diff --git a/internal/identity/footer.go b/internal/identity/footer.go
new file mode 100644
index 0000000..a57dc9e
--- /dev/null
+++ b/internal/identity/footer.go
@@ -0,0 +1,14 @@
+package identity
+
+import "strings"
+
+func ApplyFooter(body, caller string) string {
+	if caller == "" {
+		return body
+	}
+	footer := "\n\n---\n_Created via git-mcp on behalf of @" + caller + "_"
+	if strings.HasSuffix(body, footer) {
+		return body
+	}
+	return body + footer
+}
diff --git a/internal/identity/footer_test.go b/internal/identity/footer_test.go
new file mode 100644
index 0000000..e30aa8e
--- /dev/null
+++ b/internal/identity/footer_test.go
@@ -0,0 +1,19 @@
+package identity_test
+
+import (
+	"testing"
+
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/identity"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestApplyFooterAppendsWhenCallerSet(t *testing.T) {
+	body := identity.ApplyFooter("Initial body.", "mathiasbq")
+	assert.Contains(t, body, "Initial body.")
+	assert.Contains(t, body, "_Created via git-mcp on behalf of @mathiasbq_")
+}
+
+func TestApplyFooterUnchangedWhenCallerEmpty(t *testing.T) {
+	body := identity.ApplyFooter("Initial body.", "")
+	assert.Equal(t, "Initial body.", body)
+}