fix: load mcp auth at tool call time

src/wf_mcp/broker/discovery.py

@@ -34,6 +34,7 @@ def specs_from_discovered_tools(
     *,
     connection: ConnectionConfig,
     auth: AuthRecord | None,
+    auth_loader: Callable[[], AuthRecord | None] | None = None,
     executor: ToolExecutor,
     tools: list[DiscoveredTool],
     emit_event: Callable[[McpEvent], None] | None = None,
@@ -50,6 +51,7 @@ def specs_from_discovered_tools(
     return source_specs_from_discovered_tools(
         connection=source_connection,
         auth=auth,
+        auth_loader=auth_loader,
         executor=executor,
         tools=tools,
         emit_event=emit_tool_event if emit_event is not None else None,

src/wf_mcp/broker/service/upstream_transport.py

@@ -273,6 +273,7 @@ class UpstreamTransportService:
             specs = specs_from_discovered_tools(
                 connection=connection,
                 auth=auth,
+                auth_loader=lambda: self.load_connection_auth(connection),
                 executor=self.tool_executor_for(connection),
                 tools=capabilities.tools,
                 emit_event=self.event_sink,