diff --git a/sessions/0001/SESSION-0001.0-TRANSCRIPT-2026-06-09T21-55--INPROGRESS.md b/sessions/0001/SESSION-0001.0-TRANSCRIPT-2026-06-09T21-55--INPROGRESS.md
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+# Session 0001.0 — Transcript
+
+> App: vs-code-cowriting-plugin
+> Start: 2026-06-09T21-55 (PST)
+> Type: capture
+> Status: **PLACEHOLDER — claimed at session start; finalized at session end.**
+>
+> This file reserves session ID 0001 for vs-code-cowriting-plugin. The driver replaces this
+> body with the full transcript and renames the file to its final
+> SESSION-0001.0-TRANSCRIPT-2026-06-09T21-55--<end>.md form at session end.
+
+## Launch prompt
+
+_(launch prompt not captured at claim time)_
+
+## Deferred decisions
+
+_Autonomous-mode low-confidence calls the driver made and would have
+liked operator input on. Appended as the session runs; surfaced at
+finalize. Empty if none._
diff --git a/sessions/sessions.json b/sessions/sessions.json
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+++ b/sessions/sessions.json
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+{
+  "0001": {
+    "title": ""
+  }
+}