feat: prefer stateful runtime for mcp content access

src/wf_mcp/broker/config.py

@@ -168,6 +168,10 @@ def build_service_from_config(config: BrokerConfig) -> WfMcpService:
     # focused services receive role-specific stores.
     auth_store = FileAuthStore(store_roots.auth_root)
     catalog_store = FileCatalogStore(store_roots.catalog_cache_root)
+    # Discovery can use short-lived SDK sessions. Workflow execution needs
+    # a persistent runtime so stateful MCP servers keep session/page state
+    # across sequential workflow nodes.
+    runtime_pool = McpRuntimePool(runtime_factory.create)
     service = WfMcpService(
         store=FileStore(store_roots.auth_root),
         auth_store=auth_store,
@@ -178,7 +182,8 @@ def build_service_from_config(config: BrokerConfig) -> WfMcpService:
         # Discovery can use short-lived SDK sessions. Workflow execution needs
         # a persistent runtime so stateful MCP servers keep session/page state
         # across sequential workflow nodes.
-        tool_executor=McpRuntimePool(runtime_factory.create),
+        tool_executor=runtime_pool,
+        stateful_runtime=runtime_pool,
     )
     source_registry_store = FileSourceRegistryStore(store_roots.source_registry_root)
     service.sync_connections_from_config(

src/wf_mcp/broker/service/core.py

@@ -26,7 +26,7 @@ from wf_sources_mcp.catalog import (
     CatalogPromptEntry,
     CatalogResourceEntry,
 )
-from wf_sources_mcp.sdk import BackendAdapter, ToolExecutor
+from wf_sources_mcp.sdk import BackendAdapter, StatefulMcpRuntime, ToolExecutor
 from wf_sources_mcp.source_registry import SourceRegistryStore
 from wf_sources_mcp.storage import AuthStore, CatalogStore, Store
 
@@ -68,6 +68,7 @@ class WfMcpService:
     draft_workspace_store: DraftWorkspaceStore | None = None
     run_store: RunStore | None = None
     tool_executor: ToolExecutor | None = None
+    stateful_runtime: StatefulMcpRuntime | None = None
     events: BrokerEventRecorder = field(init=False)
     connection_service: ConnectionService = field(init=False)
     upstream: UpstreamTransportService = field(init=False)
@@ -91,6 +92,7 @@ class WfMcpService:
             catalog_store=catalog_store,
             event_sink=self.events.record_event,
             tool_executor=self.tool_executor,
+            stateful_runtime=self.stateful_runtime,
         )
         self.source_catalog = SourceCatalogService(
             store=catalog_store,

src/wf_mcp/broker/service/upstream_transport.py

@@ -28,10 +28,9 @@ from wf_mcp.shared.errors import error_payload
 from wf_sources_mcp.auth import AuthRecord, connection_auth_diagnostic
 from wf_sources_mcp.catalog.models import CatalogSnapshot
 from wf_sources_mcp.connections import (
-    McpSourceConnection,
     mcp_source_connection_from_connection_config,
 )
-from wf_sources_mcp.sdk import BackendAdapter, ToolExecutor
+from wf_sources_mcp.sdk import BackendAdapter, StatefulMcpRuntime, ToolExecutor
 from wf_sources_mcp.storage import AuthStore, CatalogStore
 
 from .adapters import require_adapter
@@ -53,6 +52,7 @@ class UpstreamTransportService:
     event_sink: EventSink
     adapters: dict[str, BackendAdapter] = field(default_factory=dict)
     tool_executor: ToolExecutor | None = None
+    stateful_runtime: StatefulMcpRuntime | None = None
 
     def register_adapter(self, server: str, adapter: BackendAdapter) -> None:
         self.adapters[server] = adapter
@@ -103,7 +103,6 @@ class UpstreamTransportService:
         qualified_name: str,
         uri: str,
     ) -> dict[str, Any]:
-        adapter = require_adapter(connection, self.adapters)
         auth = self.load_connection_auth(connection)
         # Compatibility boundary: broker callers still pass ConnectionConfig.
         source_connection = mcp_source_connection_from_connection_config(connection)
@@ -115,7 +114,15 @@ class UpstreamTransportService:
                 payload={"uri": uri},
             )
         )
-        result = await adapter.read_resource(source_connection, auth, uri)
+        if self.stateful_runtime is not None:
+            result = await self.stateful_runtime.read_resource(
+                source_connection,
+                auth,
+                uri,
+            )
+        else:
+            adapter = require_adapter(connection, self.adapters)
+            result = await adapter.read_resource(source_connection, auth, uri)
         self.event_sink(
             make_event(
                 "resource_read_completed",
@@ -133,7 +140,6 @@ class UpstreamTransportService:
         local_name: str,
         arguments: dict[str, str] | None = None,
     ) -> dict[str, Any]:
-        adapter = require_adapter(connection, self.adapters)
         auth = self.load_connection_auth(connection)
         # Compatibility boundary: broker callers still pass ConnectionConfig.
         source_connection = mcp_source_connection_from_connection_config(connection)
@@ -145,7 +151,16 @@ class UpstreamTransportService:
                 payload={"argument_keys": sorted((arguments or {}).keys())},
             )
         )
-        result = await adapter.get_prompt(source_connection, auth, local_name, arguments)
+        if self.stateful_runtime is not None:
+            result = await self.stateful_runtime.get_prompt(
+                source_connection,
+                auth,
+                local_name,
+                arguments,
+            )
+        else:
+            adapter = require_adapter(connection, self.adapters)
+            result = await adapter.get_prompt(source_connection, auth, local_name, arguments)
         self.event_sink(
             make_event(
                 "prompt_get_completed",