commit - 00a66b61a581bd514c70d7170958032fb0129bf7
commit + 1738cb32b92b94d71cf623fa3e84afaef401a211
blob - 0ba7ff4eb378b0ba7e6afead99b05991a4dd552b
blob + b51d6126a1a803d43253f2f12cb04b127470f2f9
--- apub.go
+++ apub.go
@@ -54,6 +54,7 @@ type Activity struct {
 	} `json:"source,omitempty"`
 	PublicKey *PublicKey      `json:"publicKey,omitempty"`
 	Audience  string          `json:"audience,omitempty"`
+	Tag       []Activity      `json:"tag,omitempty"`
 	Object    json.RawMessage `json:"object,omitempty"`
 }
 
blob - c262154f5b118c860be68a4b293b7685d9d63e73
blob + 4117b5de1e745b4944071681904bb67c6bdb4738
--- apub_test.go
+++ apub_test.go
@@ -24,3 +24,40 @@ func TestDecode(t *testing.T) {
 		t.Errorf("wanted wrapped activity id %s, got %s", want, inner.ID)
 	}
 }
+
+func TestTag(t *testing.T) {
+	tests := []struct {
+		Name    string
+		Mention string
+	}{
+		{"testdata/note/akkoma.json", "@otl@apubtest2.srcbeat.com"},
+		{"testdata/note/lemmy.json", "@Feathercrown@lemmy.world"},
+		{"testdata/note/mastodon.json", "@selfhosted@lemmy.world"},
+	}
+	for _, tt := range tests {
+		f, err := os.Open(tt.Name)
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+		defer f.Close()
+		a, err := Decode(f)
+		if err != nil {
+			t.Errorf("%s: decode: %v", tt.Name, err)
+			continue
+		}
+		if len(a.Tag) == 0 {
+			t.Errorf("%s: no tags", tt.Name)
+			continue
+		}
+		var found bool
+		for _, tag := range a.Tag {
+			if tag.Name == tt.Mention {
+				found = true
+			}
+		}
+		if !found {
+			t.Errorf("%s: did not find mention %s", tt.Name, tt.Mention)
+		}
+	}
+}