diff --git a/managed/services/inventory/agents.go b/managed/services/inventory/agents.go
index 5ec7396713b..1da2af41943 100644
--- a/managed/services/inventory/agents.go
+++ b/managed/services/inventory/agents.go
@@ -20,7 +20,6 @@ import (
 	"context"
 
 	"github.com/AlekSi/pointer"
-	"github.com/pkg/errors"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 	"gopkg.in/reform.v1"
@@ -502,7 +501,7 @@ func (as *AgentsService) ChangeQANMySQLSlowlogAgent(ctx context.Context, req *in
 // AddPostgresExporter inserts postgres_exporter Agent with given parameters.
 func (as *AgentsService) AddPostgresExporter(ctx context.Context, req *inventorypb.AddPostgresExporterRequest) (*inventorypb.PostgresExporter, error) {
 	if req.AutoDiscoveryLimit < 0 {
-		return nil, errors.New("auto discovery limit cannot be lower than 0")
+		return nil, status.Errorf(codes.InvalidArgument, "auto_discovery_limit cannot be lower than 0")
 	}
 
 	var res *inventorypb.PostgresExporter
diff --git a/managed/services/management/postgresql.go b/managed/services/management/postgresql.go
index 245346eaffb..96208b4fe1a 100644
--- a/managed/services/management/postgresql.go
+++ b/managed/services/management/postgresql.go
@@ -19,7 +19,8 @@ import (
 	"context"
 
 	"github.com/AlekSi/pointer"
-	"github.com/pkg/errors"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 	"gopkg.in/reform.v1"
 
 	"github.com/percona/pmm/api/inventorypb"
@@ -49,7 +50,7 @@ func NewPostgreSQLService(db *reform.DB, state agentsStateUpdater, cc connection
 // Add adds "PostgreSQL Service", "PostgreSQL Exporter Agent" and "QAN PostgreSQL PerfSchema Agent".
 func (s *PostgreSQLService) Add(ctx context.Context, req *managementpb.AddPostgreSQLRequest) (*managementpb.AddPostgreSQLResponse, error) {
 	if req.AutoDiscoveryLimit < 0 {
-		return nil, errors.New("auto discovery limit cannot be lower than 0")
+		return nil, status.Errorf(codes.InvalidArgument, "auto_discovery_limit cannot be lower than 0")
 	}
 
 	res := &managementpb.AddPostgreSQLResponse{}