diff --git a/internal/cli/lock.go b/internal/cli/lock.go
index 6fa7e9b9e0..18769af01d 100644
--- a/internal/cli/lock.go
+++ b/internal/cli/lock.go
@@ -1137,9 +1137,11 @@ func isTreeLockField(field string) bool {
 // use forge tree URLs whose deepest path segment is the directory name.
 // Base-composed entries (see fetchBaseSkill/fetchBasePlugin in
 // internal/harness/compose.go) record raw.githubusercontent.com URLs pointing
-// at the marker file (SKILL.md or plugin.json); only those two names are
-// treated as markers and stripped — any other raw URL keeps its last segment
-// as the directory name.
+// at the marker file (SKILL.md, plugin.json, or .claude-plugin/plugin.json);
+// those names are treated as markers and stripped — any other raw URL keeps
+// its last segment as the directory name. .claude-plugin/plugin.json is the
+// Claude Code plugin spec location; stripping it requires removing two path
+// segments so the caller gets the plugin root, not ".claude-plugin".
 func lockTreeDirName(field, lockURL string) (string, error) {
 	if forgeInfo, err := forge.ParseForgeURL(lockURL); err == nil {
 		if forgeInfo.Path == "" {
@@ -1153,6 +1155,15 @@ func lockTreeDirName(field, lockURL string) (string, error) {
 			if dir == "." {
 				return "", fmt.Errorf("%s: URL must point to a marker file inside a directory, not the repo root", field)
 			}
+			// .claude-plugin/plugin.json is a two-level marker per the
+			// Claude Code plugin spec; strip the intermediate directory
+			// so the caller gets the plugin root, not ".claude-plugin".
+			if last == "plugin.json" && path.Base(dir) == ".claude-plugin" {
+				dir = path.Dir(dir)
+				if dir == "." {
+					return "", fmt.Errorf("%s: URL must point to a marker file inside a directory, not the repo root", field)
+				}
+			}
 			return filepath.Base(dir), nil
 		}
 		return path.Base(rawInfo.Path), nil
diff --git a/internal/cli/lock_test.go b/internal/cli/lock_test.go
index b9224f03a5..c683e6f76e 100644
--- a/internal/cli/lock_test.go
+++ b/internal/cli/lock_test.go
@@ -2437,6 +2437,18 @@ func TestLockTreeDirName(t *testing.T) {
 			url:   "https://raw.githubusercontent.com/org/repo/abc123/plugins/gopls-lsp/plugin.json",
 			want:  "gopls-lsp",
 		},
+		{
+			name:  "raw .claude-plugin/plugin.json marker stripped",
+			field: "plugins[0]",
+			url:   "https://raw.githubusercontent.com/org/repo/abc123/plugins/my-plugin/.claude-plugin/plugin.json",
+			want:  "my-plugin",
+		},
+		{
+			name:    "raw .claude-plugin/plugin.json at ref root rejected",
+			field:   "plugins[0]",
+			url:     "https://raw.githubusercontent.com/org/repo/abc123/.claude-plugin/plugin.json",
+			wantErr: "must point to a marker file inside a directory",
+		},
 		{
 			name:    "raw marker at ref root rejected",
 			field:   "skills[0]",