diff --git a/cmd/opampsupervisor/e2e_test.go b/cmd/opampsupervisor/e2e_test.go
index 96935b4bd0d0..b4f80e9624c8 100644
--- a/cmd/opampsupervisor/e2e_test.go
+++ b/cmd/opampsupervisor/e2e_test.go
@@ -64,7 +64,7 @@ func (tl testLogger) Errorf(_ context.Context, format string, args ...any) {
 	tl.t.Logf(format, args...)
 }
 
-func defaultConnectingHandler(connectionCallbacks server.ConnectionCallbacksStruct) func(request *http.Request) types.ConnectionResponse {
+func defaultConnectingHandler(connectionCallbacks types.ConnectionCallbacks) func(request *http.Request) types.ConnectionResponse {
 	return func(_ *http.Request) types.ConnectionResponse {
 		return types.ConnectionResponse{
 			Accept:              true,
@@ -73,11 +73,11 @@ func defaultConnectingHandler(connectionCallbacks server.ConnectionCallbacksStru
 	}
 }
 
-// onConnectingFuncFactory is a function that will be given to server.CallbacksStruct as
+// onConnectingFuncFactory is a function that will be given to types.ConnectionCallbacks as
 // OnConnectingFunc. This allows changing the ConnectionCallbacks both from the newOpAMPServer
 // caller and inside of newOpAMP Server, and for custom implementations of the value for `Accept`
 // in types.ConnectionResponse.
-type onConnectingFuncFactory func(connectionCallbacks server.ConnectionCallbacksStruct) func(request *http.Request) types.ConnectionResponse
+type onConnectingFuncFactory func(connectionCallbacks types.ConnectionCallbacks) func(request *http.Request) types.ConnectionResponse
 
 type testingOpAMPServer struct {
 	addr                string
@@ -87,20 +87,20 @@ type testingOpAMPServer struct {
 	shutdown            func()
 }
 
-func newOpAMPServer(t *testing.T, connectingCallback onConnectingFuncFactory, callbacks server.ConnectionCallbacksStruct) *testingOpAMPServer {
+func newOpAMPServer(t *testing.T, connectingCallback onConnectingFuncFactory, callbacks types.ConnectionCallbacks) *testingOpAMPServer {
 	s := newUnstartedOpAMPServer(t, connectingCallback, callbacks)
 	s.start()
 	return s
 }
 
-func newUnstartedOpAMPServer(t *testing.T, connectingCallback onConnectingFuncFactory, callbacks server.ConnectionCallbacksStruct) *testingOpAMPServer {
+func newUnstartedOpAMPServer(t *testing.T, connectingCallback onConnectingFuncFactory, callbacks types.ConnectionCallbacks) *testingOpAMPServer {
 	var agentConn atomic.Value
 	var isAgentConnected atomic.Bool
 	var didShutdown atomic.Bool
 	connectedChan := make(chan bool)
 	s := server.New(testLogger{t: t})
-	onConnectedFunc := callbacks.OnConnectedFunc
-	callbacks.OnConnectedFunc = func(ctx context.Context, conn types.Connection) {
+	onConnectedFunc := callbacks.OnConnected
+	callbacks.OnConnected = func(ctx context.Context, conn types.Connection) {
 		if onConnectedFunc != nil {
 			onConnectedFunc(ctx, conn)
 		}
@@ -108,8 +108,8 @@ func newUnstartedOpAMPServer(t *testing.T, connectingCallback onConnectingFuncFa
 		isAgentConnected.Store(true)
 		connectedChan <- true
 	}
-	onConnectionCloseFunc := callbacks.OnConnectionCloseFunc
-	callbacks.OnConnectionCloseFunc = func(conn types.Connection) {
+	onConnectionCloseFunc := callbacks.OnConnectionClose
+	callbacks.OnConnectionClose = func(conn types.Connection) {
 		isAgentConnected.Store(false)
 		connectedChan <- false
 		if onConnectionCloseFunc != nil {
@@ -117,8 +117,8 @@ func newUnstartedOpAMPServer(t *testing.T, connectingCallback onConnectingFuncFa
 		}
 	}
 	handler, _, err := s.Attach(server.Settings{
-		Callbacks: server.CallbacksStruct{
-			OnConnectingFunc: connectingCallback(callbacks),
+		Callbacks: types.Callbacks{
+			OnConnecting: connectingCallback(callbacks),
 		},
 	})
 	require.NoError(t, err)
@@ -211,8 +211,8 @@ func TestSupervisorStartsCollectorWithRemoteConfig(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
@@ -287,8 +287,8 @@ func TestSupervisorStartsCollectorWithNoOpAMPServer(t *testing.T) {
 	require.NoError(t, os.WriteFile(remoteConfigFilePath, marshalledRemoteConfig, 0o600))
 
 	connected := atomic.Bool{}
-	server := newUnstartedOpAMPServer(t, defaultConnectingHandler, server.ConnectionCallbacksStruct{
-		OnConnectedFunc: func(ctx context.Context, conn types.Connection) {
+	server := newUnstartedOpAMPServer(t, defaultConnectingHandler, types.ConnectionCallbacks{
+		OnConnected: func(ctx context.Context, conn types.Connection) {
 			connected.Store(true)
 		},
 	})
@@ -331,19 +331,20 @@ func TestSupervisorStartsWithNoOpAMPServer(t *testing.T) {
 
 	configuredChan := make(chan struct{})
 	connected := atomic.Bool{}
-	server := newUnstartedOpAMPServer(t, defaultConnectingHandler, server.ConnectionCallbacksStruct{
-		OnConnectedFunc: func(ctx context.Context, conn types.Connection) {
-			connected.Store(true)
-		},
-		OnMessageFunc: func(ctx context.Context, conn types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
-			lastCfgHash := message.GetRemoteConfigStatus().GetLastRemoteConfigHash()
-			if bytes.Equal(lastCfgHash, hash) {
-				close(configuredChan)
-			}
+	server := newUnstartedOpAMPServer(t, defaultConnectingHandler,
+		types.ConnectionCallbacks{
+			OnConnected: func(ctx context.Context, conn types.Connection) {
+				connected.Store(true)
+			},
+			OnMessage: func(ctx context.Context, conn types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+				lastCfgHash := message.GetRemoteConfigStatus().GetLastRemoteConfigHash()
+				if bytes.Equal(lastCfgHash, hash) {
+					close(configuredChan)
+				}
 
-			return &protobufs.ServerToAgent{}
-		},
-	})
+				return &protobufs.ServerToAgent{}
+			},
+		})
 	defer server.shutdown()
 
 	// The supervisor is started without a running OpAMP server.
@@ -415,8 +416,8 @@ func TestSupervisorRestartsCollectorAfterBadConfig(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.Health != nil {
 					healthReport.Store(message.Health)
 				}
@@ -501,8 +502,8 @@ func TestSupervisorConfiguresCapabilities(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				capabilities.Store(message.Capabilities)
 
 				return &protobufs.ServerToAgent{}
@@ -556,8 +557,8 @@ func TestSupervisorBootstrapsCollector(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.AgentDescription != nil {
 					agentDescription.Store(message.AgentDescription)
 				}
@@ -602,8 +603,8 @@ func TestSupervisorReportsEffectiveConfig(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
@@ -713,8 +714,8 @@ func TestSupervisorAgentDescriptionConfigApplies(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.AgentDescription != nil {
 					select {
 					case agentDescMessageChan <- message:
@@ -866,8 +867,8 @@ func TestSupervisorRestartCommand(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.Health != nil {
 					healthReport.Store(message.Health)
 				}
@@ -948,7 +949,7 @@ func TestSupervisorOpAMPConnectionSettings(t *testing.T) {
 	initialServer := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{})
+		types.ConnectionCallbacks{})
 
 	s := newSupervisor(t, "accepts_conn", map[string]string{"url": initialServer.addr})
 
@@ -960,11 +961,11 @@ func TestSupervisorOpAMPConnectionSettings(t *testing.T) {
 	newServer := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnConnectedFunc: func(_ context.Context, _ types.Connection) {
+		types.ConnectionCallbacks{
+			OnConnected: func(_ context.Context, _ types.Connection) {
 				connectedToNewServer.Store(true)
 			},
-			OnMessageFunc: func(_ context.Context, _ types.Connection, _ *protobufs.AgentToServer) *protobufs.ServerToAgent {
+			OnMessage: func(_ context.Context, _ types.Connection, _ *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				return &protobufs.ServerToAgent{}
 			},
 		})
@@ -999,8 +1000,8 @@ func TestSupervisorRestartsWithLastReceivedConfig(t *testing.T) {
 	initialServer := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
@@ -1043,8 +1044,8 @@ func TestSupervisorRestartsWithLastReceivedConfig(t *testing.T) {
 	newServer := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
@@ -1087,8 +1088,8 @@ func TestSupervisorPersistsInstanceID(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				select {
 				case agentIDChan <- message.InstanceUid:
 				default:
@@ -1163,8 +1164,8 @@ func TestSupervisorPersistsNewInstanceID(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				select {
 				case agentIDChan <- message.InstanceUid:
 				default:
@@ -1242,7 +1243,7 @@ func TestSupervisorWritesAgentFilesToStorageDir(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{},
+		types.ConnectionCallbacks{},
 	)
 
 	s := newSupervisor(t, "basic", map[string]string{
@@ -1270,8 +1271,8 @@ func TestSupervisorStopsAgentProcessWithEmptyConfigMap(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
@@ -1386,8 +1387,8 @@ func TestSupervisorLogging(t *testing.T) {
 	require.NoError(t, os.WriteFile(remoteCfgFilePath, marshalledRemoteCfg, 0o600))
 
 	connected := atomic.Bool{}
-	server := newUnstartedOpAMPServer(t, defaultConnectingHandler, server.ConnectionCallbacksStruct{
-		OnConnectedFunc: func(ctx context.Context, conn types.Connection) {
+	server := newUnstartedOpAMPServer(t, defaultConnectingHandler, types.ConnectionCallbacks{
+		OnConnected: func(ctx context.Context, conn types.Connection) {
 			connected.Store(true)
 		},
 	})
@@ -1449,8 +1450,8 @@ func TestSupervisorRemoteConfigApplyStatus(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
@@ -1586,8 +1587,8 @@ func TestSupervisorOpAmpServerPort(t *testing.T) {
 	server := newOpAMPServer(
 		t,
 		defaultConnectingHandler,
-		server.ConnectionCallbacksStruct{
-			OnMessageFunc: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
+		types.ConnectionCallbacks{
+			OnMessage: func(_ context.Context, _ types.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
 				if message.EffectiveConfig != nil {
 					config := message.EffectiveConfig.ConfigMap.ConfigMap[""]
 					if config != nil {
diff --git a/cmd/opampsupervisor/go.mod b/cmd/opampsupervisor/go.mod
index f81caa637fb0..01f95769086e 100644
--- a/cmd/opampsupervisor/go.mod
+++ b/cmd/opampsupervisor/go.mod
@@ -10,7 +10,7 @@ require (
 	github.com/knadh/koanf/providers/file v1.1.2
 	github.com/knadh/koanf/providers/rawbytes v0.1.0
 	github.com/knadh/koanf/v2 v2.1.2
-	github.com/open-telemetry/opamp-go v0.17.0
+	github.com/open-telemetry/opamp-go v0.18.0
 	github.com/stretchr/testify v1.10.0
 	go.opentelemetry.io/collector/config/configopaque v1.23.0
 	go.opentelemetry.io/collector/config/configtls v1.23.0
@@ -29,7 +29,6 @@ require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/fsnotify/fsnotify v1.8.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.2.1 // indirect
-	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/gorilla/websocket v1.5.3 // indirect
 	github.com/knadh/koanf/providers/confmap v0.1.0 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
diff --git a/cmd/opampsupervisor/go.sum b/cmd/opampsupervisor/go.sum
index 11ed3daec6fe..df86d5e3bebd 100644
--- a/cmd/opampsupervisor/go.sum
+++ b/cmd/opampsupervisor/go.sum
@@ -32,12 +32,14 @@ github.com/mitchellh/copystructure v1.2.0 h1:vpKXTN4ewci03Vljg/q9QvCGUDttBOGBIa1
 github.com/mitchellh/copystructure v1.2.0/go.mod h1:qLl+cE2AmVv+CoeAwDPye/v+N2HKCj9FbZEVFJRxO9s=
 github.com/mitchellh/reflectwalk v1.0.2 h1:G2LzWKi524PWgd3mLHV8Y5k7s6XUvT0Gef6zxSIeXaQ=
 github.com/mitchellh/reflectwalk v1.0.2/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
-github.com/open-telemetry/opamp-go v0.17.0 h1:3R4+B/6Sy8mknLBbzO3gqloqwTT02rCSRcr4ac2B124=
-github.com/open-telemetry/opamp-go v0.17.0/go.mod h1:SGDhUoAx7uGutO4ENNMQla/tiSujxgZmMPJXIOPGBdk=
+github.com/open-telemetry/opamp-go v0.18.0 h1:sNHsrBvGU2CMxCB1TRJXncDARrmxDEebx8dsEIawqA4=
+github.com/open-telemetry/opamp-go v0.18.0/go.mod h1:9/1G6T5dnJz4cJtoYSr6AX18kHdOxnxxETJPZSHyEUg=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
 github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
+github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 go.opentelemetry.io/collector/config/configopaque v1.23.0 h1:SEnEzOHufGc4KGOjQq8zKIQuDBmRFl9ncZ3qs1SRpJk=
diff --git a/cmd/opampsupervisor/supervisor/server.go b/cmd/opampsupervisor/supervisor/server.go
index cd54f96336eb..4ecfd9afa617 100644
--- a/cmd/opampsupervisor/supervisor/server.go
+++ b/cmd/opampsupervisor/supervisor/server.go
@@ -13,24 +13,26 @@ import (
 )
 
 type flattenedSettings struct {
-	onMessageFunc         func(conn serverTypes.Connection, message *protobufs.AgentToServer)
-	onConnectingFunc      func(request *http.Request) (shouldConnect bool, rejectStatusCode int)
-	onConnectionCloseFunc func(conn serverTypes.Connection)
-	endpoint              string
+	onMessage         func(conn serverTypes.Connection, message *protobufs.AgentToServer)
+	onConnecting      func(request *http.Request) (shouldConnect bool, rejectStatusCode int)
+	onConnectionClose func(conn serverTypes.Connection)
+	endpoint          string
 }
 
 func (fs flattenedSettings) toServerSettings() server.StartSettings {
 	return server.StartSettings{
 		Settings: server.Settings{
-			Callbacks: fs,
+			Callbacks: serverTypes.Callbacks{
+				OnConnecting: fs.OnConnecting,
+			},
 		},
 		ListenEndpoint: fs.endpoint,
 	}
 }
 
 func (fs flattenedSettings) OnConnecting(request *http.Request) serverTypes.ConnectionResponse {
-	if fs.onConnectingFunc != nil {
-		shouldConnect, rejectStatusCode := fs.onConnectingFunc(request)
+	if fs.onConnecting != nil {
+		shouldConnect, rejectStatusCode := fs.onConnecting(request)
 		if !shouldConnect {
 			return serverTypes.ConnectionResponse{
 				Accept:         false,
@@ -40,23 +42,25 @@ func (fs flattenedSettings) OnConnecting(request *http.Request) serverTypes.Conn
 	}
 
 	return serverTypes.ConnectionResponse{
-		Accept:              true,
-		ConnectionCallbacks: fs,
+		Accept: true,
+		ConnectionCallbacks: serverTypes.ConnectionCallbacks{
+			OnMessage: fs.OnMessage,
+		},
 	}
 }
 
 func (fs flattenedSettings) OnConnected(_ context.Context, _ serverTypes.Connection) {}
 
 func (fs flattenedSettings) OnMessage(_ context.Context, conn serverTypes.Connection, message *protobufs.AgentToServer) *protobufs.ServerToAgent {
-	if fs.onMessageFunc != nil {
-		fs.onMessageFunc(conn, message)
+	if fs.onMessage != nil {
+		fs.onMessage(conn, message)
 	}
 
 	return &protobufs.ServerToAgent{}
 }
 
 func (fs flattenedSettings) OnConnectionClose(conn serverTypes.Connection) {
-	if fs.onConnectionCloseFunc != nil {
-		fs.onConnectionCloseFunc(conn)
+	if fs.onConnectionClose != nil {
+		fs.onConnectionClose(conn)
 	}
 }
diff --git a/cmd/opampsupervisor/supervisor/server_test.go b/cmd/opampsupervisor/supervisor/server_test.go
index e35c11ab186e..e4272270300a 100644
--- a/cmd/opampsupervisor/supervisor/server_test.go
+++ b/cmd/opampsupervisor/supervisor/server_test.go
@@ -28,7 +28,7 @@ func Test_flattenedSettings_OnConnecting(t *testing.T) {
 	t.Run("accept connection", func(t *testing.T) {
 		onConnectingFuncCalled := false
 		fs := flattenedSettings{
-			onConnectingFunc: func(_ *http.Request) (shouldConnect bool, rejectStatusCode int) {
+			onConnecting: func(_ *http.Request) (shouldConnect bool, rejectStatusCode int) {
 				onConnectingFuncCalled = true
 				return true, 0
 			},
@@ -43,7 +43,7 @@ func Test_flattenedSettings_OnConnecting(t *testing.T) {
 	t.Run("do not accept connection", func(t *testing.T) {
 		onConnectingFuncCalled := false
 		fs := flattenedSettings{
-			onConnectingFunc: func(_ *http.Request) (shouldConnect bool, rejectStatusCode int) {
+			onConnecting: func(_ *http.Request) (shouldConnect bool, rejectStatusCode int) {
 				onConnectingFuncCalled = true
 				return false, 500
 			},
@@ -60,7 +60,7 @@ func Test_flattenedSettings_OnConnecting(t *testing.T) {
 func Test_flattenedSettings_OnMessage(t *testing.T) {
 	onMessageFuncCalled := false
 	fs := flattenedSettings{
-		onMessageFunc: func(_ serverTypes.Connection, _ *protobufs.AgentToServer) {
+		onMessage: func(_ serverTypes.Connection, _ *protobufs.AgentToServer) {
 			onMessageFuncCalled = true
 		},
 	}
@@ -74,7 +74,7 @@ func Test_flattenedSettings_OnMessage(t *testing.T) {
 func Test_flattenedSettings_OnConnectionClose(t *testing.T) {
 	onConnectionCloseFuncCalled := false
 	fs := flattenedSettings{
-		onConnectionCloseFunc: func(_ serverTypes.Connection) {
+		onConnectionClose: func(_ serverTypes.Connection) {
 			onConnectionCloseFuncCalled = true
 		},
 	}
diff --git a/cmd/opampsupervisor/supervisor/supervisor.go b/cmd/opampsupervisor/supervisor/supervisor.go
index 4607aa6d5958..894854273c6a 100644
--- a/cmd/opampsupervisor/supervisor/supervisor.go
+++ b/cmd/opampsupervisor/supervisor/supervisor.go
@@ -305,11 +305,11 @@ func (s *Supervisor) getBootstrapInfo() (err error) {
 	// using the Collector's OpAMP extension.
 	err = srv.Start(flattenedSettings{
 		endpoint: fmt.Sprintf("localhost:%d", s.opampServerPort),
-		onConnectingFunc: func(_ *http.Request) (bool, int) {
+		onConnecting: func(_ *http.Request) (bool, int) {
 			connected.Store(true)
 			return true, http.StatusOK
 		},
-		onMessageFunc: func(_ serverTypes.Connection, message *protobufs.AgentToServer) {
+		onMessage: func(_ serverTypes.Connection, message *protobufs.AgentToServer) {
 			if message.AgentDescription != nil {
 				instanceIDSeen := false
 				s.setAgentDescription(message.AgentDescription)
@@ -415,33 +415,33 @@ func (s *Supervisor) startOpAMPClient() error {
 		Header:         s.config.Server.Headers,
 		TLSConfig:      tlsConfig,
 		InstanceUid:    types.InstanceUid(s.persistentState.InstanceID),
-		Callbacks: types.CallbacksStruct{
-			OnConnectFunc: func(_ context.Context) {
+		Callbacks: types.Callbacks{
+			OnConnect: func(_ context.Context) {
 				s.logger.Debug("Connected to the server.")
 			},
-			OnConnectFailedFunc: func(_ context.Context, err error) {
+			OnConnectFailed: func(_ context.Context, err error) {
 				s.logger.Error("Failed to connect to the server", zap.Error(err))
 			},
-			OnErrorFunc: func(_ context.Context, err *protobufs.ServerErrorResponse) {
+			OnError: func(_ context.Context, err *protobufs.ServerErrorResponse) {
 				s.logger.Error("Server returned an error response", zap.String("message", err.ErrorMessage))
 			},
-			OnMessageFunc: s.onMessage,
-			OnOpampConnectionSettingsFunc: func(ctx context.Context, settings *protobufs.OpAMPConnectionSettings) error {
+			OnMessage: s.onMessage,
+			OnOpampConnectionSettings: func(ctx context.Context, settings *protobufs.OpAMPConnectionSettings) error {
 				//nolint:errcheck
 				go s.onOpampConnectionSettings(ctx, settings)
 				return nil
 			},
-			OnCommandFunc: func(_ context.Context, command *protobufs.ServerToAgentCommand) error {
+			OnCommand: func(_ context.Context, command *protobufs.ServerToAgentCommand) error {
 				cmdType := command.GetType()
 				if *cmdType.Enum() == protobufs.CommandType_CommandType_Restart {
 					return s.handleRestartCommand()
 				}
 				return nil
 			},
-			SaveRemoteConfigStatusFunc: func(_ context.Context, _ *protobufs.RemoteConfigStatus) {
+			SaveRemoteConfigStatus: func(_ context.Context, _ *protobufs.RemoteConfigStatus) {
 				// TODO: https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/21079
 			},
-			GetEffectiveConfigFunc: func(_ context.Context) (*protobufs.EffectiveConfig, error) {
+			GetEffectiveConfig: func(_ context.Context) (*protobufs.EffectiveConfig, error) {
 				return s.createEffectiveConfigMsg(), nil
 			},
 		},
@@ -486,13 +486,13 @@ func (s *Supervisor) startOpAMPServer() error {
 
 	err = s.opampServer.Start(flattenedSettings{
 		endpoint: fmt.Sprintf("localhost:%d", s.opampServerPort),
-		onConnectingFunc: func(_ *http.Request) (bool, int) {
+		onConnecting: func(_ *http.Request) (bool, int) {
 			// Only allow one agent to be connected the this server at a time.
 			alreadyConnected := connected.Swap(true)
 			return !alreadyConnected, http.StatusConflict
 		},
-		onMessageFunc: s.handleAgentOpAMPMessage,
-		onConnectionCloseFunc: func(_ serverTypes.Connection) {
+		onMessage: s.handleAgentOpAMPMessage,
+		onConnectionClose: func(_ serverTypes.Connection) {
 			connected.Store(false)
 		},
 	}.toServerSettings())
diff --git a/extension/opampcustommessages/go.mod b/extension/opampcustommessages/go.mod
index ae570bbaf804..061532dd4151 100644
--- a/extension/opampcustommessages/go.mod
+++ b/extension/opampcustommessages/go.mod
@@ -2,6 +2,6 @@ module github.com/open-telemetry/opentelemetry-collector-contrib/extension/opamp
 
 go 1.22.0
 
-require github.com/open-telemetry/opamp-go v0.17.0
+require github.com/open-telemetry/opamp-go v0.18.0
 
-require google.golang.org/protobuf v1.34.2 // indirect
+require google.golang.org/protobuf v1.36.2 // indirect
diff --git a/extension/opampcustommessages/go.sum b/extension/opampcustommessages/go.sum
index 856df9d69ae9..f4989ff2145b 100644
--- a/extension/opampcustommessages/go.sum
+++ b/extension/opampcustommessages/go.sum
@@ -1,8 +1,6 @@
-github.com/google/go-cmp v0.5.6 h1:BKbKCqvP6I+rmFHt06ZmyQtvB8xAkWdhFyr0ZUNZcxQ=
-github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/open-telemetry/opamp-go v0.17.0 h1:3R4+B/6Sy8mknLBbzO3gqloqwTT02rCSRcr4ac2B124=
-github.com/open-telemetry/opamp-go v0.17.0/go.mod h1:SGDhUoAx7uGutO4ENNMQla/tiSujxgZmMPJXIOPGBdk=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-google.golang.org/protobuf v1.34.2 h1:6xV6lTsCfpGD21XK49h7MhtcApnLqkfYgPcdHftf6hg=
-google.golang.org/protobuf v1.34.2/go.mod h1:qYOHts0dSfpeUzUFpOMr/WGzszTmLH+DiWniOlNbLDw=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/open-telemetry/opamp-go v0.18.0 h1:sNHsrBvGU2CMxCB1TRJXncDARrmxDEebx8dsEIawqA4=
+github.com/open-telemetry/opamp-go v0.18.0/go.mod h1:9/1G6T5dnJz4cJtoYSr6AX18kHdOxnxxETJPZSHyEUg=
+google.golang.org/protobuf v1.36.2 h1:R8FeyR1/eLmkutZOM5CWghmo5itiG9z0ktFlTVLuTmU=
+google.golang.org/protobuf v1.36.2/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
diff --git a/extension/opampextension/go.mod b/extension/opampextension/go.mod
index 60dfa59f529c..4e3dc9bcba93 100644
--- a/extension/opampextension/go.mod
+++ b/extension/opampextension/go.mod
@@ -5,7 +5,7 @@ go 1.22.0
 require (
 	github.com/google/uuid v1.6.0
 	github.com/oklog/ulid/v2 v2.1.0
-	github.com/open-telemetry/opamp-go v0.17.0
+	github.com/open-telemetry/opamp-go v0.18.0
 	github.com/open-telemetry/opentelemetry-collector-contrib/extension/opampcustommessages v0.117.0
 	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/status v0.117.0
 	github.com/shirou/gopsutil/v4 v4.24.12
diff --git a/extension/opampextension/go.sum b/extension/opampextension/go.sum
index c5f0f975dfb9..ef065ce48345 100644
--- a/extension/opampextension/go.sum
+++ b/extension/opampextension/go.sum
@@ -46,8 +46,8 @@ github.com/mitchellh/reflectwalk v1.0.2 h1:G2LzWKi524PWgd3mLHV8Y5k7s6XUvT0Gef6zx
 github.com/mitchellh/reflectwalk v1.0.2/go.mod h1:mSTlrgnPZtwu0c4WaC2kGObEpuNDbx0jmZXqmk4esnw=
 github.com/oklog/ulid/v2 v2.1.0 h1:+9lhoxAP56we25tyYETBBY1YLA2SaoLvUFgrP2miPJU=
 github.com/oklog/ulid/v2 v2.1.0/go.mod h1:rcEKHmBBKfef9DhnvX7y1HZBYxjXb0cP5ExxNsTT1QQ=
-github.com/open-telemetry/opamp-go v0.17.0 h1:3R4+B/6Sy8mknLBbzO3gqloqwTT02rCSRcr4ac2B124=
-github.com/open-telemetry/opamp-go v0.17.0/go.mod h1:SGDhUoAx7uGutO4ENNMQla/tiSujxgZmMPJXIOPGBdk=
+github.com/open-telemetry/opamp-go v0.18.0 h1:sNHsrBvGU2CMxCB1TRJXncDARrmxDEebx8dsEIawqA4=
+github.com/open-telemetry/opamp-go v0.18.0/go.mod h1:9/1G6T5dnJz4cJtoYSr6AX18kHdOxnxxETJPZSHyEUg=
 github.com/pborman/getopt v0.0.0-20170112200414-7148bc3a4c30/go.mod h1:85jBQOZwpVEaDAr341tbn15RS4fCAsIst0qp7i8ex1o=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
@@ -57,6 +57,8 @@ github.com/rogpeppe/go-internal v1.11.0 h1:cWPaGQEPrBb5/AsnsZesgZZ9yb1OQ+GOISoDN
 github.com/rogpeppe/go-internal v1.11.0/go.mod h1:ddIwULY96R17DhadqLgMfk9H9tvdUzkipdSkR5nkCZA=
 github.com/shirou/gopsutil/v4 v4.24.12 h1:qvePBOk20e0IKA1QXrIIU+jmk+zEiYVVx06WjBRlZo4=
 github.com/shirou/gopsutil/v4 v4.24.12/go.mod h1:DCtMPAad2XceTeIAbGyVfycbYQNBGk2P8cvDi7/VN9o=
+github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
+github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/tklauser/go-sysconf v0.3.14 h1:g5vzr9iPFFz24v2KZXs/pvpvh8/V9Fw6vQK5ZZb78yU=
diff --git a/extension/opampextension/opamp_agent.go b/extension/opampextension/opamp_agent.go
index 3e26d407fd80..cca5f762ebe3 100644
--- a/extension/opampextension/opamp_agent.go
+++ b/extension/opampextension/opamp_agent.go
@@ -118,20 +118,20 @@ func (o *opampAgent) Start(ctx context.Context, host component.Host) error {
 		TLSConfig:      tls,
 		OpAMPServerURL: o.cfg.Server.GetEndpoint(),
 		InstanceUid:    types.InstanceUid(o.instanceID),
-		Callbacks: types.CallbacksStruct{
-			OnConnectFunc: func(_ context.Context) {
+		Callbacks: types.Callbacks{
+			OnConnect: func(_ context.Context) {
 				o.logger.Debug("Connected to the OpAMP server")
 			},
-			OnConnectFailedFunc: func(_ context.Context, err error) {
+			OnConnectFailed: func(_ context.Context, err error) {
 				o.logger.Error("Failed to connect to the OpAMP server", zap.Error(err))
 			},
-			OnErrorFunc: func(_ context.Context, err *protobufs.ServerErrorResponse) {
+			OnError: func(_ context.Context, err *protobufs.ServerErrorResponse) {
 				o.logger.Error("OpAMP server returned an error response", zap.String("message", err.ErrorMessage))
 			},
-			GetEffectiveConfigFunc: func(_ context.Context) (*protobufs.EffectiveConfig, error) {
+			GetEffectiveConfig: func(_ context.Context) (*protobufs.EffectiveConfig, error) {
 				return o.composeEffectiveConfig(), nil
 			},
-			OnMessageFunc: o.onMessage,
+			OnMessage: o.onMessage,
 		},
 		Capabilities: o.capabilities.toAgentCapabilities(),
 	}
diff --git a/receiver/awss3receiver/go.mod b/receiver/awss3receiver/go.mod
index fc101b5607cc..91d9e27f21df 100644
--- a/receiver/awss3receiver/go.mod
+++ b/receiver/awss3receiver/go.mod
@@ -7,7 +7,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/config v1.28.7
 	github.com/aws/aws-sdk-go-v2/feature/s3/manager v1.17.45
 	github.com/aws/aws-sdk-go-v2/service/s3 v1.72.0
-	github.com/open-telemetry/opamp-go v0.17.0
+	github.com/open-telemetry/opamp-go v0.18.0
 	github.com/open-telemetry/opentelemetry-collector-contrib/extension/opampcustommessages v0.117.0
 	github.com/stretchr/testify v1.10.0
 	go.opentelemetry.io/collector/component v0.117.0
diff --git a/receiver/awss3receiver/go.sum b/receiver/awss3receiver/go.sum
index f27b906fe21f..ff44222ee522 100644
--- a/receiver/awss3receiver/go.sum
+++ b/receiver/awss3receiver/go.sum
@@ -79,8 +79,8 @@ github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9Gz0M=
 github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
-github.com/open-telemetry/opamp-go v0.17.0 h1:3R4+B/6Sy8mknLBbzO3gqloqwTT02rCSRcr4ac2B124=
-github.com/open-telemetry/opamp-go v0.17.0/go.mod h1:SGDhUoAx7uGutO4ENNMQla/tiSujxgZmMPJXIOPGBdk=
+github.com/open-telemetry/opamp-go v0.18.0 h1:sNHsrBvGU2CMxCB1TRJXncDARrmxDEebx8dsEIawqA4=
+github.com/open-telemetry/opamp-go v0.18.0/go.mod h1:9/1G6T5dnJz4cJtoYSr6AX18kHdOxnxxETJPZSHyEUg=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=