feat: add server store role overrides

src/wf_mcp/broker/config.py

@@ -9,6 +9,7 @@ from wf_config.models import FilesystemStoreConfig, McpSourceConfig, ServerConfi
 
 from ..control import BrokerConfigFile, ConnectionConfigFile
 from ..models import BrokerConfig
+from .models import BrokerStoreRoots
 from ..runtime import McpRuntimePool, PersistentSessionFactory
 from ..sdk import McpSdkAdapter
 from ..source_registry import (
@@ -104,10 +105,32 @@ def load_broker_config(path: str | Path) -> BrokerConfig:
     return BrokerConfigFile.model_validate(data).to_runtime(config_path=config_path)
 
 
+def _filesystem_store_root(store: object, *, role: str) -> Path:
+    if not isinstance(store, FilesystemStoreConfig):
+        raise ValueError(f"MCP-backed workflow server requires filesystem {role} store")
+    return store.root
+
+
 def broker_config_from_workflow_config(config: WorkflowConfigFile) -> BrokerConfig:
     """Create MCP broker runtime config from neutral workflow server config."""
     return BrokerConfig(
         store_root=config.server.store.root,
+        store_roots=BrokerStoreRoots(
+            default_root=config.server.store.root,
+            workflow_root=_filesystem_store_root(
+                config.server.workflow_store,
+                role="workflow",
+            ),
+            auth_root=_filesystem_store_root(config.server.auth_store, role="auth"),
+            source_registry_root=_filesystem_store_root(
+                config.server.source_registry_store,
+                role="source_registry",
+            ),
+            catalog_cache_root=_filesystem_store_root(
+                config.server.catalog_cache_store,
+                role="catalog_cache",
+            ),
+        ),
         connections=[
             workflow_mcp_source_to_connection_config(source)
             for source in config.server.sources
@@ -139,9 +162,13 @@ def migrate_broker_config_file(path: str | Path) -> WorkflowConfigFile:
 def build_service_from_config(config: BrokerConfig) -> WfMcpService:
     """Create a broker service with SDK adapters for configured connections."""
     runtime_factory = PersistentSessionFactory()
-    workflow_stores = file_workflow_stores(config.store_root)
+    store_roots = config.store_roots or BrokerStoreRoots.from_default(config.store_root)
+    workflow_stores = file_workflow_stores(store_roots.workflow_root)
+    # FileStore still owns both auth files and catalog snapshots. Role roots are
+    # carried separately so a later FileStore split can move catalog_cache without a
+    # config migration.
     service = WfMcpService(
-        store=FileStore(config.store_root),
+        store=FileStore(store_roots.auth_root),
         artifact_store=workflow_stores.artifact_store,
         draft_workspace_store=workflow_stores.draft_workspace_store,
         run_store=workflow_stores.run_store,
@@ -150,7 +177,7 @@ def build_service_from_config(config: BrokerConfig) -> WfMcpService:
         # across sequential workflow nodes.
         tool_executor=McpRuntimePool(runtime_factory.create),
     )
-    source_registry_store = FileSourceRegistryStore(config.store_root)
+    source_registry_store = FileSourceRegistryStore(store_roots.source_registry_root)
     service.sync_connections_from_config(
         config,
         source_registry_store=source_registry_store,

src/wf_mcp/broker/models.py

@@ -7,6 +7,32 @@ from typing import Any, Literal
 SourceConfigOwnership = Literal["locked", "seed"]
 
 
+@dataclass(frozen=True, slots=True)
+class BrokerStoreRoots:
+    """Resolved filesystem roots for MCP compatibility stores.
+
+    `default_root` preserves legacy `store_root` behavior. Role roots let
+    neutral config split workflow records, auth, desired source registry, and
+    catalog/cache storage without changing legacy config files.
+    """
+
+    default_root: Path
+    workflow_root: Path
+    auth_root: Path
+    source_registry_root: Path
+    catalog_cache_root: Path
+
+    @classmethod
+    def from_default(cls, root: Path) -> BrokerStoreRoots:
+        return cls(
+            default_root=root,
+            workflow_root=root,
+            auth_root=root,
+            source_registry_root=root,
+            catalog_cache_root=root,
+        )
+
+
 @dataclass(slots=True)
 class ConnectionConfig:
     id: str
@@ -21,10 +47,16 @@ class ConnectionConfig:
 class BrokerConfig:
     store_root: Path
     connections: list[ConnectionConfig] = field(default_factory=list)
+    store_roots: BrokerStoreRoots | None = None
+
+    def __post_init__(self) -> None:
+        if self.store_roots is None:
+            self.store_roots = BrokerStoreRoots.from_default(self.store_root)
 
 
 __all__ = [
     "BrokerConfig",
+    "BrokerStoreRoots",
     "ConnectionConfig",
     "SourceConfigOwnership",
 ]

src/wf_mcp/broker/server.py

@@ -107,10 +107,13 @@ def workflow_server_from_service(
 def build_workflow_server_from_config(config: BrokerConfig) -> WorkflowServer:
     """Build a neutral WorkflowServer backed by MCP broker runtime services."""
     service = build_service_from_config(config)
+    assert config.store_roots is not None
     return workflow_server_from_service(
         service,
         config=config,
-        source_registry_store=FileSourceRegistryStore(config.store_root),
+        source_registry_store=FileSourceRegistryStore(
+            config.store_roots.source_registry_root
+        ),
     )