<<"$rendered_compose" || {
+  echo 'Cloud user-facing Space URL must be https://space.langbot.app' >&2
+  exit 5
+}
+
+update_env() {
+  local key=$1 value=$2
+  python3 - "$key" "$value" <<'PY'
+from pathlib import Path
+import os
+import sys
+
+path = Path('.env')
+key, value = sys.argv[1:]
+lines = path.read_text().splitlines()
+updated = False
+for index, line in enumerate(lines):
+    if line.startswith(f'{key}='):
+        lines[index] = f'{key}={value}'
+        updated = True
+        break
+if not updated:
+    lines.append(f'{key}={value}')
+temporary = Path('.env.tmp')
+temporary.write_text('\n'.join(lines) + '\n')
+os.chmod(temporary, 0o600)
+temporary.replace(path)
+PY
+}
+update_env LANGBOT_IMAGE_TAG "$TAG"
+set -a
+. ./.env
+set +a
+
+for attempt in 1 2 3 4 5; do
+  if docker compose pull postgres redis migrate plugin-runtime core; then
+    break
+  fi
+  if [ "$attempt" -eq 5 ]; then
+    echo "docker compose pull failed after $attempt attempts" >&2
+    exit 1
+  fi
+  delay=$((attempt * 10))
+  echo "docker compose pull failed (attempt $attempt/5); retrying in ${delay}s" >&2
+  sleep "$delay"
+done
+docker compose up -d postgres redis
+for _ in $(seq 1 60); do
+  if docker compose exec -T postgres pg_isready -U langbot_operator -d langbot >/dev/null 2>&1; then break; fi
+  sleep 2
+done
+docker compose exec -T postgres pg_isready -U langbot_operator -d langbot >/dev/null
+
+docker compose exec -T postgres psql -v ON_ERROR_STOP=1 -U langbot_operator -d langbot \
+  -v runtime_password="$POSTGRES_RUNTIME_PASSWORD" <<'SQL'
+SELECT format('CREATE ROLE langbot_runtime LOGIN PASSWORD %L', :'runtime_password')
+WHERE NOT EXISTS (SELECT 1 FROM pg_roles WHERE rolname = 'langbot_runtime')\gexec
+ALTER ROLE langbot_runtime PASSWORD :'runtime_password';
+GRANT CONNECT ON DATABASE langbot TO langbot_runtime;
+REVOKE CREATE ON SCHEMA public FROM PUBLIC, langbot_runtime;
+REVOKE ALL PRIVILEGES ON ALL TABLES IN SCHEMA public FROM langbot_runtime;
+REVOKE ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA public FROM langbot_runtime;
+ALTER DEFAULT PRIVILEGES FOR ROLE langbot_operator IN SCHEMA public REVOKE ALL ON TABLES FROM langbot_runtime;
+ALTER DEFAULT PRIVILEGES FOR ROLE langbot_operator IN SCHEMA public REVOKE ALL ON SEQUENCES FROM langbot_runtime;
+GRANT USAGE ON SCHEMA public TO langbot_runtime;
+SQL
+
+docker compose --profile tools run --rm migrate
+
+docker compose up -d --remove-orphans plugin-runtime core
+for _ in $(seq 1 90); do
+  if docker compose exec -T core python -c 'import urllib.request; urllib.request.urlopen("http://127.0.0.1:5300/healthz", timeout=3)' >/dev/null 2>&1; then
+    docker compose ps
+    exit 0
+  fi
+  sleep 2
+done
+docker compose logs --tail=200 core plugin-runtime >&2
+exit 1

deploy/prod/docker-compose.yml

@@ -0,0 +1,161 @@
+services:
+  postgres:
+    image: pgvector/pgvector:pg17
+    container_name: langbot-cloud-postgres
+    restart: unless-stopped
+    environment:
+      POSTGRES_DB: langbot
+      POSTGRES_USER: langbot_operator
+      POSTGRES_PASSWORD: ${POSTGRES_OPERATOR_PASSWORD}
+    volumes:
+      - postgres-data:/var/lib/postgresql/data
+    healthcheck:
+      test: [CMD-SHELL, "pg_isready -U langbot_operator -d langbot"]
+      interval: 5s
+      timeout: 5s
+      retries: 30
+    networks: [internal]
+
+  redis:
+    image: redis:7.4-alpine
+    container_name: langbot-cloud-redis
+    restart: unless-stopped
+    command: [redis-server, --appendonly, "yes", --requirepass, "${REDIS_PASSWORD}"]
+    volumes:
+      - redis-data:/data
+    healthcheck:
+      test: [CMD-SHELL, "redis-cli -a \"$${REDIS_PASSWORD}\" ping | grep PONG"]
+      interval: 5s
+      timeout: 5s
+      retries: 20
+    environment:
+      REDIS_PASSWORD: ${REDIS_PASSWORD}
+    networks: [internal]
+
+  migrate:
+    image: rockchin/langbot-cloud-core:${LANGBOT_IMAGE_TAG}
+    profiles: [tools]
+    command: [uv, run, langbot, migrate, --cloud]
+    environment: &core-env
+      TZ: Asia/Shanghai
+      SYSTEM__INSTANCE_ID: ${CLOUD_V2_INSTANCE_UUID}
+      SYSTEM__EDITION: cloud
+      SYSTEM__RECOVERY_KEY: ${SYSTEM_RECOVERY_KEY}
+      SYSTEM__JWT__SECRET: ${JWT_SECRET}
+      SYSTEM__LIMITATION__MAX_BOTS: "2"
+      SYSTEM__LIMITATION__MAX_PIPELINES: "3"
+      SYSTEM__LIMITATION__MAX_EXTENSIONS: "3"
+      SYSTEM__LIMITATION__MAX_KNOWLEDGE_BASES: "2"
+      API__WEBHOOK_PREFIX: https://cloud.langbot.app
+      API__WEBUI_URL: https://cloud.langbot.app
+      WORKSPACE__INVITATIONS__PUBLIC_WEB_URL: https://cloud.langbot.app
+      DATABASE__USE: postgresql
+      DATABASE__POSTGRESQL__URL: postgresql+asyncpg://langbot_runtime:${POSTGRES_RUNTIME_PASSWORD}@postgres:5432/langbot
+      DATABASE__CLOUD_MIGRATION__OPERATOR_DSN_ENV: LANGBOT_CLOUD_MIGRATION_DSN
+      LANGBOT_CLOUD_MIGRATION_DSN: postgresql://langbot_operator:${POSTGRES_OPERATOR_PASSWORD}@postgres:5432/langbot
+      VDB__USE: pgvector
+      VDB__PGVECTOR__USE_BUSINESS_DATABASE: "true"
+      VDB__PGVECTOR__ALLOWED_DIMENSIONS: "384,512,768,1024,1536"
+      PLUGIN__ENABLE: "true"
+      PLUGIN__RUNTIME_WS_URL: ws://plugin-runtime:5400/control/ws
+      PLUGIN__DISPLAY_PLUGIN_DEBUG_URL: wss://cloud.langbot.app/plugin/debug/ws
+      PLUGIN__WORKER__MAX_CPUS: "0.25"
+      PLUGIN__WORKER__MAX_MEMORY_MB: "256"
+      PLUGIN__WORKER__MAX_PIDS: "128"
+      PLUGIN__WORKER__MAX_WORKERS: "16"
+      PLUGIN__WORKER__MAX_TOTAL_CPUS: "4.0"
+      PLUGIN__WORKER__MAX_TOTAL_MEMORY_MB: "4096"
+      PLUGIN__WORKER__REQUIRE_HARD_LIMITS: "true"
+      LANGBOT_PLUGIN_RUNTIME_CONTROL_TOKEN: ${PLUGIN_RUNTIME_CONTROL_TOKEN}
+      # Cloud v2 currently grants no managed Box capability. Keep the shared
+      # runtime deployed but disable Core integration until a hard-quota-capable
+      # backend can satisfy the fail-closed Cloud readiness contract.
+      BOX__ENABLED: "false"
+      BOX__BACKEND: nsjail
+      BOX__RUNTIME__ENDPOINT: ws://box:5410
+      BOX__ADMISSION__REQUIRED: "true"
+      BOX__ADMISSION__LOGICAL_SESSION_ID: global
+      BOX__ADMISSION__REQUIRED_BACKEND: nsjail
+      BOX__ADMISSION__MAX_SESSIONS: "1"
+      BOX__ADMISSION__MAX_MANAGED_PROCESSES: "0"
+      BOX__ADMISSION__CPUS: "0.25"
+      BOX__ADMISSION__MEMORY_MB: "256"
+      BOX__ADMISSION__WORKSPACE_QUOTA_MB: "256"
+      BOX__LOCAL__HOST_ROOT: /app/data/box
+      BOX__LOCAL__DEFAULT_WORKSPACE: /app/data/box
+      BOX__LOCAL__ALLOWED_MOUNT_ROOTS: /app/data/box
+      LANGBOT_BOX_CONTROL_TOKEN: ${BOX_CONTROL_TOKEN}
+      MCP__STDIO__ENABLED: "false"
+      LANGBOT_SPACE_CONTROL_PLANE_URL: https://space.langbot.app
+      LANGBOT_SPACE_CONTROL_PLANE_TOKEN: ${CLOUD_V2_CONTROL_PLANE_TOKEN}
+      LANGBOT_SPACE_CONTROL_PLANE_PUBLIC_KEY: ${CLOUD_V2_MANIFEST_PUBLIC_KEY}
+      LANGBOT_SPACE_CONTROL_PLANE_KEY_ID: ${CLOUD_V2_MANIFEST_KEY_ID}
+      SPACE__URL: https://space.langbot.app
+    depends_on:
+      postgres: {condition: service_healthy}
+    networks: [internal]
+
+  plugin-runtime:
+    image: rockchin/langbot:${LANGBOT_IMAGE_TAG}
+    container_name: langbot-cloud-plugin-runtime
+    restart: unless-stopped
+    command: [uv, run, python, -m, langbot_plugin.cli.__init__, rt]
+    environment:
+      LANGBOT_PLUGIN_RUNTIME_CONTROL_TOKEN: ${PLUGIN_RUNTIME_CONTROL_TOKEN}
+    volumes:
+      - plugin-data:/app/data
+      - /sys/fs/cgroup:/sys/fs/cgroup:rw
+    cgroup: host
+    privileged: true
+    expose: ["5400"]
+    networks: [internal]
+
+  box:
+    image: rockchin/langbot:${LANGBOT_IMAGE_TAG}
+    container_name: langbot-cloud-box
+    restart: unless-stopped
+    command: [uv, run, lbp, box, --host, 0.0.0.0, --ws-control-port, "5410"]
+    environment:
+      LANGBOT_BOX_CONTROL_TOKEN: ${BOX_CONTROL_TOKEN}
+      LANGBOT_BOX_ROOT: /app/data/box
+    volumes:
+      - box-data:/app/data/box
+      - /sys/fs/cgroup:/sys/fs/cgroup:rw
+    cgroup: host
+    privileged: true
+    expose: ["5410"]
+    networks: [internal]
+
+  core:
+    image: rockchin/langbot-cloud-core:${LANGBOT_IMAGE_TAG}
+    container_name: langbot-cloud-core
+    restart: unless-stopped
+    environment: *core-env
+    volumes:
+      - core-data:/app/data
+      - box-data:/app/data/box
+    depends_on:
+      postgres: {condition: service_healthy}
+      redis: {condition: service_healthy}
+      plugin-runtime: {condition: service_started}
+      box: {condition: service_started}
+    expose: ["5300"]
+    healthcheck:
+      test: [CMD-SHELL, "python -c 'import urllib.request; urllib.request.urlopen(\"http://127.0.0.1:5300/healthz\", timeout=3)'" ]
+      interval: 10s
+      timeout: 5s
+      retries: 30
+      start_period: 30s
+    networks: [internal, shared-network]
+
+networks:
+  internal:
+  shared-network:
+    external: true
+
+volumes:
+  postgres-data:
+  redis-data:
+  plugin-data:
+  box-data:
+  core-data:

docs/multi-tenant/implementation-decisions.md

@@ -81,10 +81,10 @@ This log records implementation choices made while delivering the Workspace arch
 - Decision: The MCP ASGI mount authenticates the API key once, binds an immutable per-request `RequestContext`, and every tool checks a fixed permission before calling tenant services with that same context.
 - Reason: Authenticating the transport without propagating Workspace identity into tool calls would leave the direct service path globally scoped.
 
-### Unreleased SDK protocol is pinned reproducibly without publishing
+### Released SDK protocol is pinned from PyPI
 
-- Decision: The SDK tenancy protocol is versioned as 0.4.18. This task does not create a GitHub release or publish PyPI because the user authorized pushing code, not a package release. After the SDK feature branch is final, LangBot's feature branch temporarily pins the exact pushed SDK Git commit. Before merging to master, the release gate is to publish `langbot-plugin==0.4.18` and replace the Git pin with the registry pin.
-- Reason: The current registry release does not contain the complete tenant action context and shared Runtime hardening. An exact Git commit is reproducible and keeps the feature branch testable without expanding release authority.
+- Decision: The SDK tenancy protocol is released as `langbot-plugin==0.5.0` and LangBot pins that exact registry version.
+- Reason: The final PyPI release contains the complete tenant action context and shared Runtime hardening, while the exact version pin keeps production installs reproducible.
 
 ### Cloud directory writes stay outside Core
 

pyproject.toml

@@ -71,7 +71,7 @@ dependencies = [
     "chromadb>=1.0.0,<2.0.0",
     "qdrant-client (>=1.15.1,<2.0.0)",
     "pyseekdb==1.1.0.post3",
-    "langbot-plugin @ git+https://github.com/langbot-app/langbot-plugin-sdk.git@1d65ed301a6afc52150a998043f73cd6032c8162",
+    "langbot-plugin==0.5.0",
     "asyncpg>=0.30.0",
     "line-bot-sdk>=3.19.0",
     "matrix-nio>=0.25.2",

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

@@ -14,6 +14,7 @@ from ....utils import bounded_executor
 from ....workspace.collaboration import MembershipPermissionError, WorkspaceCollaborationError
 from ....workspace.errors import WorkspaceNotFoundError
 from ....cloud.entitlements import EntitlementUnavailableError
+from ....cloud.quotas import WorkspaceQuotaExceededError
 from ....core.errors import TaskCapacityError
 from ..authz import AuthorizationError, Permission, permissions_for_role, require_permission
 from ..context import PrincipalContext, PrincipalType, RequestContext, WorkspaceContext
@@ -219,6 +220,8 @@ class RouterGroup(abc.ABC):
                         return self.http_status(403, e.code, str(e))
                     if isinstance(e, WorkspaceCollaborationError):
                         return self.http_status(400, e.code, str(e))
+                    if isinstance(e, WorkspaceQuotaExceededError):
+                        return self.http_status(409, e.error_code, str(e))
                     if isinstance(e, TaskCapacityError):
                         return self.http_status(429, 'task_capacity_exceeded', str(e))
                     if isinstance(

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

@@ -410,6 +410,7 @@ class UserRouterGroup(group.RouterGroup):
                     'token': token,
                     'user': account.user,
                     'workspace_uuid': access.workspace.uuid,
+                    'return_path': launch.get('return_path', '/home'),
                 }
             )
         except SpaceLaunchError:

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

@@ -4,6 +4,7 @@ import uuid
 import sqlalchemy
 
 from ....core import app
+from ....cloud.quotas import require_resource_capacity, resolve_workspace_quota
 from ....entity.persistence import bot as persistence_bot
 from ....entity.persistence import pipeline as persistence_pipeline
 from ....workspace.errors import WorkspaceNotFoundError
@@ -101,20 +102,21 @@ class BotService:
     async def create_bot(self, context: TenantContext, bot_data: dict) -> str:
         """Create bot"""
         workspace_uuid = require_workspace_uuid(context)
-        # Check limitation
         limitation = self.ap.instance_config.data.get('system', {}).get('limitation', {})
-        max_bots = limitation.get('max_bots', -1)
-        if max_bots >= 0:
-            existing_bots = await self.get_bots(context)
-            if len(existing_bots) >= max_bots:
-                raise ValueError(f'Maximum number of bots ({max_bots}) reached')
+        quota = await resolve_workspace_quota(
+            self.ap,
+            workspace_uuid,
+            'bots.max',
+            fallback=limitation.get('max_bots', -1),
+        )
 
         # TODO: 检查配置信息格式
         bot_data = bot_data.copy()
         bot_data['uuid'] = str(uuid.uuid4())
         bot_data['workspace_uuid'] = workspace_uuid
 
-        # bind the most recently updated pipeline if any exist
+        # Preserve the legacy flat-row result shape for this optional lookup;
+        # quota admission and insertion below still share one transaction.
         result = await self.ap.persistence_mgr.execute_async(
             scope_statement(
                 sqlalchemy.select(persistence_pipeline.LegacyPipeline),
@@ -129,7 +131,25 @@ class BotService:
             bot_data['use_pipeline_uuid'] = pipeline.uuid
             bot_data['use_pipeline_name'] = pipeline.name
 
-        await self.ap.persistence_mgr.execute_async(sqlalchemy.insert(persistence_bot.Bot).values(bot_data))
+        async def persist(execute) -> None:
+            await require_resource_capacity(
+                execute,
+                workspace_uuid=workspace_uuid,
+                model=persistence_bot.Bot,
+                quota=quota,
+                resource_name='bots',
+            )
+
+            await execute(sqlalchemy.insert(persistence_bot.Bot).values(bot_data))
+
+        tenant_uow = getattr(self.ap.persistence_mgr, 'tenant_uow', None)
+        if quota.requires_transaction_lock:
+            if not callable(tenant_uow):
+                raise RuntimeError('Cloud bot quota enforcement requires transactional persistence')
+            async with tenant_uow(workspace_uuid) as uow:
+                await persist(uow.execute)
+        else:
+            await persist(self.ap.persistence_mgr.execute_async)
 
         bot = await self.get_bot(context, bot_data['uuid'], include_secret=True)
 

src/langbot/pkg/cloud/bootstrap.py

@@ -138,8 +138,14 @@ class VerifiedCloudDeployment:
         if plugin_worker.get('require_hard_limits') is not True:
             raise CloudBootstrapError('Cloud Runtime requires plugin.worker.require_hard_limits=true')
         box_config = config.get('box', {})
-        if box_config.get('enabled') is not True:
-            raise CloudBootstrapError('Cloud runtime requires box.enabled=true')
+        box_enabled = box_config.get('enabled')
+        if box_enabled is False:
+            # Explicitly disabling Box removes the sandbox surface entirely and
+            # therefore does not weaken tenant isolation. Validate the strict
+            # runtime/admission contract only when the surface is enabled.
+            return
+        if box_enabled is not True:
+            raise CloudBootstrapError('Cloud runtime requires box.enabled to be an explicit boolean')
         if box_config.get('backend') != 'nsjail':
             raise CloudBootstrapError('Cloud runtime requires box.backend=nsjail')
         runtime_endpoint = str(box_config.get('runtime', {}).get('endpoint', '') or '').strip()

src/langbot/pkg/cloud/launch.py

@@ -3,9 +3,11 @@ from __future__ import annotations
 import asyncio
 import base64
 import binascii
+import datetime
 import hashlib
 import heapq
 import json
+import math
 import os
 import time
 import typing
@@ -14,6 +16,10 @@ from collections.abc import Callable, Iterable
 from cryptography.exceptions import InvalidSignature
 from cryptography.hazmat.primitives import serialization
 from cryptography.hazmat.primitives.asymmetric.ed25519 import Ed25519PublicKey
+import sqlalchemy
+from sqlalchemy.dialects.postgresql import insert as pg_insert
+
+from ..entity.persistence.cloud_directory import SpaceLaunchAssertionConsumption
 
 if typing.TYPE_CHECKING:
     from ..core.app import Application
@@ -119,21 +125,30 @@ class SpaceLaunchService:
         *,
         expected_workspace_uuid: str | None = None,
     ) -> dict[str, str]:
-        claims = self._verify_assertion(assertion)
+        claims, clock_skew_seconds = self._verify_assertion(assertion)
         payload = claims.get('payload')
         if not isinstance(payload, dict):
             raise SpaceLaunchError('Launch assertion payload must be a JSON object')
         account_uuid = _required_string(payload, 'account_uuid')
         workspace_uuid = _required_string(payload, 'workspace_uuid')
+        return_path = _required_string(payload, 'return_path')
+        if (
+            not return_path.startswith('/')
+            or return_path.startswith('//')
+            or any(character in return_path for character in ('\\', '\r', '\n', '\t'))
+        ):
+            raise SpaceLaunchError('Launch assertion return path is invalid')
         if expected_workspace_uuid is not None and workspace_uuid != expected_workspace_uuid:
             raise SpaceLaunchError('Launch assertion targets another Workspace')
-        await self._consume_jti(_required_string(claims, 'jti'), _required_int(claims, 'exp', minimum=1))
+        replay_retention_expires_at = _required_int(claims, 'exp', minimum=1) + math.ceil(clock_skew_seconds)
+        await self._consume_jti(_required_string(claims, 'jti'), replay_retention_expires_at)
         return {
             'account_uuid': account_uuid,
             'workspace_uuid': workspace_uuid,
+            'return_path': return_path,
         }
 
-    def _verify_assertion(self, token: str) -> dict[str, typing.Any]:
+    def _verify_assertion(self, token: str) -> tuple[dict[str, typing.Any], float]:
         if not getattr(getattr(self.ap, 'deployment', None), 'multi_workspace_enabled', False):
             raise SpaceLaunchError('Space direct launch requires verified Cloud mode')
         public_key, key_id, clock_skew_seconds = self._trust_config()
@@ -184,7 +199,7 @@ class SpaceLaunchService:
             raise SpaceLaunchError('Launch assertion is expired')
         if expires_at <= max(issued_at, not_before):
             raise SpaceLaunchError('Launch assertion expiry must follow issue time')
-        return claims
+        return claims, clock_skew_seconds
 
     def _trust_config(self) -> tuple[Ed25519PublicKey, str, float]:
         data = getattr(getattr(self.ap, 'instance_config', None), 'data', {}) or {}
@@ -214,19 +229,39 @@ class SpaceLaunchService:
     async def _consume_jti(self, jti: str, expires_at: int) -> None:
         digest = hashlib.sha256(jti.encode('utf-8')).hexdigest()
         now = int(self._wall_time())
+        persistence_mgr = getattr(self.ap, 'persistence_mgr', None)
+        instance_uuid = str(self.ap.workspace_service.instance_uuid)
+        if persistence_mgr is not None:
+            expires_at_datetime = datetime.datetime.fromtimestamp(expires_at, tz=datetime.timezone.utc)
+            now_datetime = datetime.datetime.fromtimestamp(now, tz=datetime.timezone.utc)
+            async with persistence_mgr.directory_projection_uow(instance_uuid) as uow:
+                await uow.session.execute(
+                    sqlalchemy.delete(SpaceLaunchAssertionConsumption).where(
+                        SpaceLaunchAssertionConsumption.instance_uuid == instance_uuid,
+                        SpaceLaunchAssertionConsumption.expires_at < now_datetime,
+                    )
+                )
+                statement = (
+                    pg_insert(SpaceLaunchAssertionConsumption)
+                    .values(instance_uuid=instance_uuid, jti=digest, expires_at=expires_at_datetime)
+                    .on_conflict_do_nothing(index_elements=['instance_uuid', 'jti'])
+                    .returning(SpaceLaunchAssertionConsumption.jti)
+                )
+                result = await uow.session.execute(statement)
+                if result.scalar_one_or_none() is None:
+                    raise SpaceLaunchError('Launch assertion has already been consumed')
+            return
+
+        # Lightweight unit-test and OSS compatibility fallback. Verified Cloud
+        # runtime always supplies the durable PostgreSQL persistence manager.
         async with self._replay_lock:
             self._prune_consumed_jtis(now)
             if digest in self._consumed_jtis:
                 raise SpaceLaunchError('Launch assertion has already been consumed')
             if len(self._consumed_jtis) >= _CONSUMED_JTI_MAX_ENTRIES:
-                # Evicting a still-valid digest would make a signed launch
-                # assertion replayable. Bound memory by failing closed instead.
                 raise SpaceLaunchError('Launch assertion replay cache capacity reached')
             self._consumed_jtis[digest] = expires_at
-            heapq.heappush(
-                self._consumed_jti_expiry_heap,
-                (expires_at, digest),
-            )
+            heapq.heappush(self._consumed_jti_expiry_heap, (expires_at, digest))
 
     def _prune_consumed_jtis(self, now: int) -> None:
         while self._consumed_jti_expiry_heap:

src/langbot/pkg/cloud/quotas.py

@@ -0,0 +1,82 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import Any, Awaitable, Callable
+
+import sqlalchemy
+
+from ..entity.persistence import workspace as persistence_workspace
+from .entitlements import EntitlementResolver
+
+
+Execute = Callable[[Any], Awaitable[Any]]
+
+
+class WorkspaceQuotaExceededError(ValueError):
+    """A stable business error raised when a workspace has no free slots."""
+
+    error_code = 'workspace_quota_exceeded'
+
+    def __init__(self, resource_name: str, limit: int) -> None:
+        self.resource_name = resource_name
+        self.limit = limit
+        super().__init__(f'Maximum number of {resource_name} ({limit}) reached')
+
+
+@dataclass(frozen=True, slots=True)
+class WorkspaceQuota:
+    limit: int
+    requires_transaction_lock: bool
+
+
+async def resolve_workspace_quota(
+    ap: Any,
+    workspace_uuid: str,
+    limit_name: str,
+    *,
+    fallback: int = -1,
+) -> WorkspaceQuota:
+    """Resolve a plan-agnostic Cloud limit while preserving OSS configuration."""
+
+    resolver = getattr(ap, 'entitlement_resolver', None)
+    if isinstance(resolver, EntitlementResolver):
+        snapshot = await resolver.resolve(workspace_uuid)
+        return WorkspaceQuota(
+            limit=snapshot.limit(limit_name),
+            requires_transaction_lock=True,
+        )
+    return WorkspaceQuota(limit=fallback, requires_transaction_lock=False)
+
+
+async def lock_workspace_for_quota(execute: Execute, workspace_uuid: str) -> None:
+    """Serialize quota checks on the durable Workspace row within one transaction."""
+
+    result = await execute(
+        sqlalchemy.select(persistence_workspace.Workspace.uuid)
+        .where(persistence_workspace.Workspace.uuid == workspace_uuid)
+        .with_for_update()
+    )
+    if result.first() is None:
+        raise ValueError('Workspace does not exist')
+
+
+async def require_resource_capacity(
+    execute: Execute,
+    *,
+    workspace_uuid: str,
+    model: type,
+    quota: WorkspaceQuota,
+    resource_name: str,
+    workspace_locked: bool = False,
+) -> None:
+    if quota.limit < 0:
+        return
+    if quota.requires_transaction_lock and not workspace_locked:
+        await lock_workspace_for_quota(execute, workspace_uuid)
+    result = await execute(
+        sqlalchemy.select(sqlalchemy.func.count())
+        .select_from(model)
+        .where(model.workspace_uuid == workspace_uuid)
+    )
+    if int(result.scalar_one()) >= quota.limit:
+        raise WorkspaceQuotaExceededError(resource_name, quota.limit)

src/langbot/pkg/entity/persistence/cloud_directory.py

@@ -67,3 +67,26 @@ class DirectoryProjectionInbox(Base):
             name='ck_directory_projection_inbox_fingerprint',
         ),
     )
+
+
+class SpaceLaunchAssertionConsumption(Base):
+    """Durable, instance-scoped replay ledger for signed Space launch assertions."""
+
+    __tablename__ = 'space_launch_assertion_consumptions'
+
+    instance_uuid = sqlalchemy.Column(sqlalchemy.String(255), primary_key=True)
+    jti = sqlalchemy.Column(sqlalchemy.String(255), primary_key=True)
+    expires_at = sqlalchemy.Column(sqlalchemy.DateTime(timezone=True), nullable=False)
+    consumed_at = sqlalchemy.Column(
+        sqlalchemy.DateTime(timezone=True),
+        nullable=False,
+        server_default=sqlalchemy.func.now(),
+    )
+
+    __table_args__ = (
+        sqlalchemy.Index(
+            'ix_space_launch_assertion_consumptions_expiry',
+            'instance_uuid',
+            'expires_at',
+        ),
+    )

src/langbot/pkg/persistence/alembic/versions/0016_space_launch_replay.py

@@ -0,0 +1,57 @@
+"""add durable replay protection for signed Space launch assertions
+
+Revision ID: 0016_space_launch_replay
+Revises: 0015_cloud_core_collab
+Create Date: 2026-07-31
+"""
+
+from __future__ import annotations
+
+import sqlalchemy as sa
+from alembic import op
+
+revision = '0016_space_launch_replay'
+down_revision = '0015_cloud_core_collab'
+branch_labels = None
+depends_on = None
+
+_TABLE = 'space_launch_assertion_consumptions'
+_POLICY = 'langbot_directory_projection'
+_SETTING = "NULLIF(current_setting('langbot.directory_instance_uuid', true), '')"
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    if _TABLE not in set(sa.inspect(conn).get_table_names()):
+        op.create_table(
+            _TABLE,
+            sa.Column('instance_uuid', sa.String(255), nullable=False),
+            sa.Column('jti', sa.String(255), nullable=False),
+            sa.Column('expires_at', sa.DateTime(timezone=True), nullable=False),
+            sa.Column('consumed_at', sa.DateTime(timezone=True), server_default=sa.func.now(), nullable=False),
+            sa.PrimaryKeyConstraint('instance_uuid', 'jti'),
+        )
+        op.create_index(
+            'ix_space_launch_assertion_consumptions_expiry',
+            _TABLE,
+            ['instance_uuid', 'expires_at'],
+            unique=False,
+        )
+    if conn.dialect.name == 'postgresql':
+        table = conn.dialect.identifier_preparer.quote(_TABLE)
+        policy = conn.dialect.identifier_preparer.quote(_POLICY)
+        expression = f'instance_uuid::text = {_SETTING}'
+        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} ON {table}'))
+        op.execute(
+            sa.text(
+                f'CREATE POLICY {policy} ON {table} AS PERMISSIVE FOR ALL TO PUBLIC '
+                f'USING ({expression}) WITH CHECK ({expression})'
+            )
+        )
+
+
+def downgrade() -> None:
+    if _TABLE in set(sa.inspect(op.get_bind()).get_table_names()):
+        op.drop_table(_TABLE)

src/langbot/pkg/persistence/tenant_uow.py

@@ -75,6 +75,7 @@ TENANT_TABLE_COLUMNS: dict[str, str] = {
 DIRECTORY_PROJECTION_TABLE_COLUMNS: dict[str, str] = {
     'directory_projection_states': 'instance_uuid',
     'directory_projection_inbox': 'instance_uuid',
+    'space_launch_assertion_consumptions': 'instance_uuid',
 }
 
 DIRECTORY_PROJECTED_TENANT_TABLES = frozenset(

src/langbot/pkg/plugin/connector.py

@@ -19,6 +19,11 @@ from urllib.parse import urljoin, urlparse
 from langbot_plugin.api.entities.builtin.pipeline.query import provider_session
 
 from ..core import app
+from ..cloud.quotas import (
+    lock_workspace_for_quota,
+    require_resource_capacity,
+    resolve_workspace_quota,
+)
 from . import handler
 from .archive import inspect_plugin_archive_metadata
 from .github import (
@@ -1295,6 +1300,11 @@ class PluginRuntimeConnector(ManagedRuntimeConnector):
         install_info: dict[str, Any],
         artifact_digest: str,
     ) -> tuple[InstallationBinding, str | None, bool]:
+        quota = await resolve_workspace_quota(
+            self.ap,
+            execution_context.workspace_uuid,
+            'plugins.max',
+        )
         safe_install_info = {
             key: value
             for key, value in install_info.items()
@@ -1316,9 +1326,19 @@ class PluginRuntimeConnector(ManagedRuntimeConnector):
         )
 
         async def persist(execute):
+            if quota.requires_transaction_lock:
+                await lock_workspace_for_quota(execute, execution_context.workspace_uuid)
             result = await execute(statement)
             setting = result.first()
             if setting is None:
+                await require_resource_capacity(
+                    execute,
+                    workspace_uuid=execution_context.workspace_uuid,
+                    model=persistence_plugin.PluginSetting,
+                    quota=quota,
+                    resource_name='plugins',
+                    workspace_locked=quota.requires_transaction_lock,
+                )
                 installation_uuid = str(uuid.uuid4())
                 runtime_revision = 1
                 previous_digest = None
@@ -1373,6 +1393,8 @@ class PluginRuntimeConnector(ManagedRuntimeConnector):
             )
 
         tenant_uow = getattr(self.ap.persistence_mgr, 'tenant_uow', None)
+        if quota.requires_transaction_lock and not callable(tenant_uow):
+            raise RuntimeError('Cloud plugin quota enforcement requires transactional persistence')
         if callable(tenant_uow):
             async with tenant_uow(execution_context.workspace_uuid) as uow:
                 return await persist(uow.execute)

tests/integration/persistence/test_workspace_quota_postgres.py

@@ -0,0 +1,137 @@
+"""PostgreSQL integration coverage for durable workspace quota locking.
+
+Run with TEST_POSTGRES_URL=postgresql+asyncpg://... pytest ...
+"""
+
+from __future__ import annotations
+
+import asyncio
+import os
+import uuid
+
+import pytest
+import sqlalchemy as sa
+from sqlalchemy.ext.asyncio import async_sessionmaker, create_async_engine
+from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column
+
+from langbot.pkg.cloud import quotas as quota_module
+from langbot.pkg.cloud.quotas import WorkspaceQuota, WorkspaceQuotaExceededError, require_resource_capacity
+
+
+pytestmark = [pytest.mark.integration, pytest.mark.slow, pytest.mark.asyncio]
+
+
+class _Base(DeclarativeBase):
+    pass
+
+
+class _Workspace(_Base):
+    __tablename__ = 'quota_integration_workspaces'
+
+    uuid: Mapped[str] = mapped_column(sa.String(36), primary_key=True)
+
+
+class _Resource(_Base):
+    __tablename__ = 'quota_integration_resources'
+
+    uuid: Mapped[str] = mapped_column(sa.String(36), primary_key=True)
+    workspace_uuid: Mapped[str] = mapped_column(
+        sa.String(36),
+        sa.ForeignKey('quota_integration_workspaces.uuid', ondelete='CASCADE'),
+        nullable=False,
+        index=True,
+    )
+
+
+@pytest.fixture
+async def quota_postgres(monkeypatch):
+    url = os.environ.get('TEST_POSTGRES_URL')
+    if not url:
+        pytest.skip('TEST_POSTGRES_URL not set')
+    if url.startswith('postgresql://'):
+        url = url.replace('postgresql://', 'postgresql+asyncpg://', 1)
+
+    engine = create_async_engine(url, pool_size=5, max_overflow=0)
+    monkeypatch.setattr(quota_module.persistence_workspace, 'Workspace', _Workspace)
+    async with engine.begin() as connection:
+        await connection.run_sync(_Base.metadata.drop_all)
+        await connection.run_sync(_Base.metadata.create_all)
+    try:
+        yield url, engine
+    finally:
+        async with engine.begin() as connection:
+            await connection.run_sync(_Base.metadata.drop_all)
+        await engine.dispose()
+
+
+async def test_workspace_row_lock_is_atomic_isolated_and_survives_pool_restart(quota_postgres) -> None:
+    url, engine = quota_postgres
+    workspace_a = str(uuid.uuid4())
+    workspace_b = str(uuid.uuid4())
+    quota = WorkspaceQuota(limit=1, requires_transaction_lock=True)
+    sessions = async_sessionmaker(engine, expire_on_commit=False)
+
+    async with engine.begin() as connection:
+        await connection.execute(sa.insert(_Workspace), [{'uuid': workspace_a}, {'uuid': workspace_b}])
+
+    lock_acquired = asyncio.Event()
+    release_first = asyncio.Event()
+
+    async def admit(workspace_uuid: str, *, hold: bool = False) -> None:
+        async with sessions() as session:
+            async with session.begin():
+                await require_resource_capacity(
+                    session.execute,
+                    workspace_uuid=workspace_uuid,
+                    model=_Resource,
+                    quota=quota,
+                    resource_name='resources',
+                )
+                if hold:
+                    lock_acquired.set()
+                    await release_first.wait()
+                await session.execute(
+                    sa.insert(_Resource).values(uuid=str(uuid.uuid4()), workspace_uuid=workspace_uuid)
+                )
+
+    first = asyncio.create_task(admit(workspace_a, hold=True))
+    await asyncio.wait_for(lock_acquired.wait(), timeout=2)
+    same_workspace = asyncio.create_task(admit(workspace_a))
+    other_workspace = asyncio.create_task(admit(workspace_b))
+
+    await asyncio.wait_for(other_workspace, timeout=2)
+    assert not same_workspace.done(), 'same-workspace transaction bypassed SELECT FOR UPDATE'
+
+    release_first.set()
+    await first
+    with pytest.raises(WorkspaceQuotaExceededError, match=r'Maximum number of resources \(1\) reached'):
+        await same_workspace
+
+    async with sessions() as session:
+        counts = dict(
+            (
+                await session.execute(
+                    sa.select(_Resource.workspace_uuid, sa.func.count())
+                    .group_by(_Resource.workspace_uuid)
+                    .order_by(_Resource.workspace_uuid)
+                )
+            ).all()
+        )
+    assert counts == {workspace_a: 1, workspace_b: 1}
+
+    await engine.dispose()
+    restarted_engine = create_async_engine(url, pool_size=2, max_overflow=0)
+    restarted_sessions = async_sessionmaker(restarted_engine, expire_on_commit=False)
+    try:
+        async with restarted_sessions() as session:
+            async with session.begin():
+                with pytest.raises(WorkspaceQuotaExceededError):
+                    await require_resource_capacity(
+                        session.execute,
+                        workspace_uuid=workspace_a,
+                        model=_Resource,
+                        quota=quota,
+                        resource_name='resources',
+                    )
+    finally:
+        await restarted_engine.dispose()

tests/unit_tests/api/http/test_internal_error_responses.py

@@ -9,6 +9,7 @@ import quart
 
 from langbot.pkg.api.http.controller import group
 from langbot.pkg.api.http.controller.groups.webhooks import WebhookRouterGroup
+from langbot.pkg.cloud.quotas import WorkspaceQuotaExceededError
 from langbot.pkg.utils.bounded_executor import (
     BlockingWorkCapacityError,
     current_blocking_work_scope,
@@ -48,6 +49,16 @@ class _BlockingCapacityRouterGroup(group.RouterGroup):
             raise BlockingWorkCapacityError('Workspace blocking executor capacity reached')
 
 
+class _QuotaRouterGroup(group.RouterGroup):
+    name = 'quota-test'
+    path = '/quota-test'
+
+    async def initialize(self) -> None:
+        @self.route('', methods=['POST'], auth_type=group.AuthType.NONE)
+        async def _():
+            raise WorkspaceQuotaExceededError('bots', 2)
+
+
 class _InvalidAccountRouterGroup(group.RouterGroup):
     name = 'invalid-account-test'
     path = '/invalid-account-test'
@@ -130,6 +141,20 @@ async def test_blocking_work_capacity_maps_to_retryable_http_response():
     }
 
 
+async def test_workspace_quota_maps_to_stable_conflict_response():
+    application = SimpleNamespace(logger=Mock())
+    quart_app = quart.Quart(__name__)
+    await _QuotaRouterGroup(application, quart_app).initialize()
+
+    response = await quart_app.test_client().post('/quota-test')
+
+    assert response.status_code == 409
+    assert await response.get_json() == {
+        'code': 'workspace_quota_exceeded',
+        'msg': 'Maximum number of bots (2) reached',
+    }
+
+
 async def test_public_webhook_carries_scope_without_holding_database_session():
     class ScopeOnlyPersistenceManager:
         mode = SimpleNamespace(value='cloud_runtime')

tests/unit_tests/api/service/test_bot_service.py

@@ -311,10 +311,9 @@ class TestBotServiceCreateBot:
         ap.platform_mgr = SimpleNamespace()
         ap.platform_mgr.load_bot = AsyncMock()
 
-        # Mock get_bots to return 2 bots already
-        bot1 = _create_mock_bot(bot_uuid='uuid-1')
-        bot2 = _create_mock_bot(bot_uuid='uuid-2')
-        mock_result = _create_mock_result([bot1, bot2])
+        # Mock the atomic count query to report 2 existing bots.
+        mock_result = _create_mock_result()
+        mock_result.scalar_one = Mock(return_value=2)
         ap.persistence_mgr.execute_async = AsyncMock(return_value=mock_result)
         ap.persistence_mgr.serialize_model = Mock(return_value={'uuid': 'uuid-1', 'name': 'Bot 1'})
 

tests/unit_tests/api/service/test_cloud_bot_quota_concurrency.py

@@ -0,0 +1,129 @@
+from __future__ import annotations
+
+import asyncio
+from collections import defaultdict
+from types import SimpleNamespace
+from unittest.mock import AsyncMock
+
+import pytest
+import sqlalchemy
+
+from langbot.pkg.api.http.service.bot import BotService
+from langbot.pkg.cloud.entitlements import EntitlementResolver, EntitlementSnapshot
+
+
+INSTANCE_UUID = 'cloud-instance'
+WORKSPACE_A = '11111111-1111-1111-1111-111111111111'
+WORKSPACE_B = '22222222-2222-2222-2222-222222222222'
+
+
+class _Provider:
+    async def get_workspace_entitlement(self, workspace_uuid: str) -> EntitlementSnapshot:
+        return EntitlementSnapshot(
+            instance_uuid=INSTANCE_UUID,
+            workspace_uuid=workspace_uuid,
+            entitlement_revision=1,
+            status='active',
+            not_before=0,
+            expires_at=4_102_444_800,
+            features={},
+            limits={'bots.max': 2},
+        )
+
+
+class _Result:
+    def __init__(self, *, first=None, scalar=None) -> None:
+        self._first = first
+        self._scalar = scalar
+
+    def first(self):
+        return self._first
+
+    def scalar_one(self):
+        return self._scalar
+
+
+class _TenantUow:
+    def __init__(self, manager: '_Persistence', workspace_uuid: str) -> None:
+        self.manager = manager
+        self.workspace_uuid = workspace_uuid
+        self.lock = manager.locks[workspace_uuid]
+
+    async def __aenter__(self):
+        await self.lock.acquire()
+        return self
+
+    async def __aexit__(self, exc_type, exc, tb):
+        self.lock.release()
+
+    async def execute(self, statement):
+        sql = str(statement)
+        if isinstance(statement, sqlalchemy.sql.dml.Insert):
+            assert statement.table.name == 'bots'
+            self.manager.bots[self.workspace_uuid].append(statement.compile().params)
+            return _Result()
+        if 'FROM workspaces' in sql:
+            assert statement._for_update_arg is not None
+            self.manager.workspace_locks_seen += 1
+            return _Result(first=(self.workspace_uuid,))
+        if 'count(' in sql.lower() and 'FROM bots' in sql:
+            return _Result(scalar=len(self.manager.bots[self.workspace_uuid]))
+        if 'FROM legacy_pipelines' in sql:
+            return _Result(first=None)
+        raise AssertionError(f'unexpected statement: {sql}')
+
+
+class _Persistence:
+    def __init__(self) -> None:
+        self.locks = defaultdict(asyncio.Lock)
+        self.bots = defaultdict(list)
+        self.workspace_locks_seen = 0
+
+    def tenant_uow(self, workspace_uuid: str) -> _TenantUow:
+        return _TenantUow(self, workspace_uuid)
+
+    async def execute_async(self, statement):
+        assert 'FROM legacy_pipelines' in str(statement)
+        return _Result(first=None)
+
+
+async def _service(manager: _Persistence) -> BotService:
+    resolver = EntitlementResolver(INSTANCE_UUID, _Provider())
+    await resolver.reconcile_active_workspaces({WORKSPACE_A, WORKSPACE_B})
+    ap = SimpleNamespace(
+        entitlement_resolver=resolver,
+        persistence_mgr=manager,
+        instance_config=SimpleNamespace(data={'system': {'limitation': {'max_bots': 99}}}),
+        platform_mgr=SimpleNamespace(load_bot=AsyncMock()),
+    )
+    service = BotService(ap)
+    service.get_bot = AsyncMock(return_value={'uuid': 'created'})
+    return service
+
+
+@pytest.mark.asyncio
+async def test_cloud_bot_quota_is_atomic_isolated_and_persists_across_service_restart() -> None:
+    manager = _Persistence()
+    service = await _service(manager)
+
+    async def create(workspace_uuid: str, index: int):
+        return await service.create_bot(workspace_uuid, {'name': f'bot-{index}'})
+
+    results = await asyncio.gather(
+        *(create(WORKSPACE_A, index) for index in range(8)),
+        *(create(WORKSPACE_B, index) for index in range(8)),
+        return_exceptions=True,
+    )
+
+    successes = [result for result in results if isinstance(result, str)]
+    failures = [result for result in results if isinstance(result, ValueError)]
+    assert len(successes) == 4
+    assert len(failures) == 12
+    assert len(manager.bots[WORKSPACE_A]) == 2
+    assert len(manager.bots[WORKSPACE_B]) == 2
+    assert manager.workspace_locks_seen == 16
+
+    restarted_service = await _service(manager)
+    with pytest.raises(ValueError, match=r'Maximum number of bots \(2\) reached'):
+        await restarted_service.create_bot(WORKSPACE_A, {'name': 'after-restart'})
+    assert len(manager.bots[WORKSPACE_A]) == 2

tests/unit_tests/cloud/test_bootstrap.py

@@ -228,10 +228,23 @@ async def test_cloud_pgvector_contract_is_fail_closed(pgvector_config, message):
         )
 
 
+async def test_cloud_runtime_allows_explicitly_disabled_box():
+    config = _cloud_config()
+    config['box']['enabled'] = False
+
+    deployment = await resolve_deployment(
+        instance_uuid='instance-a',
+        instance_config=config,
+        entry_points=lambda: _EntryPoints([_EntryPoint(_Provider())]),
+        now=1_000,
+    )
+
+    assert isinstance(deployment, VerifiedCloudDeployment)
+
+
 @pytest.mark.parametrize(
     ('mutate', 'message'),
     [
-        (lambda config: config['box'].update(enabled=False), 'box.enabled=true'),
         (lambda config: config['box'].update(backend='docker'), 'box.backend=nsjail'),
         (lambda config: config['box']['runtime'].update(endpoint=''), 'box.runtime.endpoint'),
         (

tests/unit_tests/cloud/test_space_launch.py

@@ -48,6 +48,7 @@ def _claims(*, now: int, jti: str | None = None, workspace_uuid: str = WORKSPACE
         'payload': {
             'account_uuid': ACCOUNT_UUID,
             'workspace_uuid': workspace_uuid,
+            'return_path': '/',
         },
     }
 
@@ -81,7 +82,27 @@ async def test_consumes_valid_workspace_launch_assertion_once():
 
     launch = await service.consume_assertion(token, expected_workspace_uuid=WORKSPACE_UUID)
 
-    assert launch == {'account_uuid': ACCOUNT_UUID, 'workspace_uuid': WORKSPACE_UUID}
+    assert launch == {
+        'account_uuid': ACCOUNT_UUID,
+        'workspace_uuid': WORKSPACE_UUID,
+        'return_path': '/',
+    }
+    with pytest.raises(SpaceLaunchError, match='already been consumed'):
+        await service.consume_assertion(token, expected_workspace_uuid=WORKSPACE_UUID)
+
+
+async def test_consumed_assertion_remains_blocked_through_clock_skew_window():
+    private_key = Ed25519PrivateKey.generate()
+    now = int(time.time())
+    service = _service(private_key, now=now)
+    claims = _claims(now=now)
+    claims['iat'] = now - 10
+    claims['nbf'] = now - 10
+    claims['exp'] = now - 1
+    token = _sign(private_key, claims)
+
+    await service.consume_assertion(token, expected_workspace_uuid=WORKSPACE_UUID)
+
     with pytest.raises(SpaceLaunchError, match='already been consumed'):
         await service.consume_assertion(token, expected_workspace_uuid=WORKSPACE_UUID)
 
@@ -162,3 +183,15 @@ async def test_rejects_invalid_signature_and_non_cloud_mode():
     oss_service.ap.deployment.multi_workspace_enabled = False
     with pytest.raises(SpaceLaunchError, match='verified Cloud mode'):
         await oss_service.consume_assertion(token, expected_workspace_uuid=WORKSPACE_UUID)
+
+
+@pytest.mark.asyncio
+async def test_rejects_unsafe_signed_return_path() -> None:
+    private_key = Ed25519PrivateKey.generate()
+    now = int(time.time())
+    service = _service(private_key, now=now)
+    claims = _claims(now=now)
+    claims['payload']['return_path'] = '//evil.example'
+
+    with pytest.raises(SpaceLaunchError, match='return path'):
+        await service.consume_assertion(_sign(private_key, claims))

tests/unit_tests/cloud/test_workspace_quotas.py

@@ -0,0 +1,102 @@
+from __future__ import annotations
+
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, Mock
+
+import pytest
+import sqlalchemy
+
+from langbot.pkg.cloud.entitlements import EntitlementResolver, EntitlementSnapshot
+from langbot.pkg.cloud.quotas import (
+    WorkspaceQuota,
+    require_resource_capacity,
+    resolve_workspace_quota,
+)
+from langbot.pkg.entity.persistence.bot import Bot
+
+
+WORKSPACE_UUID = '11111111-1111-1111-1111-111111111111'
+INSTANCE_UUID = 'cloud-instance'
+
+
+class _Provider:
+    def __init__(self, limits: dict[str, int]) -> None:
+        self.limits = limits
+
+    async def get_workspace_entitlement(self, workspace_uuid: str) -> EntitlementSnapshot:
+        return EntitlementSnapshot(
+            instance_uuid=INSTANCE_UUID,
+            workspace_uuid=workspace_uuid,
+            entitlement_revision=1,
+            status='active',
+            not_before=0,
+            expires_at=4_102_444_800,
+            features={},
+            limits=self.limits,
+            plan_name='test',
+        )
+
+
+async def _resolver(limits: dict[str, int]) -> EntitlementResolver:
+    resolver = EntitlementResolver(INSTANCE_UUID, _Provider(limits))
+    await resolver.reconcile_active_workspaces({WORKSPACE_UUID})
+    return resolver
+
+
+@pytest.mark.asyncio
+async def test_resolve_workspace_quota_uses_signed_cloud_limit() -> None:
+    ap = SimpleNamespace(entitlement_resolver=await _resolver({'bots.max': 2}))
+
+    quota = await resolve_workspace_quota(ap, WORKSPACE_UUID, 'bots.max', fallback=99)
+
+    assert quota == WorkspaceQuota(limit=2, requires_transaction_lock=True)
+
+
+@pytest.mark.asyncio
+async def test_resolve_workspace_quota_preserves_oss_fallback() -> None:
+    quota = await resolve_workspace_quota(SimpleNamespace(), WORKSPACE_UUID, 'bots.max', fallback=7)
+
+    assert quota == WorkspaceQuota(limit=7, requires_transaction_lock=False)
+
+
+@pytest.mark.asyncio
+async def test_require_resource_capacity_locks_workspace_before_counting() -> None:
+    statements: list[object] = []
+    lock_result = Mock()
+    lock_result.first.return_value = (WORKSPACE_UUID,)
+    count_result = Mock()
+    count_result.scalar_one.return_value = 1
+    execute = AsyncMock(side_effect=[lock_result, count_result])
+
+    await require_resource_capacity(
+        execute,
+        workspace_uuid=WORKSPACE_UUID,
+        model=Bot,
+        quota=WorkspaceQuota(limit=2, requires_transaction_lock=True),
+        resource_name='bots',
+    )
+
+    statements.extend(call.args[0] for call in execute.await_args_list)
+    assert len(statements) == 2
+    assert isinstance(statements[0], sqlalchemy.sql.Select)
+    assert statements[0]._for_update_arg is not None
+    assert 'workspaces' in str(statements[0])
+    assert 'count' in str(statements[1]).lower()
+
+
+@pytest.mark.asyncio
+async def test_require_resource_capacity_rejects_at_boundary() -> None:
+    lock_result = Mock()
+    lock_result.first.return_value = (WORKSPACE_UUID,)
+    count_result = Mock()
+    count_result.scalar_one.return_value = 2
+    execute = AsyncMock(side_effect=[lock_result, count_result])
+
+    with pytest.raises(ValueError, match=r'Maximum number of bots \(2\) reached'):
+        await require_resource_capacity(
+            execute,
+            workspace_uuid=WORKSPACE_UUID,
+            model=Bot,
+            quota=WorkspaceQuota(limit=2, requires_transaction_lock=True),
+            resource_name='bots',
+        )

tests/unit_tests/plugin/test_cloud_plugin_quota_concurrency.py

@@ -0,0 +1,191 @@
+from __future__ import annotations
+
+import asyncio
+from collections import defaultdict
+from types import SimpleNamespace
+
+import pytest
+import sqlalchemy
+
+from langbot.pkg.api.http.context import ExecutionContext
+from langbot.pkg.cloud.entitlements import EntitlementResolver, EntitlementSnapshot
+from langbot.pkg.cloud.quotas import WorkspaceQuotaExceededError
+from langbot.pkg.plugin.connector import PluginRuntimeConnector
+from langbot_plugin.runtime.plugin.mgr import PluginInstallSource
+
+
+INSTANCE_UUID = 'cloud-instance'
+WORKSPACE_A = '11111111-1111-1111-1111-111111111111'
+WORKSPACE_B = '22222222-2222-2222-2222-222222222222'
+
+
+class _Provider:
+    async def get_workspace_entitlement(self, workspace_uuid: str) -> EntitlementSnapshot:
+        return EntitlementSnapshot(
+            instance_uuid=INSTANCE_UUID,
+            workspace_uuid=workspace_uuid,
+            entitlement_revision=1,
+            status='active',
+            not_before=0,
+            expires_at=4_102_444_800,
+            features={},
+            limits={'plugins.max': 3},
+        )
+
+
+class _Result:
+    def __init__(self, *, first=None, scalar=None) -> None:
+        self._first = first
+        self._scalar = scalar
+
+    def first(self):
+        return self._first
+
+    def scalar_one(self):
+        return self._scalar
+
+
+class _TenantUow:
+    def __init__(self, manager: '_Persistence', workspace_uuid: str) -> None:
+        self.manager = manager
+        self.workspace_uuid = workspace_uuid
+        self.lock = manager.locks[workspace_uuid]
+
+    async def __aenter__(self):
+        await self.lock.acquire()
+        return self
+
+    async def __aexit__(self, exc_type, exc, tb):
+        self.lock.release()
+
+    async def execute(self, statement):
+        sql = str(statement)
+        params = statement.compile().params
+        if isinstance(statement, sqlalchemy.sql.dml.Insert):
+            assert statement.table.name == 'plugin_settings'
+            key = (params['plugin_author'], params['plugin_name'])
+            self.manager.plugins[self.workspace_uuid][key] = dict(params)
+            return _Result()
+        if isinstance(statement, sqlalchemy.sql.dml.Update):
+            return _Result()
+        if 'FROM workspaces' in sql:
+            assert statement._for_update_arg is not None
+            self.manager.workspace_locks_seen += 1
+            return _Result(first=(self.workspace_uuid,))
+        if 'count(' in sql.lower() and 'FROM plugin_settings' in sql:
+            return _Result(scalar=len(self.manager.plugins[self.workspace_uuid]))
+        if 'FROM plugin_settings' in sql:
+            author = next(value for name, value in params.items() if 'plugin_author' in name)
+            name = next(value for param, value in params.items() if 'plugin_name' in param)
+            row = self.manager.plugins[self.workspace_uuid].get((author, name))
+            if row is None:
+                return _Result(first=None)
+            return _Result(
+                first=SimpleNamespace(
+                    installation_uuid=row['installation_uuid'],
+                    runtime_revision=row['runtime_revision'],
+                    artifact_digest=row['artifact_digest'],
+                    install_info=row['install_info'],
+                )
+            )
+        raise AssertionError(f'unexpected statement: {sql}')
+
+
+class _Persistence:
+    def __init__(self) -> None:
+        self.locks = defaultdict(asyncio.Lock)
+        self.plugins = defaultdict(dict)
+        self.workspace_locks_seen = 0
+
+    def tenant_uow(self, workspace_uuid: str) -> _TenantUow:
+        return _TenantUow(self, workspace_uuid)
+
+
+async def _connector(manager: _Persistence) -> PluginRuntimeConnector:
+    resolver = EntitlementResolver(INSTANCE_UUID, _Provider())
+    await resolver.reconcile_active_workspaces({WORKSPACE_A, WORKSPACE_B})
+    connector = object.__new__(PluginRuntimeConnector)
+    connector.ap = SimpleNamespace(entitlement_resolver=resolver, persistence_mgr=manager)
+    return connector
+
+
+def _context(workspace_uuid: str) -> ExecutionContext:
+    return ExecutionContext(
+        instance_uuid=INSTANCE_UUID,
+        workspace_uuid=workspace_uuid,
+        placement_generation=1,
+        entitlement_revision=1,
+    )
+
+
+@pytest.mark.asyncio
+async def test_cloud_plugin_quota_is_atomic_isolated_and_persists_across_connector_restart() -> None:
+    manager = _Persistence()
+    connector = await _connector(manager)
+
+    async def install(workspace_uuid: str, index: int):
+        return await connector._persist_installation_package(
+            _context(workspace_uuid),
+            plugin_author='test-author',
+            plugin_name=f'plugin-{index}',
+            install_source=PluginInstallSource.MARKETPLACE,
+            install_info={'author': 'test-author', 'name': f'plugin-{index}'},
+            artifact_digest=f'{index:064x}',
+        )
+
+    results = await asyncio.gather(
+        *(install(WORKSPACE_A, index) for index in range(10)),
+        *(install(WORKSPACE_B, index) for index in range(10)),
+        return_exceptions=True,
+    )
+
+    successes = [result for result in results if isinstance(result, tuple)]
+    failures = [result for result in results if isinstance(result, WorkspaceQuotaExceededError)]
+    assert len(successes) == 6
+    assert len(failures) == 14
+    assert len(manager.plugins[WORKSPACE_A]) == 3
+    assert len(manager.plugins[WORKSPACE_B]) == 3
+    assert manager.workspace_locks_seen == 20
+
+    restarted_connector = await _connector(manager)
+    with pytest.raises(WorkspaceQuotaExceededError, match=r'Maximum number of plugins \(3\) reached'):
+        await restarted_connector._persist_installation_package(
+            _context(WORKSPACE_A),
+            plugin_author='test-author',
+            plugin_name='after-restart',
+            install_source=PluginInstallSource.MARKETPLACE,
+            install_info={},
+            artifact_digest='f' * 64,
+        )
+    assert len(manager.plugins[WORKSPACE_A]) == 3
+
+    installed_name = next(iter(manager.plugins[WORKSPACE_A]))[1]
+
+    async def reinstall():
+        return await restarted_connector._persist_installation_package(
+            _context(WORKSPACE_A),
+            plugin_author='test-author',
+            plugin_name=installed_name,
+            install_source=PluginInstallSource.MARKETPLACE,
+            install_info={'author': 'test-author', 'name': installed_name, 'revision': 2},
+            artifact_digest='e' * 64,
+        )
+
+    reinstall_results = await asyncio.gather(reinstall(), reinstall())
+    assert all(result[2] is True for result in reinstall_results)
+
+    mixed_results = await asyncio.gather(
+        reinstall(),
+        restarted_connector._persist_installation_package(
+            _context(WORKSPACE_A),
+            plugin_author='test-author',
+            plugin_name='new-at-capacity',
+            install_source=PluginInstallSource.MARKETPLACE,
+            install_info={},
+            artifact_digest='d' * 64,
+        ),
+        return_exceptions=True,
+    )
+    assert isinstance(mixed_results[0], tuple)
+    assert isinstance(mixed_results[1], WorkspaceQuotaExceededError)
+    assert len(manager.plugins[WORKSPACE_A]) == 3

uv.lock

@@ -2116,7 +2116,7 @@ requires-dist = [
     { name = "ebooklib", specifier = ">=0.18" },
     { name = "gewechat-client", specifier = ">=0.1.5" },
     { name = "html2text", specifier = ">=2024.2.26" },
-    { name = "langbot-plugin", git = "https://github.com/langbot-app/langbot-plugin-sdk.git?rev=1d65ed301a6afc52150a998043f73cd6032c8162" },
+    { name = "langbot-plugin", specifier = "==0.5.0" },
     { name = "langchain", specifier = ">=1.3.9" },
     { name = "langchain-core", specifier = ">=1.3.3" },
     { name = "langchain-text-splitters", specifier = ">=1.1.2" },
@@ -2182,8 +2182,8 @@ dev = [
 
 [[package]]
 name = "langbot-plugin"
-version = "0.4.18"
-source = { git = "https://github.com/langbot-app/langbot-plugin-sdk.git?rev=1d65ed301a6afc52150a998043f73cd6032c8162#1d65ed301a6afc52150a998043f73cd6032c8162" }
+version = "0.5.0"
+source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "aiofiles" },
     { name = "aiohttp" },
@@ -2203,6 +2203,10 @@ dependencies = [
     { name = "watchdog" },
     { name = "websockets" },
 ]
+sdist = { url = "https://files.pythonhosted.org/packages/5c/09/697037dea617a235c9b3df85174badfb44886e3c67149a928049839a959a/langbot_plugin-0.5.0.tar.gz", hash = "sha256:9b81fa0f73cde1fe199a746e03ad891f8ced8f4fa0d05aeb6d78bfe7d755a976", size = 464033, upload-time = "2026-07-30T19:22:57.503Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/d2/70/93e544c3a120953f4871266db9ef84ea9a58daf01d493fafa7c45674ad36/langbot_plugin-0.5.0-py3-none-any.whl", hash = "sha256:2b078db96d869de55d08304465974f51765e3cfe582ff79b32f09161292fb877", size = 300758, upload-time = "2026-07-30T19:22:56.248Z" },
+]
 
 [[package]]
 name = "langchain"

web/src/app/auth/space/callback/page.tsx

@@ -29,6 +29,7 @@ type SpaceOAuthLoginResult = {
   token: string;
   user: string;
   workspace_uuid?: string;
+  return_path?: string;
 };
 
 const pendingSpaceOAuthLogins = new Map<
@@ -63,6 +64,10 @@ function SpaceOAuthCallbackContent() {
   const [searchParams] = useSearchParams();
   const { t } = useTranslation();
   const isMountedRef = useRef(true);
+  const directLaunchFragmentRef = useRef<{
+    workspaceUuid: string | null;
+    launchAssertion: string | null;
+  } | null>(null);
 
   const [status, setStatus] = useState<
     'loading' | 'confirm' | 'success' | 'error'
@@ -106,7 +111,13 @@ function SpaceOAuthCallbackContent() {
           throw new Error('No Workspace is available for this Account');
         }
         if (response.workspace_uuid) {
-          navigate('/home', { replace: true });
+          const returnPath =
+            typeof response.return_path === 'string' &&
+            response.return_path.startsWith('/') &&
+            !response.return_path.startsWith('//')
+              ? response.return_path
+              : '/home';
+          navigate(returnPath, { replace: true });
           return;
         }
         setStatus('success');
@@ -207,8 +218,29 @@ function SpaceOAuthCallbackContent() {
     const errorDescription = searchParams.get('error_description');
     const mode = searchParams.get('mode');
     const state = searchParams.get('state');
-    const workspaceUuid = searchParams.get('workspace_uuid');
-    const launchAssertion = searchParams.get('launch_assertion');
+    if (directLaunchFragmentRef.current === null) {
+      const fragmentParams = new URLSearchParams(
+        window.location.hash.startsWith('#')
+          ? window.location.hash.slice(1)
+          : window.location.hash,
+      );
+      directLaunchFragmentRef.current = {
+        workspaceUuid: fragmentParams.get('workspace_uuid'),
+        launchAssertion: fragmentParams.get('launch_assertion'),
+      };
+      if (window.location.hash) {
+        window.history.replaceState(
+          null,
+          '',
+          `${window.location.pathname}${window.location.search}`,
+        );
+      }
+    }
+    const workspaceUuid =
+      directLaunchFragmentRef.current.workspaceUuid ??
+      searchParams.get('workspace_uuid');
+    const launchAssertion =
+      directLaunchFragmentRef.current.launchAssertion;
 
     if (error) {
       setStatus('error');

web/tests/unit/space-launch-callback.test.mjs

@@ -0,0 +1,24 @@
+import assert from 'node:assert/strict';
+import fs from 'node:fs';
+import test from 'node:test';
+
+const source = fs.readFileSync(
+  new URL('../../src/app/auth/space/callback/page.tsx', import.meta.url),
+  'utf8',
+);
+
+test('direct launch assertion is fragment-only and removed before exchange', () => {
+  assert.doesNotMatch(source, /searchParams\.get\(['"]launch_assertion['"]\)/);
+  const readIndex = source.indexOf("fragmentParams.get('launch_assertion')");
+  const clearIndex = source.indexOf('window.history.replaceState');
+  const exchangeIndex = source.indexOf('handleOAuthCallback(', clearIndex);
+  assert.ok(readIndex >= 0, 'fragment assertion read is missing');
+  assert.ok(clearIndex > readIndex, 'URL fragment is not cleared after copying the assertion');
+  assert.ok(exchangeIndex > clearIndex, 'assertion exchange starts before the fragment is cleared');
+});
+
+test('direct launch honors only a local signed return path', () => {
+  assert.match(source, /response\.return_path\.startsWith\(['"]\/['"]\)/);
+  assert.match(source, /!response\.return_path\.startsWith\(['"]\/\/['"]\)/);
+  assert.match(source, /navigate\(returnPath, \{ replace: true \}\)/);
+});