diff --git a/cmd/core-agent/main.go b/cmd/core-agent/main.go
index 25a6eca..34be9a4 100644
--- a/cmd/core-agent/main.go
+++ b/cmd/core-agent/main.go
@@ -302,9 +302,9 @@ func main() {
 	})
 
 	// Retrieve service instances from conclave for MCP tool registration
-	agenticSvc := core.ConfigGet[*agentic.PrepSubsystem](c.Config(), "agentic.instance")
-	monitorSvc := core.ConfigGet[*monitor.Subsystem](c.Config(), "monitor.instance")
-	brainSvc := core.ConfigGet[*brain.DirectSubsystem](c.Config(), "brain.instance")
+	agenticSvc, _ := core.ServiceFor[*agentic.PrepSubsystem](c, "agentic")
+	monitorSvc, _ := core.ServiceFor[*monitor.Subsystem](c, "monitor")
+	brainSvc, _ := core.ServiceFor[*brain.DirectSubsystem](c, "brain")
 
 	// Process service (lifecycle management)
 	procFactory := process.NewService(process.Options{})
diff --git a/pkg/agentic/prep.go b/pkg/agentic/prep.go
index 48cfe0d..9659db7 100644
--- a/pkg/agentic/prep.go
+++ b/pkg/agentic/prep.go
@@ -87,6 +87,17 @@ func (s *PrepSubsystem) SetCore(c *core.Core) {
 	s.core = c
 }
 
+// OnStartup implements core.Startable — starts the queue runner.
+func (s *PrepSubsystem) OnStartup(ctx context.Context) error {
+	s.StartRunner()
+	return nil
+}
+
+// OnShutdown implements core.Stoppable — freezes the queue.
+func (s *PrepSubsystem) OnShutdown(ctx context.Context) error {
+	s.frozen = true
+	return nil
+}
 
 func envOr(key, fallback string) string {
 	if v := core.Env(key); v != "" {
diff --git a/pkg/agentic/register.go b/pkg/agentic/register.go
index b428e2a..4fabe2a 100644
--- a/pkg/agentic/register.go
+++ b/pkg/agentic/register.go
@@ -7,16 +7,8 @@ import (
 )
 
 // Register is the service factory for core.WithService.
-// It creates the PrepSubsystem, wires Core, registers lifecycle hooks,
-// and registers IPC handlers — all during Core construction.
-//
-//	core.New(
-//	    core.WithService(agentic.Register),
-//	)
-// Register is the service factory for core.WithService.
-// It creates the PrepSubsystem, wires Core, registers lifecycle hooks,
-// and registers IPC handlers — all during Core construction.
-// The PrepSubsystem instance is stored in Config for retrieval by MCP.
+// Creates the PrepSubsystem, registers it via RegisterService (auto-discovers
+// Startable/Stoppable), loads config, and wires IPC handlers.
 //
 //	core.New(
 //	    core.WithService(agentic.Register),
@@ -31,21 +23,10 @@ func Register(c *core.Core) core.Result {
 	c.Config().Set("agents.rates", cfg.Rates)
 	c.Config().Set("agents.dispatch", cfg.Dispatch)
 
-	c.Service("agentic", core.Service{
-		OnStart: func() core.Result {
-			prep.StartRunner()
-			return core.Result{OK: true}
-		},
-		OnStop: func() core.Result {
-			prep.frozen = true
-			return core.Result{OK: true}
-		},
-	})
+	// Register instance — lifecycle hooks wired via Startable/Stoppable if implemented
+	c.RegisterService("agentic", prep)
 
 	RegisterHandlers(c, prep)
 
-	// Store instance for MCP tool registration
-	c.Config().Set("agentic.instance", prep)
-
-	return core.Result{OK: true}
+	return core.Result{Value: prep, OK: true}
 }
diff --git a/pkg/brain/register.go b/pkg/brain/register.go
index c4f84b2..fe168a5 100644
--- a/pkg/brain/register.go
+++ b/pkg/brain/register.go
@@ -7,18 +7,13 @@ import (
 )
 
 // Register is the service factory for core.WithService.
-// Brain has no lifecycle hooks — it's a stateless API proxy.
+// Brain is a stateless API proxy — no lifecycle hooks.
 //
 //	core.New(
 //	    core.WithService(brain.Register),
 //	)
 func Register(c *core.Core) core.Result {
 	brn := NewDirect()
-
-	c.Service("brain", core.Service{})
-
-	// Store instance for MCP tool registration
-	c.Config().Set("brain.instance", brn)
-
-	return core.Result{OK: true}
+	c.RegisterService("brain", brn)
+	return core.Result{Value: brn, OK: true}
 }
diff --git a/pkg/monitor/monitor.go b/pkg/monitor/monitor.go
index 20806f3..b40237b 100644
--- a/pkg/monitor/monitor.go
+++ b/pkg/monitor/monitor.go
@@ -251,6 +251,17 @@ func (m *Subsystem) Start(ctx context.Context) {
 	}()
 }
 
+// OnStartup implements core.Startable — starts the monitoring loop.
+func (m *Subsystem) OnStartup(ctx context.Context) error {
+	m.Start(ctx)
+	return nil
+}
+
+// OnShutdown implements core.Stoppable — stops the monitoring loop.
+func (m *Subsystem) OnShutdown(ctx context.Context) error {
+	return m.Shutdown(ctx)
+}
+
 // Shutdown stops the monitoring loop and waits for it to exit.
 //
 //	_ = mon.Shutdown(ctx)
diff --git a/pkg/monitor/register.go b/pkg/monitor/register.go
index 53cc309..1f0e838 100644
--- a/pkg/monitor/register.go
+++ b/pkg/monitor/register.go
@@ -8,8 +8,8 @@ import (
 )
 
 // Register is the service factory for core.WithService.
-// It creates the monitor subsystem, wires Core for IPC,
-// and registers lifecycle hooks.
+// Creates the monitor subsystem, registers via RegisterService,
+// and wires IPC handlers for agent lifecycle events.
 //
 //	core.New(
 //	    core.WithService(monitor.Register),
@@ -18,12 +18,7 @@ func Register(c *core.Core) core.Result {
 	mon := New()
 	mon.core = c
 
-	c.Service("monitor", core.Service{
-		OnStart: func() core.Result {
-			mon.Start(c.Context())
-			return core.Result{OK: true}
-		},
-	})
+	c.RegisterService("monitor", mon)
 
 	// Register IPC handler for agent lifecycle events
 	c.RegisterAction(func(c *core.Core, msg core.Message) core.Result {
@@ -36,8 +31,5 @@ func Register(c *core.Core) core.Result {
 		return core.Result{OK: true}
 	})
 
-	// Store instance for MCP tool registration
-	c.Config().Set("monitor.instance", mon)
-
-	return core.Result{OK: true}
+	return core.Result{Value: mon, OK: true}
 }