diff --git a/.yoi/tickets/00001KVZ9JGK0/artifacts/relations.json b/.yoi/tickets/00001KVZ9JGK0/artifacts/relations.json
index 4a2a6038..4c9b04a0 100644
--- a/.yoi/tickets/00001KVZ9JGK0/artifacts/relations.json
+++ b/.yoi/tickets/00001KVZ9JGK0/artifacts/relations.json
@@ -1,6 +1,14 @@
 {
   "version": 1,
   "relations": [
+    {
+      "ticket_id": "00001KVZ9JGK0",
+      "kind": "depends_on",
+      "target": "00001KVZKSTJT",
+      "note": "Companion Web Console MVP has response stream / transcript projection choices and must not fix WS/SSE/polling behavior before `00001KVZKSTJT` resolves the WebSocket/event-stream transport design decision.",
+      "author": "yoi-orchestrator",
+      "at": "2026-06-25T20:22:58Z"
+    },
     {
       "ticket_id": "00001KVZ9JGK0",
       "kind": "depends_on",
diff --git a/.yoi/tickets/00001KVZ9JGK0/item.md b/.yoi/tickets/00001KVZ9JGK0/item.md
index e04d7157..52b57354 100644
--- a/.yoi/tickets/00001KVZ9JGK0/item.md
+++ b/.yoi/tickets/00001KVZ9JGK0/item.md
@@ -1,8 +1,8 @@
 ---
 title: 'Backend内蔵Companion RuntimeとWeb Console MVP'
-state: 'queued'
+state: 'planning'
 created_at: '2026-06-25T11:45:17Z'
-updated_at: '2026-06-25T16:45:24Z'
+updated_at: '2026-06-25T20:23:10Z'
 assignee: null
 queued_by: 'workspace-panel'
 queued_at: '2026-06-25T16:44:45Z'
diff --git a/.yoi/tickets/00001KVZ9JGK0/thread.md b/.yoi/tickets/00001KVZ9JGK0/thread.md
index aa345624..3426d04b 100644
--- a/.yoi/tickets/00001KVZ9JGK0/thread.md
+++ b/.yoi/tickets/00001KVZ9JGK0/thread.md
@@ -60,3 +60,28 @@ Escalate if:
 - Backend internal Runtime foundation の scope が Companion MVP requirements を満たさない。
 
 ---
+
+<!-- event: state_changed author: yoi-orchestrator at: 2026-06-25T20:23:10Z from: queued to: planning reason: web_console_stream_transport_decision_missing field: state -->
+
+## State changed
+
+ユーザー指摘により queued から planning に戻す。
+
+Missing decision / information:
+- 本 Ticket は Web Console MVP の conversation/transcript model で「request/response 完了後に transcript を返す」または「SSE / streaming endpoint」を実装時に選んでよいとしており、実質的に WS/SSE/polling/streaming の transport 方針を固定し得る。
+- これは `00001KVZKSTJT` で決定すべき WebSocket/event-stream transport 設計点であり、未決定のまま queued に置くのは不適切。
+
+Context checked:
+- Ticket body: Web Console UI、Companion message API、assistant response 取得または stream、conversation/transcript projection、Safety/authority。
+- Existing relation: `00001KVZSGT0Q` への dependency。
+- Added relation: `00001KVZKSTJT` への `depends_on` を追加し、WS/SSE/polling transport decision が解決するまで本 Ticket を blocker 付き planning として扱う。
+- `00001KVZKSTE2` は REST command server であり、SSE/WebSocket event stream server は Non-goal と明記されているため、この差し戻し対象ではない。
+
+Why implementation latitude is insufficient:
+- Web Console の response delivery を request/response、SSE、WebSocket、polling のどれに寄せるかは後続 API/UI/Backend runtime integration の binding decision であり、Coder の local tactic として固定すべきではない。
+
+Next planning question/action:
+- `00001KVZKSTJT` で WebSocket/event-stream transport の採否、Backend-owned client / Browser-facing projection / cursor semantics / busy/error behavior を決める。
+- その決定に基づいて、本 Ticket の conversation/transcript model と Web API acceptance criteria を再同期してから ready/queued に戻す。
+
+---