diff --git a/internal/command/delta.go b/internal/command/delta.go
index 9d8a55e..2848a07 100644
--- a/internal/command/delta.go
+++ b/internal/command/delta.go
@@ -39,7 +39,7 @@ func init() {
 	deltaCmd.MarkFlagRequired("env")
 
 	deltaCmd.Flags().StringArrayVarP(&overrideParams, "property", "p", nil, "Overrides selected property value")
-	deltaCmd.Flags().StringVar(&message, "message", "m", messageDefault, "Message")
+	deltaCmd.Flags().StringVarP(&message, "message", "m", messageDefault, "Message")
 
 	deltaCmd.Flags().BoolVar(&deploy, "deploy", false, "Trigger a new delta deployment at the end")
 	deltaCmd.Flags().BoolVar(&retry, "retry", false, "Retry deployments when a deployment is currently in progress")
diff --git a/internal/command/run.go b/internal/command/run.go
index 798e657..c8dc2c9 100644
--- a/internal/command/run.go
+++ b/internal/command/run.go
@@ -39,7 +39,7 @@ func init() {
 	runCmd.MarkFlagRequired("env")
 
 	runCmd.Flags().StringArrayVarP(&overrideParams, "property", "p", nil, "Overrides selected property value")
-	runCmd.Flags().StringVar(&message, "message", "m", messageDefault, "Message")
+	runCmd.Flags().StringVarP(&message, "message", "m", messageDefault, "Message")
 
 	runCmd.Flags().BoolVar(&skipValidation, "skip-validation", false, "DEPRECATED: Disables Score file schema validation.")
 	runCmd.Flags().BoolVar(&verbose, "verbose", false, "Enable diagnostic messages (written to STDERR)")
diff --git a/internal/humanitec_go/client/client.go b/internal/humanitec_go/client/client.go
index 3feaf47..05cb3a0 100644
--- a/internal/humanitec_go/client/client.go
+++ b/internal/humanitec_go/client/client.go
@@ -8,14 +8,21 @@ The Apache Software Foundation (http://www.apache.org/).
 package client
 
 import (
+	"fmt"
 	"net/http"
 
+	"github.com/score-spec/score-humanitec/internal/version"
 	"github.com/sendgrid/rest"
 )
 
+var (
+	ScoreUserAgent = fmt.Sprintf("score-humanitec/%s", version.Version)
+)
+
 type apiClient struct {
-	baseUrl string
-	token   string
+	baseUrl            string
+	token              string
+	humanitecUserAgent string
 
 	client *rest.Client
 }
@@ -23,8 +30,9 @@ type apiClient struct {
 // NewClient constructs new Humanitec API client.
 func NewClient(url, token string, httpClient *http.Client) (Client, error) {
 	return &apiClient{
-		baseUrl: url,
-		token:   token,
+		baseUrl:            url,
+		token:              token,
+		humanitecUserAgent: fmt.Sprintf("app %s; sdk %s", ScoreUserAgent, ScoreUserAgent),
 
 		client: &rest.Client{
 			HTTPClient: httpClient,
diff --git a/internal/humanitec_go/client/deltas.go b/internal/humanitec_go/client/deltas.go
index 9ba7a55..29703b5 100644
--- a/internal/humanitec_go/client/deltas.go
+++ b/internal/humanitec_go/client/deltas.go
@@ -32,9 +32,10 @@ func (api *apiClient) CreateDelta(ctx context.Context, orgID, appID string, delt
 		Method:  http.MethodPost,
 		BaseURL: api.baseUrl + apiPath,
 		Headers: map[string]string{
-			"Authorization": "Bearer " + api.token,
-			"Content-Type":  "application/json",
-			"Accept":        "application/json",
+			"Authorization":        "Bearer " + api.token,
+			"Content-Type":         "application/json",
+			"Accept":               "application/json",
+			"Humanitec-User-Agent": api.humanitecUserAgent,
 		},
 		Body: data,
 	}
@@ -76,9 +77,10 @@ func (api *apiClient) UpdateDelta(ctx context.Context, orgID string, appID strin
 		Method:  http.MethodPatch,
 		BaseURL: api.baseUrl + apiPath,
 		Headers: map[string]string{
-			"Authorization": "Bearer " + api.token,
-			"Content-Type":  "application/json",
-			"Accept":        "application/json",
+			"Authorization":        "Bearer " + api.token,
+			"Content-Type":         "application/json",
+			"Accept":               "application/json",
+			"Humanitec-User-Agent": api.humanitecUserAgent,
 		},
 		Body: buf.Bytes(),
 	}
diff --git a/internal/humanitec_go/client/deltas_test.go b/internal/humanitec_go/client/deltas_test.go
index 4016bd7..1df7870 100644
--- a/internal/humanitec_go/client/deltas_test.go
+++ b/internal/humanitec_go/client/deltas_test.go
@@ -57,7 +57,7 @@ func TestCreateDelta(t *testing.T) {
 			Response: []byte(`{
 				"id": "qwe...rty",
 				"metadata": { "env_id": "test", "name": "Test delta" },
-				"modules": { 
+				"modules": {
 					"add": { "module-01": { "image": "busybox", "variables": { "TEST": "<a>" } } }
 				}
 			}`),
@@ -111,6 +111,7 @@ func TestCreateDelta(t *testing.T) {
 							assert.Equal(t, []string{"Bearer " + apiToken}, r.Header["Authorization"])
 							assert.Equal(t, []string{"application/json"}, r.Header["Accept"])
 							assert.Equal(t, []string{"application/json"}, r.Header["Content-Type"])
+							assert.Equal(t, []string{"app score-humanitec/0.0.0; sdk score-humanitec/0.0.0"}, r.Header["Humanitec-User-Agent"])
 
 							if tt.Data != nil {
 								var body humanitec.CreateDeploymentDeltaRequest
@@ -168,6 +169,7 @@ func TestUpdateDelta_success(t *testing.T) {
 					assert.Equal(t, []string{"Bearer " + apiToken}, r.Header["Authorization"])
 					assert.Equal(t, []string{"application/json"}, r.Header["Accept"])
 					assert.Equal(t, []string{"application/json"}, r.Header["Content-Type"])
+					assert.Equal(t, []string{"app score-humanitec/0.0.0; sdk score-humanitec/0.0.0"}, r.Header["Humanitec-User-Agent"])
 					var body []*humanitec.UpdateDeploymentDeltaRequest
 					var dec = json.NewDecoder(r.Body)
 					assert.NoError(t, dec.Decode(&body))
diff --git a/internal/humanitec_go/client/deployments.go b/internal/humanitec_go/client/deployments.go
index b30a475..812afb5 100644
--- a/internal/humanitec_go/client/deployments.go
+++ b/internal/humanitec_go/client/deployments.go
@@ -35,9 +35,10 @@ func (api *apiClient) StartDeployment(ctx context.Context, orgID, appID, envID s
 		Method:  http.MethodPost,
 		BaseURL: api.baseUrl + apiPath,
 		Headers: map[string]string{
-			"Authorization": "Bearer " + api.token,
-			"Content-Type":  "application/json",
-			"Accept":        "application/json",
+			"Authorization":        "Bearer " + api.token,
+			"Content-Type":         "application/json",
+			"Accept":               "application/json",
+			"Humanitec-User-Agent": api.humanitecUserAgent,
 		},
 		Body: data,
 	}
diff --git a/internal/humanitec_go/client/deployments_test.go b/internal/humanitec_go/client/deployments_test.go
index 3f338f2..c4970eb 100644
--- a/internal/humanitec_go/client/deployments_test.go
+++ b/internal/humanitec_go/client/deployments_test.go
@@ -149,6 +149,7 @@ func TestStartDeployment(t *testing.T) {
 							assert.Equal(t, []string{"Bearer " + apiToken}, r.Header["Authorization"])
 							assert.Equal(t, []string{"application/json"}, r.Header["Accept"])
 							assert.Equal(t, []string{"application/json"}, r.Header["Content-Type"])
+							assert.Equal(t, []string{"app score-humanitec/0.0.0; sdk score-humanitec/0.0.0"}, r.Header["Humanitec-User-Agent"])
 
 							if tt.Data != nil {
 								var body humanitec.StartDeploymentRequest
diff --git a/internal/humanitec_go/client/resources.go b/internal/humanitec_go/client/resources.go
index bcb3b05..6a052e7 100644
--- a/internal/humanitec_go/client/resources.go
+++ b/internal/humanitec_go/client/resources.go
@@ -25,8 +25,9 @@ func (api *apiClient) ListResourceTypes(ctx context.Context, orgID string) ([]hu
 		Method:  http.MethodGet,
 		BaseURL: api.baseUrl + apiPath,
 		Headers: map[string]string{
-			"Authorization": "Bearer " + api.token,
-			"Accept":        "application/json",
+			"Authorization":        "Bearer " + api.token,
+			"Accept":               "application/json",
+			"Humanitec-User-Agent": api.humanitecUserAgent,
 		},
 	}
 
diff --git a/internal/humanitec_go/client/resources_test.go b/internal/humanitec_go/client/resources_test.go
index 3b953bc..aaf1e20 100644
--- a/internal/humanitec_go/client/resources_test.go
+++ b/internal/humanitec_go/client/resources_test.go
@@ -111,6 +111,7 @@ func TestListResourceTypes(t *testing.T) {
 							}
 							assert.Equal(t, []string{"Bearer " + apiToken}, r.Header["Authorization"])
 							assert.Equal(t, []string{"application/json"}, r.Header["Accept"])
+							assert.Equal(t, []string{"app score-humanitec/0.0.0; sdk score-humanitec/0.0.0"}, r.Header["Humanitec-User-Agent"])
 
 							w.WriteHeader(tt.StatusCode)
 							if len(tt.Response) > 0 {