diff --git a/dev-claude-plugin/0004/SESSION-0004.0-TRANSCRIPT-2026-06-03T18-26--INPROGRESS.md b/dev-claude-plugin/0004/SESSION-0004.0-TRANSCRIPT-2026-06-03T18-26--INPROGRESS.md
new file mode 100644
index 0000000..79e72c1
--- /dev/null
+++ b/dev-claude-plugin/0004/SESSION-0004.0-TRANSCRIPT-2026-06-03T18-26--INPROGRESS.md
@@ -0,0 +1,13 @@
+# Session 0004.0 — Transcript
+
+> App: dev-claude-plugin
+> Start: 2026-06-03T18-26 (PST)
+> Status: **PLACEHOLDER — claimed at session start; finalized at session end.**
+>
+> This file reserves session ID 0004 for dev-claude-plugin. The driver replaces this
+> body with the full transcript and renames the file to its final
+> SESSION-0004.0-TRANSCRIPT-2026-06-03T18-26--<end>.md form at session end.
+
+## Launch prompt
+
+_(launch prompt not captured at claim time)_
diff --git a/dev-claude-plugin/sessions.json b/dev-claude-plugin/sessions.json
index 9c427e6..39092c0 100644
--- a/dev-claude-plugin/sessions.json
+++ b/dev-claude-plugin/sessions.json
@@ -7,5 +7,8 @@
   },
   "0003": {
     "title": ""
+  },
+  "0004": {
+    "title": ""
   }
 }