docs: refresh HANDOVER for floating panel work (d412130)

Captures the state after the per-cell -> global floating panel refactor
plus the hide+show accumulation fix. Includes:
- New commit history and validation status (jest 68, pytest 73, tsc OK)
- Full file-change table for the 6 files touched this session
- OpenCodeFloatingPanel design notes (lifecycle, state, API)
- Detailed writeup of the d412130 bug + defensive DOM cleanup fix
  + the test's known limitation (mock is more lenient than real Lumino)
- Outstanding work for next session: real JupyterLab test, Playwright,
  jlpm build:prod, pre-existing lint cleanup
- Critical context: kimi/kimi-k2.7-code was rejected by Codex proxy
  throughout this session; CC fallback was used for almost all code work

HANDOVER.md

@@ -0,0 +1,207 @@
+# opencode_bridge 交接文档
+
+## 状态速览
+
+**分支**:`feature/floating-ai-button`(已 push,tracking 已设)
+**远端**:`http://101.43.40.124:3000/tao.chen/notebook-ai-extension.git`
+**基础**:`main` @ `310d507`(上次 HANDOVER 时的版本)
+**当前 HEAD**:`d412130`
+**提交**:
+```
+d412130 fix: hide+show cycles no longer accumulate prompt nodes in floating panel
+c0eba7e feat: replace per-cell AI button with global floating panel
+f9d52f7 docs: add HANDOVER.md for next session context
+310d507 fix: SSE filter no longer drops content events for a different session
+```
+
+**验证**:✅ Jest 68/68 · ✅ pytest 73/73 · ✅ tsc exit 0 · ⚠️ 2 个 pre-existing lint 错(`FlatProvider`/`BlockEntry` 命名约定,在 `inline_prompt.ts` 里,我没引入)
+
+**PR**:未提。Gitea 链接:
+```
+http://101.43.40.124:3000/tao.chen/notebook-ai-extension/pulls/new/feature/floating-ai-button
+```
+
+---
+
+## 本次会话做了什么
+
+**架构变更**:把 per-cell 工具栏 AI 按钮(原 `OpenCodeCellActions`)整个换成全局右下角悬浮按钮 + 弹出 panel。**不是并存**,是完全替换 — per-cell 路径已删除。
+
+```
+Before                              After
+─────────────────────────────────    ─────────────────────────────────
+Cell 工具栏 → per-cell 按钮          document.body 右下角固定按钮(🪄)
+            ↓ click                            ↓ click
+       内嵌 prompt panel(挂到 cell)         悬浮 prompt panel(挂在按钮上方)
+            ↓                                      ↓
+       当前 cell 是 owner                      从 app.shell.currentWidget 取 active notebook
+            ↓                                      ↓
+       "📋 插入单元格内容" 用 this._cell       通过 getActiveCell() 回调拿 active cell
+```
+
+---
+
+## 关键改动文件
+
+| 文件 | 改动 |
+|------|------|
+| `src/components/opencode_floating_panel.ts` | **新增** — 全局按钮 + panel 容器(详见下文) |
+| `src/components/opencode_cell_actions.ts` | **删除** — 逻辑全部搬到 floating panel |
+| `src/components/opencode_inline_prompt.ts` | 解耦 CodeCell。新增 `getActiveCell?: () => CodeCell \| null` 选项。3 处方法(`_insertCellSource` / `_insertAtCursor` / `_replaceCell`)改用回调。`setDisabled()` 在构造器末尾调一次,确保 insert button 初始 disabled 状态正确 |
+| `src/index.ts` | 删 `toolbarRegistry.addFactory` + `IToolbarWidgetRegistry` optional。新建 `OpenCodeFloatingPanel` 挂到 `document.body` |
+| `style/base.css` | 删 `.opencode-cell-actions` 块。新增 `.opencode-floating-root` / `.opencode-floating-button` / `.opencode-floating-panel` 样式(fixed 定位、z-index 1000、480px 宽、60vh 高) |
+| `src/__tests__/opencode_floating_panel.spec.ts` | 重命名 + 重写。原 1663 行 → 现在 1556 行。67 → 68 tests |
+
+---
+
+## OpenCodeFloatingPanel 设计要点
+
+### DOM 结构
+```
+<div class="opencode-floating-root">       (position: fixed; bottom: 24; right: 24)
+  <button class="opencode-floating-button">🪄</button>
+  <div class="opencode-floating-panel" hidden>
+    <!-- OpenCodeInlinePrompt 在这里 -->
+  </div>
+</div>
+```
+
+### 生命周期
+- 构造:创建 button + panel 容器,挂到 `document.body`,监听 `app.shell.currentChanged`
+- toggle():if hidden → _showPrompt;else → _hidePrompt
+- `_showPrompt()`:resolve 当前 notebook path + active cell lambda → 构造 `OpenCodeInlinePrompt` → 用 **`Widget.attach(prompt, this._panelEl)`** 挂上 → 调 `prompt.initialize()` 拉 session list → 显示
+- `_hidePrompt()`:close SSE → dispose prompt → **defensive DOM cleanup**(见下)→ 设 `this._prompt = null` → 隐藏 panel
+
+### State 全在 panel 上(原来在 cell action 上的都搬过来了)
+- `_app: JupyterFrontEnd`
+- `_serverSettings: ServerConnection.ISettings | null`(构造器传入)
+- `_providers: OpenCodeProvidersResponse | null`(构造器传入,通过 `setProviders()` 方法更新)
+- `_prompt: OpenCodeInlinePrompt | null`
+- `_sseSub: OpenCodeEventSubscription | null`
+- `_notebookPath: string | null`
+- `_status: 'idle' | 'loading'`
+
+### API(对外)
+```ts
+class OpenCodeFloatingPanel extends Widget {
+  constructor(options: {
+    app: JupyterFrontEnd;
+    serverSettings: ServerConnection.ISettings;
+    providers: OpenCodeProvidersResponse | null;
+  });
+  setProviders(p: OpenCodeProvidersResponse | null): void;  // index.ts 在 providers fetch 完后调
+  toggle(): void;
+}
+```
+
+---
+
+## ⚠️ 刚修的 bug(d412130)
+
+**症状**:点击悬浮按钮 → 显示 panel。点第二次 → 隐藏。点第三次 → **看到 2 个 prompt 同时显示**(节点累积)。
+
+**根因**:`OpenCodeInlinePrompt` 是 Lumino Widget,但我们用 `Widget.attach(prompt, this._panelEl)` 把 prompt 挂到一个裸的 `HTMLDivElement` 上(host 不是 Widget)。Lumino 的 `Widget.dispose()` 检查 `this.parent` 然后 `this.isAttached`:
+- `this.parent === null`(HTMLElement host 不会建立 Lumino parent)
+- `this.isAttached === true`(节点确实在 DOM 里)
+- 走 `Widget.detach(this)` 分支 — **理论上能清理**
+
+但在某些场景下(可能是 message loop 时序 / widget tree 重排),dispose 不会移除 DOM 节点,残留累积。
+
+**修法**(`_hidePrompt` 里加 defensive cleanup):
+```ts
+if (this._prompt) {
+  const node = this._prompt.node;
+  this._prompt.dispose();
+  // Defensive: ensure DOM cleanup even if dispose() missed it
+  if (node.parentNode === this._panelEl) {
+    this._panelEl.removeChild(node);
+  }
+  this._prompt = null;
+}
+```
+
+**Regression test**(`opencode_floating_panel.spec.ts`):
+```ts
+it('hide+show cycles do not accumulate prompt nodes in the panel (regression)', () => {
+  for (let i = 0; i < 5; i++) { panel.toggle(); panel.toggle(); }
+  panel.toggle();
+  expect(panelEl.querySelectorAll('.opencode-inline-prompt').length).toBe(1);
+});
+```
+
+⚠️ **测试局限**:测试 mock 的 `Widget.dispose()` 直接用 `node.parentNode.removeChild`,比真实 Lumino 更激进清理。**这个 regression test 在 mock 下永远会过**,对真实 bug 的保护力有限 — 真实 Lumino 才是 bug 触发环境。如果你怀疑类似 bug 复发,**必须在真实 JupyterLab 里手测**,不要只看 jest pass。
+
+---
+
+## 关键设计决策(避免来回改)
+
+1. **不用并存模式** — per-cell 按钮完全删除。Linus "good taste" 原则,消除 special case。
+2. **Active cell 通过 shell 拿** — `app.shell.currentWidget.content.activeCell`,不是 per-cell 硬绑定。Cell 是 `CodeCell | null`,null 时 `getActiveCell()` 返回 null,prompt 用 `Notification.info('请先选中一个 cell')` 提示。
+3. **`_onShellChanged` 是箭头函数 class field**(`= (): void => { ... }`)— Lumino signal 调用时 `this` 不一定正确绑定,arrow function 把 `this` 锁死在实例上。
+4. **Defensive DOM cleanup** — 见上面 bug 段。任何把 Lumino widget 挂到非 Widget host 上的代码都应该有这层保险。
+5. **Mock 的 `Widget.dispose()` 比真实 Lumino 更"宽容"** — 见 bug 段的测试局限说明。
+
+---
+
+## 仍未做的事(如果继续)
+
+- [ ] **真实 JupyterLab + OpenCode Serve 端到端测试** — 我只做了 build/jest/pytest,没在活的 JupyterLab 里点过。bug d412130 是用户手测报的。
+- [ ] **Playwright UI tests** — 项目交接文档里说过写过 spec 但没跑,我没动这块。
+- [ ] **`jlpm build:prod`** — 尝试运行但 venv 里 jlpm 入口有问题(`.venv/bin/jlpm` 是 Python 脚本,`main()` 调用对不上),用户没让我再继续 debug 这块。我跑了 `jest` + `tsc --noEmit` 间接验证了编译能过,但完整 labextension 打包没跑过。
+- [ ] **pre-existing lint 错的处理** — `FlatProvider` / `BlockEntry` 接口名不符合项目 `/^I[A-Z]/u` 规则。这两个是我接手前就存在的。可以单独提一个 cleanup commit。
+- [ ] **`tsconfig.json` 没动** — strict mode 让我新加了几处 `as any`(`this._app.shell as any`),是因为 JupyterLab 类型里 `JupyterFrontEnd.shell` 在某些版本是 `JupyterShell | null`。可以后续更精确处理。
+
+---
+
+## 环境 / 工具注意事项(下一个 agent 必读)
+
+### Codex 走得很坎坷 ⚠️⚠️⚠️
+
+CLAUDE.md 强制要求 Codex `model: kimi/kimi-k2.7-code`,但本会话中这个模型在火山方舟 Coding Plan 上**反复返回 HTTP 400**:
+
+| 错误 | 频率 |
+|------|------|
+| `model: kimi-k2.7-code is not valid`(早期,模型名错) | 2 次 |
+| `reasoning is not supported by current model`(用户修了 proxy 后) | 多次 |
+| 一次 noop 通了,然后实际任务失败 | 1 次 |
+
+CLAUDE.md 现在的版本是 `kimi/kimi-k2.7-code`(带 `kimi/` 前缀),但**仍然被 proxy 拒绝**。**建议**:
+1. 下次会话先 `noop` 测一下,通了再发真任务
+2. 不通就走 CC fallback(按 CLAUDE.md fallback 规则:`codex-fail-3x → switch-to-cc`)
+3. 真要走 Codex,可能需要 proxy 侧明确配置(我无法触及)
+
+我大部分代码工作都是 CC 手动做的。Codex 临死前**做了一件有用的事**:它已经重写了 spec 文件的 65%(包括 rename + mock 更新 + `getActiveCell` 适配 + `makeFakeApp` helper),省了我不少力气。
+
+### jlpm 在 venv 里不能直接用
+
+`.venv/bin/jlpm` 是 Python 脚本入口(`from jupyter_builder.jlpm import main`)。用户终端环境可能直接有 `jlpm`,但我的环境没有。`python -m jupyter_builder.jlpm` 也没成功。
+
+如果下一个 agent 需要跑 `jlpm build:prod` 或 `jlpm watch`,建议先确认 `which jlpm` 能找到。
+
+### 分支保护
+
+`feature/floating-ai-button` 没合并到 `main`,还在 review 阶段。`main` 仍是 `310d507`。如果新会话要在 `main` 上继续,先确认这个分支的 PR 是否已合。
+
+---
+
+## 测试命令(确认改动没破坏)
+
+```bash
+.venv/bin/pytest opencode_bridge/tests/ -q                    # 73 passed
+./node_modules/.bin/jest --no-coverage                       # 68 passed (3 suites)
+./node_modules/.bin/tsc --noEmit                             # exit 0
+./node_modules/.bin/eslint --ext .ts,.tsx src/                # 仅 pre-existing 错
+```
+
+---
+
+## 上下文管理提示
+
+我已经快把 context 烧完了(写这个交接文档前已经是大半)。如果新会话第一件事是"继续上次工作":
+
+1. 读这份 HANDOVER.md 全文
+2. 看 `git log feature/floating-ai-button` 确认 commit hash 没变(`d412130`)
+3. 跑上面 4 个验证命令,确认环境干净
+4. 然后读这次提交改动的 6 个文件,优先 `src/components/opencode_floating_panel.ts` 和 `src/__tests__/opencode_floating_panel.spec.ts`
+
+**不要**:`git checkout main` 然后从 main 重新开始 — 这会丢失当前未合并的分支历史。直接在 `feature/floating-ai-button` 上继续即可。

opencode_bridge/opencode_client.py

@@ -159,6 +159,16 @@ class OpenCodeClient:
         """
         return await self._request("GET", "/session/%s/message" % session_id)
 
+    async def list_all_sessions(self) -> list[dict[str, Any]]:
+        """List ALL sessions on the OpenCode Serve side (not just the ones
+        bound to a notebook in our SessionManager).
+
+        Returns the raw OpenCode response: a list of session objects with
+        metadata (``id``, ``title``, ``createdAt``, ``updatedAt``,
+        ``messageCount`` etc., whatever the upstream returns).
+        """
+        return await self._request("GET", "/session")
+
     @property
     def endpoint(self) -> str:
         return self._config.url

opencode_bridge/routes.py

@@ -48,44 +48,19 @@ def get_session_manager(handler: APIHandler) -> SessionManager:
     return sm
 
 
-def _build_request_body(prompt: str, context: dict) -> dict:
+def _build_request_body(prompt: str) -> dict:
-    """Build full request body for OpenCode POST /session/:id/prompt_async.
+    """Build request body for OpenCode POST /session/:id/prompt_async.
 
-    Returns dict with 'parts' (list) and 'system' (str) keys. No mode concept:
+    v0.2.x: only the user's prompt is sent to the LLM. We no longer
-    the LLM interprets the user's natural-language instruction, with the code
+    auto-wrap the cell source / previous-cell / traceback in tags —
-    context and the optional traceback in front of it.
+    the user inserts whatever they want via the "📋 插入单元格内容"
+    button (or pastes manually), so the LLM context exactly matches
+    user intent. Returns dict with 'parts' and 'system' keys.
     """
-    parts: list[dict] = []
+    return {
-
+        "parts": [{"type": "text", "text": prompt}],
-    if context.get("previousCode"):
+        "system": UNIFIED_SYSTEM_PROMPT,
-        parts.append({
+    }
-            "type": "text",
-            "text": "<previous_cell>\n%s\n</previous_cell>\n" % context["previousCode"],
-        })
-
-    error = context.get("error")
-    if error:
-        parts.append({
-            "type": "text",
-            "text": (
-                "<traceback>\n%s: %s\n" % (error["ename"], error["evalue"])
-                + "\n".join(error.get("traceback", []))
-                + "\n</traceback>\n"
-            ),
-        })
-
-    parts.append({
-        "type": "text",
-        "text": "<cell language='%s'>\n%s\n</cell>\n" % (
-            context.get("language", "python"),
-            context["source"],
-        ),
-    })
-
-    if prompt:
-        parts.append({"type": "text", "text": "<instruction>\n%s\n</instruction>" % prompt})
-
-    return {"parts": parts, "system": UNIFIED_SYSTEM_PROMPT}
 
 
 def _strip_code_fence(s: str) -> str:
@@ -204,7 +179,7 @@ class EditHandler(APIHandler):
         sm = get_session_manager(self)
         try:
             sid = await sm.get_or_create(notebook_path)
-            request_body = _build_request_body(prompt, context)
+            request_body = _build_request_body(prompt)
             await client.send_message_async(
                 sid,
                 request_body["parts"],
@@ -458,6 +433,242 @@ class SessionMessagesHandler(APIHandler):
         self.finish(json.dumps({"messages": messages}))
 
 
+# ---------------------------------------------------------------------------
+# Multi-session management endpoints
+# ---------------------------------------------------------------------------
+#
+# Model: each notebook can have multiple OpenCode sessions bound to it.
+# One of the bound sessions is the "active" one (used by the next /edit).
+# The user can:
+#   - list all OpenCode sessions (global, for the "browse" UI)
+#   - list sessions bound to a specific notebook
+#   - create a brand-new session and bind it (becomes active)
+#   - bind an existing session id (e.g. one they saw in the global list)
+#   - switch which bound session is active
+#   - unbind the active one (next /edit will lazy-create a new one)
+#   - delete a specific bound session (also removes it from OpenCode Serve)
+# ---------------------------------------------------------------------------
+
+
+class AllSessionsListHandler(APIHandler):
+    """GET /opencode-bridge/sessions/all — list EVERY session on OpenCode
+    Serve, regardless of which notebook (if any) it is bound to. Powers
+    the "browse all conversations" UI in the cell-action panel.
+    """
+
+    @tornado.web.authenticated
+    async def get(self):
+        try:
+            client = make_client(self)
+            sessions = await client.list_all_sessions()
+        except OpenCodeError as e:
+            log.exception("list all sessions failed")
+            self.set_status(502)
+            self.finish(json.dumps({"ok": False, "error": str(e)}))
+            return
+        except Exception as e:
+            log.exception("list all sessions failed")
+            self.set_status(502)
+            self.finish(json.dumps({"ok": False, "error": str(e)}))
+            return
+        self.finish(json.dumps({"ok": True, "sessions": sessions or []}))
+
+
+class NotebookSessionsHandler(APIHandler):
+    """Manage the list of sessions BOUND to one notebook.
+
+    GET    /opencode-bridge/sessions/notebook?notebook=...
+              -> { ok, activeSessionId, sessions: [{sessionId, title, ...}, ...] }
+                 The metadata (title, createdAt, ...) is enriched from
+                 OpenCode's `GET /session` so the frontend can render
+                 the picker without a second round-trip per session.
+    POST   /opencode-bridge/sessions/notebook?notebook=...&title=...
+              -> { ok, sessionId, activeSessionId } — creates a new
+                 session on OpenCode, binds it, sets as active.
+    PUT    /opencode-bridge/sessions/notebook?notebook=...&sessionId=...
+              -> { ok, sessionId, activeSessionId } — binds an
+                 existing sessionId (e.g. one the user picked from
+                 the global list) to this notebook and sets as active.
+    DELETE /opencode-bridge/sessions/notebook?notebook=...&sessionId=...
+              -> { ok, deleted } — deletes the session on OpenCode
+                 Serve AND removes its binding from this notebook.
+                 If it was the active one, clears active.
+    """
+
+    @tornado.web.authenticated
+    async def get(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        if not notebook_path:
+            self.set_status(400)
+            self.finish(json.dumps({"error": "missing 'notebook' query parameter"}))
+            return
+        sm = get_session_manager(self)
+        bound_ids = sm.list_sessions_for_notebook(notebook_path)
+        active = sm.get_active(notebook_path)
+        # Enrich with metadata from OpenCode Serve so the UI can show
+        # the title / createdAt without a second round-trip.
+        try:
+            all_sessions = await make_client(self).list_all_sessions()
+            by_id = {s.get("id"): s for s in (all_sessions or [])}
+        except Exception as e:
+            log.warning(
+                "could not enrich bound sessions with metadata: %s", e
+            )
+            by_id = {}
+        sessions = []
+        for sid in bound_ids:
+            meta = by_id.get(sid, {})
+            sessions.append({
+                "sessionId": sid,
+                "title": meta.get("title"),
+                "createdAt": meta.get("createdAt"),
+                "updatedAt": meta.get("updatedAt"),
+                "isActive": sid == active,
+            })
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "activeSessionId": active,
+            "sessions": sessions,
+        }))
+
+    @tornado.web.authenticated
+    async def post(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        if not notebook_path:
+            self.set_status(400)
+            self.finish(json.dumps({"error": "missing 'notebook' query parameter"}))
+            return
+        title = self.get_query_argument("title", None) or None
+        sm = get_session_manager(self)
+        try:
+            sid = await sm.create_new(notebook_path, title=title)
+        except OpenCodeError as e:
+            log.exception("create session failed")
+            self.set_status(502)
+            self.finish(json.dumps({"ok": False, "error": str(e)}))
+            return
+        except Exception as e:
+            log.exception("create session failed")
+            self.set_status(502)
+            self.finish(json.dumps({"ok": False, "error": str(e)}))
+            return
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "sessionId": sid,
+            "activeSessionId": sid,
+        }))
+
+    @tornado.web.authenticated
+    def put(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        session_id = self.get_query_argument("sessionId", "")
+        if not notebook_path or not session_id:
+            self.set_status(400)
+            self.finish(json.dumps({
+                "error": "missing 'notebook' and/or 'sessionId' query parameter"
+            }))
+            return
+        sm = get_session_manager(self)
+        sm.bind_existing(notebook_path, session_id)
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "sessionId": session_id,
+            "activeSessionId": sm.get_active(notebook_path),
+        }))
+
+    @tornado.web.authenticated
+    async def delete(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        session_id = self.get_query_argument("sessionId", "")
+        if not notebook_path or not session_id:
+            self.set_status(400)
+            self.finish(json.dumps({
+                "error": "missing 'notebook' and/or 'sessionId' query parameter"
+            }))
+            return
+        sm = get_session_manager(self)
+        deleted = await sm.delete_session(notebook_path, session_id)
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "sessionId": session_id,
+            "deleted": deleted,
+            "activeSessionId": sm.get_active(notebook_path),
+        }))
+
+
+class ActiveSessionHandler(APIHandler):
+    """Manage the ACTIVE session for one notebook.
+
+    GET    /opencode-bridge/sessions/active?notebook=...
+              -> { ok, activeSessionId, notebookPath }
+    PUT    /opencode-bridge/sessions/active?notebook=...&sessionId=...
+              -> { ok, activeSessionId } — switch the active bound
+                 session. sessionId MUST already be in the bound list.
+    DELETE /opencode-bridge/sessions/active?notebook=...
+              -> { ok } — unbind the active session (next /edit will
+                 lazy-create a new one). Does NOT delete the session
+                 on OpenCode Serve (use the notebook DELETE for that).
+    """
+
+    @tornado.web.authenticated
+    def get(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        if not notebook_path:
+            self.set_status(400)
+            self.finish(json.dumps({"error": "missing 'notebook' query parameter"}))
+            return
+        sm = get_session_manager(self)
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "activeSessionId": sm.get_active(notebook_path),
+        }))
+
+    @tornado.web.authenticated
+    def put(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        session_id = self.get_query_argument("sessionId", "")
+        if not notebook_path or not session_id:
+            self.set_status(400)
+            self.finish(json.dumps({
+                "error": "missing 'notebook' and/or 'sessionId' query parameter"
+            }))
+            return
+        sm = get_session_manager(self)
+        if not sm.set_active(notebook_path, session_id):
+            self.set_status(400)
+            self.finish(json.dumps({
+                "ok": False,
+                "error": "sessionId is not bound to this notebook; "
+                         "POST /sessions/notebook or PUT /sessions/notebook first"
+            }))
+            return
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "activeSessionId": sm.get_active(notebook_path),
+        }))
+
+    @tornado.web.authenticated
+    def delete(self):
+        notebook_path = self.get_query_argument("notebook", "")
+        if not notebook_path:
+            self.set_status(400)
+            self.finish(json.dumps({"error": "missing 'notebook' query parameter"}))
+            return
+        sm = get_session_manager(self)
+        sm.unbind_active(notebook_path)
+        self.finish(json.dumps({
+            "ok": True,
+            "notebookPath": notebook_path,
+            "activeSessionId": sm.get_active(notebook_path),
+        }))
+
+
 def setup_route_handlers(web_app):
     host_pattern = ".*$"
     base_url = web_app.settings["base_url"]
@@ -471,6 +682,10 @@ def setup_route_handlers(web_app):
         (url_path_join(base_url, "opencode-bridge", "sessions"), SessionListHandler),
         (url_path_join(base_url, "opencode-bridge", "session"), SessionReleaseHandler),
         (url_path_join(base_url, "opencode-bridge", "session-messages"), SessionMessagesHandler),
+        # Multi-session management (notebook can bind N sessions; one is active).
+        (url_path_join(base_url, "opencode-bridge", "sessions", "all"), AllSessionsListHandler),
+        (url_path_join(base_url, "opencode-bridge", "sessions", "notebook"), NotebookSessionsHandler),
+        (url_path_join(base_url, "opencode-bridge", "sessions", "active"), ActiveSessionHandler),
         # /permissions/<perm_id>  and  /questions/<q_id>/reply
         # use a URLSpec with a regex so the path param is forwarded to
         # the handler as a positional argument.

opencode_bridge/session_manager.py

@@ -1,13 +1,29 @@
 """Per-notebook session manager for OpenCode.
 
-Maps notebookPath -> OpenCode sessionID. Lazy create on first use.
+Maps each notebookPath to one OR MORE OpenCode session IDs. One of
-Async-safe via per-path asyncio.Lock. No automatic cleanup.
+the bound sessions is the "active" one (the one used for the next
+``/edit``). The others are historical — they were created in this
+notebook at some point but the user switched away (e.g. started a
+new conversation topic).
+
+Lifecycle:
+- ``get_or_create`` returns the active session, lazily creating one on
+  first use. This is the path used by ``EditHandler`` on every prompt.
+- ``create_new`` always creates a brand-new session on OpenCode Serve,
+  binds it, sets it as active. Used by the "New session" UI action.
+- ``bind_existing`` / ``set_active`` / ``unbind`` / ``delete_session``
+  are the management operations for the per-notebook session list.
+
+Async-safety: a per-notebook ``asyncio.Lock`` serializes
+``get_or_create`` so concurrent prompts on the same notebook don't
+double-create. The lock survives across calls (held in ``_locks``) so
+subsequent calls can reuse it.
 """
 from __future__ import annotations
 
 import asyncio
 import logging
-from typing import Callable
+from typing import Callable, Optional
 
 from .opencode_client import OpenCodeClient
 
@@ -17,81 +33,216 @@ ClientFactory = Callable[[], OpenCodeClient]
 
 
 class SessionManager:
-    """Tracks one OpenCode session per notebook path.
-
-    Threading/async model:
-      - Multiple coroutines may call get_or_create for the same notebook.
-      - First call creates; subsequent calls return the same sessionID.
-      - Per-notebook asyncio.Lock prevents double-create under concurrency.
-      - Locks remain in the map; they may be needed again for the same path.
-    """
-
     def __init__(self, client_factory: ClientFactory) -> None:
         self._client_factory = client_factory
-        self._sessions: dict[str, str] = {}        # notebookPath -> sessionID
+        # notebookPath -> active sessionId
-        self._locks: dict[str, asyncio.Lock] = {}  # notebookPath -> lock
+        self._active: dict[str, str] = {}
-        self._titles: dict[str, str] = {}         # notebookPath -> title (for debug)
+        # notebookPath -> ordered list of sessionIds bound to this
+        # notebook (the first is the oldest; the active one may be
+        # anywhere in the list). Used by the UI to render the session
+        # picker.
+        self._bound: dict[str, list[str]] = {}
+        # Per-notebook lock for serializing lazy-create.
+        self._locks: dict[str, asyncio.Lock] = {}
+
+    # ---------- active-session lookup / create ----------
 
     async def get_or_create(self, notebook_path: str) -> str:
-        """Return session ID for the notebook, creating one if needed.
+        """Return the active session id for this notebook, creating one
-
+        if no active session is bound yet. This is what ``EditHandler``
-        Idempotent for the same path. Different paths get different sessions.
+        calls on every prompt.
         """
-        existing = self._sessions.get(notebook_path)
+        active = self._active.get(notebook_path)
-        if existing is not None:
+        if active is not None:
-            return existing
+            return active
         lock = self._locks.setdefault(notebook_path, asyncio.Lock())
         async with lock:
-            existing = self._sessions.get(notebook_path)
+            active = self._active.get(notebook_path)
-            if existing is not None:
+            if active is not None:
-                return existing
+                return active
-            client = self._client_factory()
+            return await self._create_and_bind(notebook_path, title=None)
-            session = await client.create_session(
-                title="jupyter:%s" % notebook_path
-            )
-            sid = session["id"]
-            self._sessions[notebook_path] = sid
-            self._titles[notebook_path] = notebook_path
-            log.info("created opencode session %s for %s", sid, notebook_path)
-            return sid
 
-    async def release(self, notebook_path: str) -> bool:
+    async def _create_and_bind(
-        """Delete session and remove from map. Returns True if a session existed."""
+        self, notebook_path: str, title: Optional[str]
-        sid = self._sessions.pop(notebook_path, None)
+    ) -> str:
-        self._titles.pop(notebook_path, None)
+        client = self._client_factory()
-        self._locks.pop(notebook_path, None)
+        session = await client.create_session(
-        if sid is None:
+            title=title or "jupyter:%s" % notebook_path
+        )
+        sid = session["id"]
+        self._bind(notebook_path, sid)
+        log.info("created opencode session %s for %s", sid, notebook_path)
+        return sid
+
+    def get_active(self, notebook_path: str) -> Optional[str]:
+        """Return the active sessionId for the notebook, or None if no
+        active session has been bound/created yet. Does NOT create one.
+        """
+        return self._active.get(notebook_path)
+
+    def peek(self, notebook_path: str) -> Optional[str]:
+        """Alias for :meth:`get_active` (legacy name)."""
+        return self.get_active(notebook_path)
+
+    def has_session(self, notebook_path: str) -> bool:
+        """True iff at least one session has ever been bound to this
+        notebook (active or not)."""
+        return notebook_path in self._bound
+
+    # ---------- mutation: bind / unbind / set_active / create_new ----------
+
+    def _bind(self, notebook_path: str, session_id: str) -> None:
+        """Add session_id to the bound list (if not already) and set it
+        as active. Idempotent on re-bind.
+        """
+        self._active[notebook_path] = session_id
+        bound = self._bound.setdefault(notebook_path, [])
+        if session_id not in bound:
+            bound.append(session_id)
+
+    async def create_new(
+        self, notebook_path: str, title: Optional[str] = None
+    ) -> str:
+        """Create a brand new session on OpenCode Serve, bind it to
+        this notebook, set as active, return its id.
+        """
+        return await self._create_and_bind(notebook_path, title)
+
+    def bind_existing(self, notebook_path: str, session_id: str) -> None:
+        """Bind an existing sessionId to this notebook and set as active.
+        Does NOT call OpenCode — the caller must verify the session
+        exists (e.g. via ``GET /session``).
+        """
+        self._bind(notebook_path, session_id)
+
+    def set_active(self, notebook_path: str, session_id: str) -> bool:
+        """Switch the active session. Returns False if ``session_id`` is
+        not currently bound to this notebook (callers should bind first
+        if uncertain).
+        """
+        bound = self._bound.get(notebook_path, [])
+        if session_id not in bound:
+            return False
+        self._active[notebook_path] = session_id
+        return True
+
+    def unbind(self, notebook_path: str, session_id: str) -> bool:
+        """Remove ``session_id`` from this notebook's bindings. If it was
+        the active one, also clear active (next prompt will lazy-create
+        a new session). Returns True if it was bound.
+        """
+        bound = self._bound.get(notebook_path)
+        if not bound or session_id not in bound:
+            return False
+        bound.remove(session_id)
+        if self._active.get(notebook_path) == session_id:
+            self._active.pop(notebook_path, None)
+        if not bound:
+            self._bound.pop(notebook_path, None)
+        return True
+
+    def unbind_active(self, notebook_path: str) -> bool:
+        """Remove the active session binding only (leaves the rest of
+        the notebook's bound sessions intact). Next prompt will
+        lazy-create a new active session. Returns True if there was an
+        active binding to remove.
+        """
+        active = self._active.pop(notebook_path, None)
+        if active is None:
+            return False
+        bound = self._bound.get(notebook_path)
+        if bound is not None:
+            bound.remove(active)
+            if not bound:
+                self._bound.pop(notebook_path, None)
+        return True
+
+    async def delete_session(
+        self, notebook_path: str, session_id: str
+    ) -> bool:
+        """Delete the session on OpenCode Serve AND remove its binding.
+
+        Order matters: we ask OpenCode to delete FIRST, and only remove
+        the local binding if OpenCode confirmed the delete. That way a
+        failed delete leaves the binding intact (the user can retry);
+        a deleted session never leaves a phantom binding behind.
+
+        Returns True if the session was actually deleted (i.e. it was
+        bound AND OpenCode acknowledged the delete). If the session is
+        not bound to this notebook, do NOT call OpenCode (we don't
+        want to silently delete sessions owned by other tools).
+        """
+        if not self._is_bound(notebook_path, session_id):
             return False
         try:
             client = self._client_factory()
-            return await client.delete_session(sid)
+            deleted = await client.delete_session(session_id)
         except Exception:
-            log.warning(
+            log.warning("failed to delete opencode session %s", session_id)
-                "failed to delete opencode session %s for %s", sid, notebook_path
-            )
             return False
+        # Whether the delete succeeded or just returned False (404), the
+        # session is gone on the OpenCode side — drop the binding to
+        # keep the UI consistent. We return whether OpenCode said
+        # "yes" so the caller can surface a warning on a 404.
+        self.unbind(notebook_path, session_id)
+        return deleted
+
+    def _is_bound(self, notebook_path: str, session_id: str) -> bool:
+        bound = self._bound.get(notebook_path)
+        return bool(bound) and session_id in bound
+
+    # ---------- legacy / compat ----------
+
+    async def release(self, notebook_path: str) -> bool:
+        """Tear down ALL state for this notebook: delete every bound
+        session on OpenCode Serve AND clear every local binding.
+        Returns True iff at least one session was actually deleted
+        on the OpenCode side. (For deleting a SPECIFIC session use
+        :meth:`delete_session`.)
+        """
+        bound = list(self._bound.get(notebook_path, []))
+        deleted_any = False
+        for sid in bound:
+            if await self.delete_session(notebook_path, sid):
+                deleted_any = True
+        # `delete_session` clears the binding. Belt-and-suspenders: drop
+        # any straggler state.
+        self._bound.pop(notebook_path, None)
+        self._active.pop(notebook_path, None)
+        self._locks.pop(notebook_path, None)
+        return deleted_any
 
     def invalidate(self, notebook_path: str) -> bool:
-        """Drop the cached sessionID without calling OpenCode. Returns True if removed.
+        """Drop the cached active sessionId without calling OpenCode.
-
+        Returns True if a binding was removed. Use this when an
-        Use this when an upstream error indicates the session is dead (e.g., 404).
+        upstream error indicates the session is dead (e.g. 404).
         """
-        sid = self._sessions.pop(notebook_path, None)
+        was_active = self._active.pop(notebook_path, None)
-        self._titles.pop(notebook_path, None)
+        if was_active is None:
-        return sid is not None
+            return False
-
+        bound = self._bound.get(notebook_path)
-    def has_session(self, notebook_path: str) -> bool:
+        if bound is not None:
-        return notebook_path in self._sessions
+            try:
-
+                bound.remove(was_active)
-    def peek(self, notebook_path: str) -> Optional[str]:
+            except ValueError:
-        """Return the cached sessionID for the notebook, or None if no
+                pass
-        session has been created yet. Does NOT create one (unlike
+            if not bound:
-        get_or_create) — used by the history endpoint to avoid spawning
+                self._bound.pop(notebook_path, None)
-        a session just to report that there is none."""
+        return True
-        return self._sessions.get(notebook_path)
 
     def list_sessions(self) -> list[dict]:
+        """Debug: list all (notebookPath, activeSessionId) pairs across
+        every notebook. One row per notebook — does NOT enumerate the
+        full bound-list per notebook. Use
+        :meth:`list_sessions_for_notebook` for that.
+        """
         return [
             {"notebookPath": path, "sessionId": sid}
-            for path, sid in sorted(self._sessions.items())
+            for path, sid in sorted(self._active.items())
         ]
+
+    def list_sessions_for_notebook(self, notebook_path: str) -> list[str]:
+        """All sessionIds bound to this notebook (in bind order: oldest
+        first, newest last). Empty list if none.
+        """
+        return list(self._bound.get(notebook_path, []))

opencode_bridge/tests/test_client.py

@@ -266,6 +266,22 @@ async def test_reply_question_posts_answer(base_config: OpenCodeConfig) -> None:
     assert body == {"answer": "use 3.12"}
 
 
+@pytest.mark.asyncio
+async def test_list_all_sessions_gets_session(base_config: OpenCodeConfig) -> None:
+    """list_all_sessions proxies OpenCode Serve's GET /session and returns
+    the raw list (no projection)."""
+    payload = [
+        {"id": "s1", "title": "first", "createdAt": 1, "updatedAt": 2},
+        {"id": "s2", "title": "second", "createdAt": 3, "updatedAt": 4},
+    ]
+    client, mock = _make_client(base_config, [(200, payload)])
+    sessions = await client.list_all_sessions()
+    assert sessions == payload
+    call = mock.calls[0]
+    assert call["request"].url == "http://127.0.0.1:4096/session"
+    assert call["request"].method == "GET"
+
+
 @pytest.mark.asyncio
 async def test_non_2xx_response_raises_with_body(base_config: OpenCodeConfig) -> None:
     client, mock = _make_client(base_config, [(500, {"error": "boom"})])

opencode_bridge/tests/test_routes.py

@@ -57,6 +57,29 @@ class FakeOpenCodeClient:
         self.calls.append(("list_session_messages", session_id))
         return self.messages_response
 
+    async def list_all_sessions(self):
+        self.calls.append(("list_all_sessions",))
+        return [
+            {
+                "id": "fake-session-123",
+                "title": "jupyter:foo.ipynb",
+                "createdAt": 1700000000000,
+                "updatedAt": 1700000001000,
+            },
+            {
+                "id": "other-session",
+                "title": "manual session",
+                "createdAt": 1700000010000,
+                "updatedAt": 1700000011000,
+            },
+        ]
+
+    async def create_session(self, title):
+        self.calls.append(("create_session", title))
+        # Return a fresh id (different from the default "fake-session-123").
+        new_id = "newly-created-" + title
+        return {"id": new_id, "title": title}
+
     async def reply_permission(self, session_id, permission_id, response):
         self.calls.append(("reply_permission", session_id, permission_id, response))
         return True
@@ -72,35 +95,84 @@ class FakeOpenCodeClient:
 
 
 class FakeSessionManager:
-    """Drop-in replacement for SessionManager with recording."""
+    """Thin wrapper around the real SessionManager with a recording
+    ``FakeOpenCodeClient``. Lets route tests exercise the real
+    multi-session logic without touching OpenCode.
+    """
 
-    def __init__(self, session_id: str = "fake-session-123") -> None:
+    def __init__(self, session_id: str = "fake-session-123", client=None) -> None:
-        self._session_id = session_id
+        from opencode_bridge.session_manager import SessionManager
-        self.calls: list = []
+        # `_client` attribute used by some legacy tests. Allow injection
+        # so a test can share its FakeOpenCodeClient with the SessionManager
+        # (the real SessionManager calls into its own client_factory, NOT
+        # the route's make_client).
+        self._client = client if client is not None else FakeOpenCodeClient()
+        self._sm = SessionManager(lambda: self._client)
+        self.calls: list = self._client.calls
+        # Legacy attribute used by list_sessions() etc.
+        self._sessions: dict = {}
 
-    async def get_or_create(self, notebook_path: str) -> str:
+    # ---- delegation to the real SessionManager ----
-        self.calls.append(("get_or_create", notebook_path))
+    def _record(self, name, *args):
-        return self._session_id
+        self.calls.append((name, *args))
+        return None
+
+    def get_or_create(self, notebook_path: str):
+        self._record("get_or_create", notebook_path)
+        return self._sm.get_or_create(notebook_path)
 
     def peek(self, notebook_path: str):
-        # Mirror SessionManager.peek: return the session id without
+        return self._sm.peek(notebook_path)
-        # creating one. None means "no session yet" (used by the no-session
-        # test to short-circuit the history route).
-        return self._session_id or None
 
-    async def release(self, notebook_path: str) -> bool:
+    def get_active(self, notebook_path: str):
-        self.calls.append(("release", notebook_path))
+        return self._sm.get_active(notebook_path)
-        return True
 
     def list_sessions(self) -> list:
-        return [
+        return self._sm.list_sessions()
-            {"notebookPath": path, "sessionId": sid}
+
-            for path, sid in sorted(self._sessions.items())
+    def list_sessions_for_notebook(self, notebook_path: str):
-        ]
+        return self._sm.list_sessions_for_notebook(notebook_path)
+
+    def bind_existing(self, notebook_path: str, session_id: str) -> None:
+        self._record("bind_existing", notebook_path, session_id)
+        self._sm.bind_existing(notebook_path, session_id)
+
+    def set_active(self, notebook_path: str, session_id: str) -> bool:
+        self._record("set_active", notebook_path, session_id)
+        return self._sm.set_active(notebook_path, session_id)
+
+    def unbind(self, notebook_path: str, session_id: str) -> bool:
+        self._record("unbind", notebook_path, session_id)
+        return self._sm.unbind(notebook_path, session_id)
+
+    def unbind_active(self, notebook_path: str) -> bool:
+        self._record("unbind_active", notebook_path)
+        return self._sm.unbind_active(notebook_path)
 
     def invalidate(self, notebook_path: str) -> bool:
-        self.calls.append(("invalidate", notebook_path))
+        self._record("invalidate", notebook_path)
-        return True
+        return self._sm.invalidate(notebook_path)
+
+    async def release(self, notebook_path: str) -> bool:
+        self._record("release", notebook_path)
+        return await self._sm.release(notebook_path)
+
+    async def delete_session(self, notebook_path: str, session_id: str) -> bool:
+        self._record("delete_session", notebook_path, session_id)
+        return await self._sm.delete_session(notebook_path, session_id)
+
+    async def create_new(self, notebook_path: str, title: str | None = None) -> str:
+        self._record("create_new", notebook_path, title)
+        return await self._sm.create_new(notebook_path, title)
+
+    # ---- internal-state proxies (used by tests that poke internals) ----
+    @property
+    def _active(self) -> dict:
+        return self._sm._active
+
+    @property
+    def _bound(self) -> dict:
+        return self._sm._bound
 
 
 async def test_hello(jp_fetch):
@@ -178,11 +250,11 @@ async def test_edit_handler(monkeypatch, jp_fetch):
     )
     assert response.code == 200
     payload = json.loads(response.body)
-    assert payload == {
+    # The exact sessionId comes from the FakeClient; just check the
-        "ok": True,
+    # shape — keys are present and ok is true.
-        "sessionId": "fake-session-123",
+    assert payload["ok"] is True
-        "notebookPath": "test.ipynb",
+    assert isinstance(payload["sessionId"], str) and payload["sessionId"]
-    }
+    assert payload["notebookPath"] == "test.ipynb"
     # Async path: no `markdown` field. The LLM reply is consumed via SSE.
     assert "markdown" not in payload
 
@@ -193,16 +265,21 @@ async def test_edit_handler(monkeypatch, jp_fetch):
     assert "send_message_async" in call_names
     assert "send_message_sync" not in call_names  # legacy sync path is gone
 
-    # send_message_async received the session ID from the manager.
+    # send_message_async received a session id from the manager (the
+    # exact value comes from the FakeClient; just verify it matches
+    # the response's sessionId).
     send_call = [c for c in fake.calls if c[0] == "send_message_async"][0]
-    assert send_call[1] == "fake-session-123"
+    assert send_call[1] == payload["sessionId"]
     # system prompt was passed.
     assert "你是一个代码助手" in send_call[3]
 
     # SessionManager.get_or_create was called with the notebook path.
+    # (The real SessionManager internally calls create_session on the
+    # FakeClient too, so the shared calls list has both entries.)
     sm_call_names = [c[0] for c in fake_sm.calls]
-    assert sm_call_names == ["get_or_create"]
+    assert "get_or_create" in sm_call_names
-    assert fake_sm.calls[0][1] == "test.ipynb"
+    get_or_create_call = [c for c in fake_sm.calls if c[0] == "get_or_create"][0]
+    assert get_or_create_call[1] == "test.ipynb"
 
 
 async def test_edit_handler_includes_model_when_provider_and_model_given(
@@ -242,10 +319,12 @@ async def test_edit_handler_includes_model_when_provider_and_model_given(
 
 async def test_session_list_handler(monkeypatch, jp_fetch):
     fake_sm = FakeSessionManager()
-    fake_sm._sessions = {
+    # Seed the underlying real SessionManager's state so list_sessions
-        "foo.ipynb": "sid-1",
+    # returns the expected debug mapping.
-        "bar.ipynb": "sid-2",
+    fake_sm._active["foo.ipynb"] = "sid-1"
-    }  # direct injection
+    fake_sm._active["bar.ipynb"] = "sid-2"
+    fake_sm._bound["foo.ipynb"] = ["sid-1"]
+    fake_sm._bound["bar.ipynb"] = ["sid-2"]
     monkeypatch.setattr(
         "opencode_bridge.routes.get_session_manager", lambda h: fake_sm
     )
@@ -290,6 +369,10 @@ async def test_session_messages_handler_projects_opencode_messages(
     monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
 
     fake_sm = FakeSessionManager(session_id="fake-session-123")
+    # Seed the bound state so peek() returns the session id (the route
+    # only fetches messages if there's an active session).
+    fake_sm._active["test.ipynb"] = "fake-session-123"
+    fake_sm._bound["test.ipynb"] = ["fake-session-123"]
     monkeypatch.setattr(
         "opencode_bridge.routes.get_session_manager", lambda h: fake_sm
     )
@@ -332,6 +415,11 @@ async def test_session_release_handler(monkeypatch, jp_fetch):
         "opencode_bridge.routes.get_session_manager", lambda h: fake_sm
     )
 
+    # Set up state: get_or_create actually binds a session to the
+    # notebook in the real SessionManager (via the FakeClient). release
+    # then has something to delete.
+    await fake_sm.get_or_create("foo.ipynb")
+
     response = await jp_fetch(
         "opencode-bridge", "session",
         method="DELETE",
@@ -459,3 +547,221 @@ async def test_global_event_handler_forwards_all_events_unfiltered(
     assert '"server.connected"' in body
     # The body should use the SSE format: each event as a `data:` line.
     assert body.count("data: ") == 3
+
+
+# ---------------------------------------------------------------------------
+# Multi-session management endpoints
+# ---------------------------------------------------------------------------
+
+
+async def test_all_sessions_handler_returns_global_list(monkeypatch, jp_fetch):
+    """GET /sessions/all proxies OpenCode Serve's GET /session."""
+    fake = FakeOpenCodeClient()
+    monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
+    response = await jp_fetch("opencode-bridge", "sessions", "all")
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["ok"] is True
+    assert len(payload["sessions"]) == 2
+    # The fake returns both the default session and a hand-rolled "other-session".
+    ids = {s["id"] for s in payload["sessions"]}
+    assert "fake-session-123" in ids
+    assert "other-session" in ids
+    assert ("list_all_sessions",) in fake.calls
+
+
+async def test_notebook_sessions_get_returns_bound_with_metadata(
+    monkeypatch, jp_fetch
+):
+    """GET /sessions/notebook?notebook=... returns the bound sessions
+    enriched with title/createdAt from the global list."""
+    fake = FakeOpenCodeClient()
+    monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
+    sm = FakeSessionManager()
+    sm._active["foo.ipynb"] = "fake-session-123"
+    sm._bound["foo.ipynb"] = ["fake-session-123"]
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "notebook",
+        params={"notebook": "foo.ipynb"},
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["notebookPath"] == "foo.ipynb"
+    assert payload["activeSessionId"] == "fake-session-123"
+    assert len(payload["sessions"]) == 1
+    s = payload["sessions"][0]
+    assert s["sessionId"] == "fake-session-123"
+    assert s["title"] == "jupyter:foo.ipynb"
+    assert s["isActive"] is True
+
+
+async def test_notebook_sessions_post_creates_and_binds(monkeypatch, jp_fetch):
+    """POST /sessions/notebook creates a new session on OpenCode and
+    binds it as active."""
+    fake = FakeOpenCodeClient()
+    monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
+    # Share the client with the SessionManager so the test can assert
+    # against `fake.calls` (the real SessionManager calls its own
+    # client_factory, NOT the route's make_client).
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager",
+        lambda h: FakeSessionManager(client=fake),
+    )
+
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "notebook",
+        method="POST",
+        params={"notebook": "foo.ipynb", "title": "fresh"},
+        body=json.dumps({}),
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["ok"] is True
+    assert payload["sessionId"] == "newly-created-fresh"
+    # The new session is the active one.
+    assert payload["activeSessionId"] == "newly-created-fresh"
+    # OpenCode was called.
+    assert ("create_session", "fresh") in fake.calls
+
+
+async def test_notebook_sessions_put_binds_existing(monkeypatch, jp_fetch):
+    """PUT /sessions/notebook binds an existing sessionId without
+    calling OpenCode. Sets it as active."""
+    fake = FakeOpenCodeClient()
+    monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
+    sm = FakeSessionManager()
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "notebook",
+        method="PUT",
+        params={"notebook": "foo.ipynb", "sessionId": "some-existing-sid"},
+        body=json.dumps({}),
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["sessionId"] == "some-existing-sid"
+    assert payload["activeSessionId"] == "some-existing-sid"
+    # No OpenCode round-trip for the bind.
+    assert ("create_session", ...) not in [
+        c for c in fake.calls if c[0] == "create_session"
+    ]
+
+
+async def test_active_session_set_requires_bound(monkeypatch, jp_fetch):
+    """PUT /sessions/active?sessionId=X fails with 400 if X is not bound."""
+    monkeypatch.setattr(
+        "opencode_bridge.routes.make_client", lambda h: FakeOpenCodeClient()
+    )
+    sm = FakeSessionManager()
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+    with pytest.raises(tornado.httpclient.HTTPClientError) as exc_info:
+        await jp_fetch(
+            "opencode-bridge", "sessions", "active",
+            method="PUT",
+            params={"notebook": "foo.ipynb", "sessionId": "never-bound"},
+            body=json.dumps({}),
+        )
+    assert exc_info.value.code == 400
+
+
+async def test_active_session_set_switches(monkeypatch, jp_fetch):
+    """PUT /sessions/active successfully switches when the sessionId is bound."""
+    monkeypatch.setattr(
+        "opencode_bridge.routes.make_client", lambda h: FakeOpenCodeClient()
+    )
+    sm = FakeSessionManager()
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "active",
+        method="PUT",
+        params={"notebook": "foo.ipynb", "sessionId": "sid-A"},
+        body=json.dumps({}),
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["activeSessionId"] == "sid-A"
+
+
+async def test_active_session_delete_unbinds_only(monkeypatch, jp_fetch):
+    """DELETE /sessions/active unbinds the active session; other
+    bound sessions are kept; OpenCode is NOT called."""
+    fake = FakeOpenCodeClient()
+    monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
+    sm = FakeSessionManager()
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "active",
+        method="DELETE",
+        params={"notebook": "foo.ipynb"},
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["activeSessionId"] is None
+    # sid-A is still bound; sid-B was the active and is gone.
+    assert sm.list_sessions_for_notebook("foo.ipynb") == ["sid-A"]
+    # No OpenCode call.
+    assert not any(c[0] == "delete_session" for c in fake.calls)
+
+
+async def test_active_session_get_returns_id_or_null(monkeypatch, jp_fetch):
+    monkeypatch.setattr(
+        "opencode_bridge.routes.make_client", lambda h: FakeOpenCodeClient()
+    )
+    sm = FakeSessionManager()
+    sm.bind_existing("foo.ipynb", "sid-A")
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "active",
+        params={"notebook": "foo.ipynb"},
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["activeSessionId"] == "sid-A"
+
+
+async def test_notebook_sessions_delete_removes_session(monkeypatch, jp_fetch):
+    """DELETE /sessions/notebook?notebook=...&sessionId=... deletes
+    the session on OpenCode AND removes its binding."""
+    fake = FakeOpenCodeClient()
+    monkeypatch.setattr("opencode_bridge.routes.make_client", lambda h: fake)
+    # Share the client with the SessionManager so the test can assert
+    # against `fake.calls` (the real SessionManager calls its own
+    # client_factory, NOT the route's make_client).
+    sm = FakeSessionManager(client=fake)
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    monkeypatch.setattr(
+        "opencode_bridge.routes.get_session_manager", lambda h: sm
+    )
+    response = await jp_fetch(
+        "opencode-bridge", "sessions", "notebook",
+        method="DELETE",
+        params={"notebook": "foo.ipynb", "sessionId": "sid-A"},
+    )
+    assert response.code == 200
+    payload = json.loads(response.body)
+    assert payload["deleted"] is True
+    # OpenCode delete was called for sid-A.
+    assert ("delete_session", "sid-A") in fake.calls
+    # sid-A is gone; sid-B remains active.
+    assert sm.list_sessions_for_notebook("foo.ipynb") == ["sid-B"]
+    assert sm.get_active("foo.ipynb") == "sid-B"

opencode_bridge/tests/test_session_manager.py

@@ -7,13 +7,31 @@ from opencode_bridge.session_manager import SessionManager
 
 
 class FakeClient:
-    """Mimics OpenCodeClient just enough for SessionManager."""
+    """Mimics OpenCodeClient just enough for SessionManager.
-    def __init__(self, session_id: str = "sid-from-fake") -> None:
+
+    By default returns the same id for every create_session call
+    (matching the original legacy behavior; several pre-existing tests
+    rely on that). Tests that need a fresh id per call should set
+    ``unique_ids_per_call=True`` in the constructor.
+    """
+    def __init__(
+        self,
+        session_id: str = "sid-from-fake",
+        unique_ids_per_call: bool = False,
+    ) -> None:
         self._session_id = session_id
+        self._unique_ids = unique_ids_per_call
+        self._next_id = 0
         self.calls: list = []
 
     async def create_session(self, title: str) -> dict:
         self.calls.append(("create_session", title))
+        if self._unique_ids:
+            self._next_id += 1
+            return {
+                "id": "%s-%d" % (self._session_id, self._next_id),
+                "title": title,
+            }
         return {"id": self._session_id, "title": title}
 
     async def delete_session(self, session_id: str) -> bool:
@@ -112,7 +130,7 @@ async def test_list_sessions_returns_all_mappings():
     sm = SessionManager(lambda: client)
     await sm.get_or_create("a.ipynb")
     # Manually inject a second to test listing
-    sm._sessions["b.ipynb"] = "sid-b"
+    sm._active["b.ipynb"] = "sid-b"
     listing = sm.list_sessions()
     paths = {s["notebookPath"] for s in listing}
     assert paths == {"a.ipynb", "b.ipynb"}
@@ -133,3 +151,147 @@ async def test_concurrent_get_or_create_does_not_double_create():
     assert sids[0] == sids[1] == sids[2]
     create_calls = [c for c in client.calls if c[0] == "create_session"]
     assert len(create_calls) == 1, "concurrent get_or_create must not double-create"
+
+
+# ---------------------------------------------------------------------------
+# Multi-session: 1 notebook can bind N sessions, one is active
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.asyncio
+async def test_create_new_binds_and_makes_active():
+    client = FakeClient(unique_ids_per_call=True)
+    sm = SessionManager(lambda: client)
+    sid = await sm.create_new("foo.ipynb", title="custom")
+    assert sid == "sid-from-fake-1"
+    # New session is the active one and the only bound one.
+    assert sm.get_active("foo.ipynb") == sid
+    assert sm.list_sessions_for_notebook("foo.ipynb") == [sid]
+
+
+@pytest.mark.asyncio
+async def test_create_new_when_active_exists_keeps_old_bound():
+    client = FakeClient(unique_ids_per_call=True)
+    sm = SessionManager(lambda: client)
+    first = await sm.get_or_create("foo.ipynb")
+    second = await sm.create_new("foo.ipynb")
+    # Two distinct session ids.
+    assert first != second
+    assert first == "sid-from-fake-1"
+    assert second == "sid-from-fake-2"
+    # Both are bound; the new one is active.
+    bound = sm.list_sessions_for_notebook("foo.ipynb")
+    assert set(bound) == {first, second}
+    assert sm.get_active("foo.ipynb") == second
+    # get_or_create still returns the active one (does NOT auto-pick the latest).
+    assert await sm.get_or_create("foo.ipynb") == second
+
+
+def test_bind_existing_does_not_call_opencode():
+    client = FakeClient()
+    sm = SessionManager(lambda: client)
+    sm.bind_existing("foo.ipynb", "sid-from-list")
+    assert client.calls == []  # no OpenCode round-trip
+    assert sm.get_active("foo.ipynb") == "sid-from-list"
+    assert "sid-from-list" in sm.list_sessions_for_notebook("foo.ipynb")
+
+
+def test_set_active_requires_session_to_be_bound():
+    sm = SessionManager(lambda: FakeClient())
+    sm.bind_existing("foo.ipynb", "sid-A")
+    assert sm.set_active("foo.ipynb", "sid-A") is True
+    # Switching to a session that is NOT bound must fail.
+    assert sm.set_active("foo.ipynb", "sid-UNKNOWN") is False
+    # Active didn't change.
+    assert sm.get_active("foo.ipynb") == "sid-A"
+
+
+def test_unbind_removes_from_bound_and_clears_active_if_was_active():
+    sm = SessionManager(lambda: FakeClient())
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    # B is the active one (last bind wins). Unbind B.
+    assert sm.get_active("foo.ipynb") == "sid-B"
+    assert sm.unbind("foo.ipynb", "sid-B") is True
+    # Active falls back to None (no other session auto-promotes).
+    assert sm.get_active("foo.ipynb") is None
+    assert sm.list_sessions_for_notebook("foo.ipynb") == ["sid-A"]
+
+
+def test_unbind_non_active_leaves_active_intact():
+    sm = SessionManager(lambda: FakeClient())
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    assert sm.get_active("foo.ipynb") == "sid-B"
+    # Unbind A (not the active one).
+    assert sm.unbind("foo.ipynb", "sid-A") is True
+    # Active is still B.
+    assert sm.get_active("foo.ipynb") == "sid-B"
+
+
+def test_unbind_active_keeps_other_sessions():
+    sm = SessionManager(lambda: FakeClient())
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    sm.unbind_active("foo.ipynb")
+    assert sm.get_active("foo.ipynb") is None
+    # B is gone from the bound list; A remains.
+    assert "sid-A" in sm.list_sessions_for_notebook("foo.ipynb")
+    assert "sid-B" not in sm.list_sessions_for_notebook("foo.ipynb")
+
+
+@pytest.mark.asyncio
+async def test_delete_session_unbinds_and_calls_opencode():
+    client = FakeClient()
+    sm = SessionManager(lambda: client)
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    deleted = await sm.delete_session("foo.ipynb", "sid-A")
+    assert deleted is True
+    # OpenCode was called.
+    assert any(
+        c[0] == "delete_session" and c[1] == "sid-A" for c in client.calls
+    )
+    # sid-A is gone from bindings; sid-B remains as active.
+    assert "sid-A" not in sm.list_sessions_for_notebook("foo.ipynb")
+    assert sm.get_active("foo.ipynb") == "sid-B"
+
+
+@pytest.mark.asyncio
+async def test_delete_session_not_bound_returns_false():
+    client = FakeClient()
+    sm = SessionManager(lambda: client)
+    assert await sm.delete_session("foo.ipynb", "never-bound") is False
+    # No OpenCode call.
+    assert not any(c[0] == "delete_session" for c in client.calls)
+
+
+@pytest.mark.asyncio
+async def test_release_drops_all_bindings_and_deletes_active():
+    client = FakeClient()
+    sm = SessionManager(lambda: client)
+    sm.bind_existing("foo.ipynb", "sid-A")
+    sm.bind_existing("foo.ipynb", "sid-B")
+    ok = await sm.release("foo.ipynb")
+    assert ok is True
+    # OpenCode delete called for the active one (sid-B).
+    assert any(
+        c[0] == "delete_session" and c[1] == "sid-B" for c in client.calls
+    )
+    # Both bindings cleared.
+    assert sm.list_sessions_for_notebook("foo.ipynb") == []
+    assert sm.get_active("foo.ipynb") is None
+
+
+@pytest.mark.asyncio
+async def test_get_or_create_after_set_active_returns_the_active_one():
+    client = FakeClient()
+    sm = SessionManager(lambda: client)
+    first = await sm.get_or_create("foo.ipynb")
+    sm.bind_existing("foo.ipynb", "another-sid")
+    sm.set_active("foo.ipynb", "another-sid")
+    # Next /edit-style call returns the manually-set active session.
+    assert await sm.get_or_create("foo.ipynb") == "another-sid"
+    # No additional create_session call.
+    creates = [c for c in client.calls if c[0] == "create_session"]
+    assert len(creates) == 1  # only the initial get_or_create

package.json

@@ -1,6 +1,6 @@
 {
     "name": "opencode_bridge",
-    "version": "0.1.0",
+    "version": "0.1.1",
     "description": "A JupyterLab extension.",
     "keywords": [
         "jupyter",

src/__tests__/cell_context.spec.ts

@@ -1,154 +0,0 @@
-import type { CodeCell, ICodeCellModel } from '@jupyterlab/cells';
-import type { NotebookPanel } from '@jupyterlab/notebook';
-
-import { collectErrorOutputs, extractCellContext } from '../context/cell_context';
-
-function makeMockOutputs(items: unknown[]): ICodeCellModel['outputs'] {
-  return {
-    get length() {
-      return items.length;
-    },
-    get(i: number) {
-      return items[i];
-    },
-    // Other IObservableList methods are unused in collectErrorOutputs.
-  } as unknown as ICodeCellModel['outputs'];
-}
-
-function makeMockModel(overrides: {
-  id?: string;
-  type?: 'code' | 'markdown' | 'raw';
-  source?: string;
-  outputs?: unknown[];
-}): ICodeCellModel {
-  return {
-    id: overrides.id ?? 'cell-1',
-    type: overrides.type ?? 'code',
-    sharedModel: {
-      getSource: () => overrides.source ?? '',
-    },
-    outputs: makeMockOutputs(overrides.outputs ?? []),
-  } as unknown as ICodeCellModel;
-}
-
-function makeMockCell(source: string, errorOutputs: unknown[] = []): CodeCell {
-  return { model: makeMockModel({ source, outputs: errorOutputs }) } as CodeCell;
-}
-
-function makeMockNotebook(cells: CodeCell[]): { widgets: CodeCell[] } {
-  return { widgets: cells };
-}
-
-function makeMockPanel(
-  notebook: { widgets: CodeCell[] },
-  path: string
-): NotebookPanel {
-  return {
-    context: { path } as NotebookPanel['context'],
-    content: notebook as unknown as NotebookPanel['content'],
-  } as unknown as NotebookPanel;
-}
-
-describe('collectErrorOutputs', () => {
-  it('returns null when there are no outputs', () => {
-    const model = makeMockModel({ outputs: [] });
-    expect(collectErrorOutputs(model)).toBeNull();
-  });
-
-  it('returns null when outputs are non-error', () => {
-    const model = makeMockModel({
-      outputs: [{ type: 'stream', text: 'hello' }],
-    });
-    expect(collectErrorOutputs(model)).toBeNull();
-  });
-
-  it('extracts the first error output', () => {
-    const errOut = {
-      type: 'error',
-      ename: 'ValueError',
-      evalue: 'bad value',
-      traceback: ['line 1', 'line 2'],
-    };
-    const model = makeMockModel({ outputs: [errOut] });
-    const result = collectErrorOutputs(model);
-    expect(result).toEqual({
-      ename: 'ValueError',
-      evalue: 'bad value',
-      traceback: ['line 1', 'line 2'],
-    });
-  });
-
-  it('handles missing traceback gracefully', () => {
-    const model = makeMockModel({
-      outputs: [{ type: 'error', ename: 'E', evalue: 'v' }],
-    });
-    const result = collectErrorOutputs(model);
-    expect(result?.traceback).toEqual([]);
-  });
-});
-
-describe('extractCellContext', () => {
-  it('returns null when cell is not in notebook', () => {
-    const cell = makeMockCell('x = 1');
-    const other = makeMockCell('y = 2');
-    const notebook = makeMockNotebook([other]);
-    const panel = makeMockPanel(notebook, 'foo.ipynb');
-    expect(extractCellContext(cell, panel)).toBeNull();
-  });
-
-  it('extracts source, language, and indices', () => {
-    const cell = makeMockCell('x = 1');
-    const notebook = makeMockNotebook([cell]);
-    const panel = makeMockPanel(notebook, 'foo.ipynb');
-    const ctx = extractCellContext(cell, panel);
-    expect(ctx).toMatchObject({
-      notebookPath: 'foo.ipynb',
-      cellId: 'cell-1',
-      language: 'python',
-      cellIndex: 0,
-      totalCells: 1,
-      source: 'x = 1',
-      previousCode: null,
-      error: null,
-    });
-  });
-
-  it('captures the previous cell source as previousCode', () => {
-    const prev = makeMockCell('import os');
-    const cell = makeMockCell('os.getcwd()');
-    const notebook = makeMockNotebook([prev, cell]);
-    const panel = makeMockPanel(notebook, 'foo.ipynb');
-    const ctx = extractCellContext(cell, panel);
-    expect(ctx?.previousCode).toBe('import os');
-    expect(ctx?.cellIndex).toBe(1);
-    expect(ctx?.totalCells).toBe(2);
-  });
-
-  it('includes the error when the cell has an error output', () => {
-    const cell = makeMockCell('1/0', [
-      {
-        type: 'error',
-        ename: 'ZeroDivisionError',
-        evalue: 'division by zero',
-        traceback: ['Traceback...'],
-      },
-    ]);
-    const notebook = makeMockNotebook([cell]);
-    const panel = makeMockPanel(notebook, 'foo.ipynb');
-    const ctx = extractCellContext(cell, panel);
-    expect(ctx?.error).toEqual({
-      ename: 'ZeroDivisionError',
-      evalue: 'division by zero',
-      traceback: ['Traceback...'],
-    });
-  });
-
-  it('returns null when given null cell or panel', () => {
-    expect(
-      extractCellContext(
-        null as unknown as CodeCell,
-        makeMockPanel(makeMockNotebook([]), 'x.ipynb')
-      )
-    ).toBeNull();
-  });
-});

src/__tests__/opencode_client.spec.ts

@@ -72,15 +72,8 @@ function mockResponse(overrides: {
 const sampleRequest: OpenCodeRequest = {
   prompt: 'add type hints',
   context: {
-    notebookPath: 'foo.ipynb',
+    notebookPath: 'foo.ipynb'
-    cellId: 'cell-1',
+  }
-    language: 'python',
-    cellIndex: 0,
-    totalCells: 1,
-    source: 'def foo(x): return x',
-    previousCode: null,
-    error: null,
-  },
 };
 
 describe('callOpenCodeEdit', () => {

src/api/opencode_client.ts

@@ -11,11 +11,14 @@ import { URLExt } from '@jupyterlab/coreutils';
 import { ServerConnection } from '@jupyterlab/services';
 
 import type {
+  OpenCodeAllSessionsResponse,
   OpenCodeEditResponse,
   OpenCodeEvent,
   OpenCodeMessagesResponse,
+  OpenCodeNotebookSessionsResponse,
   OpenCodeProvidersResponse,
-  OpenCodeRequest
+  OpenCodeRequest,
+  OpenCodeSessionOpResponse
 } from '../types';
 
 /**
@@ -215,6 +218,230 @@ export async function callOpenCodeReplyQuestion(
   return JSON.parse(text);
 }
 
+// ---------------------------------------------------------------------------
+// Multi-session management (1 notebook can bind N sessions; one is active)
+// ---------------------------------------------------------------------------
+
+async function _jsonRequest<T>(
+  url: string,
+  init: RequestInit,
+  serverSettings: ServerConnection.ISettings,
+  label: string
+): Promise<T> {
+  let res: Response;
+  try {
+    res = await ServerConnection.makeRequest(url, init, serverSettings);
+  } catch (error) {
+    throw new Error(
+      `network error calling opencode-bridge/${label}: ${(error as Error).message}`
+    );
+  }
+  const text = await res.text();
+  if (!res.ok) {
+    throw new Error(`opencode-bridge/${label} failed: ${res.status} ${text}`);
+  }
+  if (!text) {
+    throw new Error(`empty response from opencode-bridge/${label}`);
+  }
+  try {
+    return JSON.parse(text) as T;
+  } catch {
+    throw new Error(
+      `non-JSON response from opencode-bridge/${label} (status ${res.status})`
+    );
+  }
+}
+
+/** GET /opencode-bridge/sessions/all — every session on OpenCode Serve. */
+export async function callOpenCodeListAllSessions(
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeAllSessionsResponse> {
+  const url = URLExt.join(
+    serverSettings.baseUrl,
+    'opencode-bridge',
+    'sessions',
+    'all'
+  );
+  return _jsonRequest(
+    url,
+    { method: 'GET' },
+    serverSettings,
+    'sessions/all'
+  );
+}
+
+/** GET /opencode-bridge/sessions/notebook?notebook=... — sessions bound
+ *  to this notebook (enriched with metadata, marked which is active). */
+export async function callOpenCodeListNotebookSessions(
+  notebookPath: string,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeNotebookSessionsResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'notebook'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath);
+  return _jsonRequest(url, { method: 'GET' }, serverSettings, 'sessions/notebook');
+}
+
+/** POST /opencode-bridge/sessions/notebook?notebook=...&title=... —
+ *  create a brand-new session on OpenCode, bind it, set as active. */
+export async function callOpenCodeCreateNotebookSession(
+  notebookPath: string,
+  title: string | undefined,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeSessionOpResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'notebook'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath) +
+    (title ? '&title=' + encodeURIComponent(title) : '');
+  return _jsonRequest(
+    url,
+    { method: 'POST', body: JSON.stringify({}), headers: { 'Content-Type': 'application/json' } },
+    serverSettings,
+    'sessions/notebook (POST)'
+  );
+}
+
+/** PUT /opencode-bridge/sessions/notebook?notebook=...&sessionId=... —
+ *  bind an existing sessionId to this notebook (no OpenCode round-trip)
+ *  and set it as active. */
+export async function callOpenCodeBindExistingSession(
+  notebookPath: string,
+  sessionId: string,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeSessionOpResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'notebook'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath) +
+    '&sessionId=' +
+    encodeURIComponent(sessionId);
+  return _jsonRequest(
+    url,
+    { method: 'PUT', body: JSON.stringify({}), headers: { 'Content-Type': 'application/json' } },
+    serverSettings,
+    'sessions/notebook (PUT)'
+  );
+}
+
+/** DELETE /opencode-bridge/sessions/notebook?notebook=...&sessionId=... —
+ *  delete a specific bound session on OpenCode AND remove its binding. */
+export async function callOpenCodeDeleteNotebookSession(
+  notebookPath: string,
+  sessionId: string,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeSessionOpResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'notebook'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath) +
+    '&sessionId=' +
+    encodeURIComponent(sessionId);
+  return _jsonRequest(
+    url,
+    { method: 'DELETE' },
+    serverSettings,
+    'sessions/notebook (DELETE)'
+  );
+}
+
+/** GET /opencode-bridge/sessions/active?notebook=... — get the active
+ *  sessionId (or null). */
+export async function callOpenCodeGetActiveSession(
+  notebookPath: string,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeSessionOpResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'active'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath);
+  return _jsonRequest(url, { method: 'GET' }, serverSettings, 'sessions/active');
+}
+
+/** PUT /opencode-bridge/sessions/active?notebook=...&sessionId=... —
+ *  switch which bound session is active. sessionId MUST already be
+ *  in the bound list.
+ *
+ *  TODO(frontend): unused in v0.1.x — the cell-action's session
+ *  switcher uses PUT /sessions/notebook (which does both bind and set
+ *  active in one call). This is kept for a future "switch between
+ *  already-bound sessions" flow that avoids the bind round-trip.
+ *  Do NOT delete the corresponding server route without also
+ *  removing this client function (or vice versa). */
+export async function callOpenCodeSetActiveSession(
+  notebookPath: string,
+  sessionId: string,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeSessionOpResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'active'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath) +
+    '&sessionId=' +
+    encodeURIComponent(sessionId);
+  return _jsonRequest(
+    url,
+    { method: 'PUT', body: JSON.stringify({}), headers: { 'Content-Type': 'application/json' } },
+    serverSettings,
+    'sessions/active (PUT)'
+  );
+}
+
+/** DELETE /opencode-bridge/sessions/active?notebook=... — unbind the
+ *  active session (next /edit lazy-creates a new one). Does NOT delete
+ *  the session on OpenCode Serve. */
+export async function callOpenCodeUnbindActiveSession(
+  notebookPath: string,
+  serverSettings: ServerConnection.ISettings
+): Promise<OpenCodeSessionOpResponse> {
+  const url =
+    URLExt.join(
+      serverSettings.baseUrl,
+      'opencode-bridge',
+      'sessions',
+      'active'
+    ) +
+    '?notebook=' +
+    encodeURIComponent(notebookPath);
+  return _jsonRequest(
+    url,
+    { method: 'DELETE' },
+    serverSettings,
+    'sessions/active (DELETE)'
+  );
+}
+
 export interface OpenCodeEventHandlers {
   onEvent: (event: OpenCodeEvent) => void;
   onError?: (err: Error) => void;

src/components/opencode_cell_actions.ts

@@ -1,317 +0,0 @@
-/**
- * Per-cell AI action button rendered inside JupyterLab's native Cell toolbar
- * (top-right of the active cell). Clicking it toggles an
- * OpenCodeInlinePrompt panel attached to the cell's DOM.
- *
- * Registered in index.ts via IToolbarWidgetRegistry.addFactory('Cell', ...).
- *
- * v4 message flow (matches demo.html):
- *   1. User clicks 🪄 -> panel appears, shows session history (setMessages)
- *   2. User submits prompt -> callOpenCodeEdit returns immediately with
- *      sessionId
- *   3. We subscribe to GET /opencode-bridge/events?session=<sid> and
- *      forward each event to the prompt's applyEvent() dispatcher
- *   4. On session.idle we close the stream and re-enable the input
- *
- * The frontend does NO semantic processing of the LLM reply. The chosen
- * provider/model comes from the inline picker (no settings-based default).
- */
-import type { CodeCell } from '@jupyterlab/cells';
-import { Notification } from '@jupyterlab/apputils';
-import type { NotebookPanel } from '@jupyterlab/notebook';
-import { ServerConnection } from '@jupyterlab/services';
-import { Widget } from '@lumino/widgets';
-
-import {
-  callOpenCodeEdit,
-  callOpenCodeReplyPermission,
-  callOpenCodeReplyQuestion,
-  callOpenCodeSessionMessages,
-  subscribeOpenCodeEvents,
-  type OpenCodeEventSubscription
-} from '../api/opencode_client';
-import { extractCellContext } from '../context/cell_context';
-import type {
-  CellContext,
-  OpenCodeProvidersResponse
-} from '../types';
-
-import { OpenCodeInlinePrompt } from './opencode_inline_prompt';
-
-// Module-level runtime injection (set by index.ts after activation).
-let _serverSettings: ServerConnection.ISettings | null = null;
-let _providers: OpenCodeProvidersResponse | null = null;
-
-export function setOpenCodeServerSettings(
-  serverSettings: ServerConnection.ISettings
-): void {
-  _serverSettings = serverSettings;
-}
-
-export function setOpenCodeProviders(
-  p: OpenCodeProvidersResponse | null
-): void {
-  _providers = p;
-}
-
-type Status = 'idle' | 'loading';
-
-export class OpenCodeCellActions extends Widget {
-  private _cell: CodeCell;
-  private _context: CellContext | null = null;
-  private _status: Status = 'idle';
-  private _prompt: OpenCodeInlinePrompt | null = null;
-  private _sseSub: OpenCodeEventSubscription | null = null;
-
-  constructor(cell: CodeCell) {
-    super();
-    this._cell = cell;
-    this.addClass('opencode-cell-actions');
-    this._cell.model.contentChanged.connect(this._onModelChange, this);
-    this._cell.model.stateChanged.connect(this._onModelChange, this);
-    this._render();
-    this._onModelChange();
-  }
-
-  dispose(): void {
-    if (this.isDisposed) {
-      return;
-    }
-    this._closeSse();
-    this._cell.model.contentChanged.disconnect(this._onModelChange, this);
-    this._cell.model.stateChanged.disconnect(this._onModelChange, this);
-    this._hidePrompt();
-    super.dispose();
-  }
-
-  private _onModelChange(): void {
-    this._context = extractCellContextFromCell(this._cell);
-    if (this._prompt) {
-      this._prompt.setDisabled(!this._context || this._status === 'loading');
-    } else {
-      this._render();
-    }
-  }
-
-  private _render(): void {
-    const node = this.node;
-    node.textContent = '';
-
-    const baseDisabled = !this._context || this._status === 'loading';
-
-    const btn = document.createElement('button');
-    btn.className = 'opencode-btn opencode-btn-ai';
-    btn.textContent = 'AI';
-    btn.disabled = baseDisabled;
-    btn.title = baseDisabled
-      ? 'OpenCode: 等待 cell 上下文…'
-      : '让 AI 修改这个 cell 的代码';
-    btn.addEventListener('click', () => {
-      this._togglePrompt();
-    });
-    node.appendChild(btn);
-  }
-
-  private _togglePrompt(): void {
-    if (this._prompt) {
-      this._hidePrompt();
-    } else {
-      this._showPrompt();
-    }
-  }
-
-  private _showPrompt(): void {
-    if (this._prompt) {
-      return;
-    }
-    const prompt = new OpenCodeInlinePrompt(this._cell, {
-      disabled: !this._context || this._status === 'loading',
-      providers: _providers,
-      notebookPath: this._context?.notebookPath,
-      onSubmit: (text: string, providerId?: string, modelId?: string) => {
-        void this._onSubmit(text, providerId, modelId);
-      },
-      onCancel: () => {
-        this._hidePrompt();
-      },
-      onPermissionReply: async (permId, response) => {
-        if (!_serverSettings) {
-          return false;
-        }
-        const sessionId = (this._prompt as any)._sessionId as string | null;
-        if (!sessionId) {
-          return false;
-        }
-        try {
-          const r = await callOpenCodeReplyPermission(
-            sessionId,
-            permId,
-            response,
-            _serverSettings
-          );
-          return r.ok;
-        } catch (e) {
-          console.warn('opencode_bridge: permission reply failed', e);
-          return false;
-        }
-      },
-      onQuestionReply: async (qId, answer) => {
-        if (!_serverSettings) {
-          return false;
-        }
-        const sessionId = (this._prompt as any)._sessionId as string | null;
-        if (!sessionId) {
-          return false;
-        }
-        try {
-          const r = await callOpenCodeReplyQuestion(
-            sessionId,
-            qId,
-            answer,
-            _serverSettings
-          );
-          return r.ok;
-        } catch (e) {
-          console.warn('opencode_bridge: question reply failed', e);
-          return false;
-        }
-      },
-      onStreamEnd: () => {
-        // Centralized: the prompt detected "idle" (any shape) and tells
-        // us to close the SSE stream + restore the input. We no longer
-        // parse event types here.
-        this._closeSse();
-      }
-    });
-    Widget.attach(prompt, this._cell.node);
-    this._prompt = prompt;
-
-    // Fetch the current session's static history and render it before
-    // streaming begins. Empty list is a normal no-op.
-    const notebookPath = this._context?.notebookPath;
-    if (notebookPath) {
-      void this._refreshHistory(notebookPath);
-    }
-  }
-
-  private async _refreshHistory(notebookPath: string): Promise<void> {
-    if (!_serverSettings || !this._prompt) {
-      return;
-    }
-    try {
-      const resp = await callOpenCodeSessionMessages(
-        notebookPath,
-        _serverSettings
-      );
-      this._prompt.setMessages(resp.messages);
-    } catch (e) {
-      console.warn('opencode_bridge: failed to fetch session messages', e);
-    }
-  }
-
-  private _hidePrompt(): void {
-    if (this._prompt) {
-      this._prompt.dispose();
-      this._prompt = null;
-    }
-  }
-
-  private async _onSubmit(
-    text: string,
-    providerId?: string,
-    modelId?: string
-  ): Promise<void> {
-    if (!this._context) {
-      return;
-    }
-    if (!_serverSettings) {
-      Notification.error('OpenCode 运行时未初始化');
-      return;
-    }
-
-    const request = {
-      prompt: text,
-      context: this._context,
-      providerId,
-      modelId
-    };
-
-    this._status = 'loading';
-    if (this._prompt) {
-      this._prompt.setDisabled(true);
-      this._prompt.setSessionId(null);
-    }
-
-    let resp;
-    try {
-      resp = await callOpenCodeEdit(request, _serverSettings);
-    } catch (e) {
-      this._status = 'idle';
-      this._prompt?.setDisabled(false);
-      Notification.error(`OpenCode 失败: ${(e as Error).message}`);
-      return;
-    }
-
-    if (!resp.ok) {
-      this._status = 'idle';
-      this._prompt?.setDisabled(false);
-      Notification.error(`OpenCode 错误: ${resp.error}`);
-      return;
-    }
-
-    // Async edit accepted. Bind the prompt to the returned session, clear
-    // the input, then subscribe to the SSE event stream for this session.
-    this._prompt?.setSessionId(resp.sessionId);
-    this._prompt?.clearInput();
-    this._sseSub = subscribeOpenCodeEvents(
-      resp.sessionId,
-      _serverSettings,
-      {
-        onEvent: ev => {
-          this._prompt?.applyEvent(ev);
-          // Stream-end is detected by the prompt and signalled via
-          // onStreamEnd (see _showPrompt); no idle parsing here.
-        },
-        onError: err => {
-          console.warn('opencode_bridge: SSE error', err);
-          // Don't flip status here: the server may just have hiccuped.
-          // session.idle (if it comes through) will re-enable the input.
-        }
-      }
-    );
-  }
-
-  private _closeSse(): void {
-    if (this._sseSub) {
-      this._sseSub.close();
-      this._sseSub = null;
-    }
-    this._status = 'idle';
-    this._prompt?.setDisabled(false);
-  }
-}
-
-/**
- * Resolve a CodeCell's parent NotebookPanel by walking the parent chain,
- * then build the CellContext.
- */
-function extractCellContextFromCell(cell: CodeCell): CellContext | null {
-  let node: Widget | null = cell.parent;
-  let notebookPanel: NotebookPanel | null = null;
-  while (node) {
-    const candidate = node as any;
-    if (
-      candidate.context &&
-      candidate.content &&
-      Array.isArray(candidate.content.widgets)
-    ) {
-      notebookPanel = candidate;
-      break;
-    }
-    node = node.parent;
-  }
-  if (!notebookPanel) {
-    return null;
-  }
-  return extractCellContext(cell, notebookPanel);
-}

src/components/opencode_floating_panel.ts

@@ -0,0 +1,381 @@
+/**
+ * Global floating AI button + panel, mounted on document.body. Replaces
+ * the per-cell toolbar AI button (formerly OpenCodeCellActions). Click
+ * the round bottom-right button to expand the OpenCodeInlinePrompt; click
+ * again to collapse it.
+ *
+ * The panel operates on the JupyterLab shell's currently-active
+ * NotebookPanel — the (notebookPath, activeCell) pair is resolved at
+ * panel-open time from `app.shell.currentWidget`, and re-resolved when
+ * `app.shell.currentChanged` fires while the panel is open.
+ *
+ * All session/SSE/history state that used to live on
+ * OpenCodeCellActions now lives here. The prompt is created lazily on
+ * the first panel open and disposed on close (recreated on every
+ * re-open so the user always sees a fresh history fetch).
+ */
+import { JupyterFrontEnd } from '@jupyterlab/application';
+import { Notification } from '@jupyterlab/apputils';
+import type { CodeCell } from '@jupyterlab/cells';
+import { ServerConnection } from '@jupyterlab/services';
+import { Widget } from '@lumino/widgets';
+
+import {
+  callOpenCodeBindExistingSession,
+  callOpenCodeCreateNotebookSession,
+  callOpenCodeEdit,
+  callOpenCodeListAllSessions,
+  callOpenCodeReplyPermission,
+  callOpenCodeReplyQuestion,
+  callOpenCodeSessionMessages,
+  subscribeOpenCodeEvents,
+  type OpenCodeEventSubscription
+} from '../api/opencode_client';
+import type { OpenCodeProvidersResponse } from '../types';
+
+import { OpenCodeInlinePrompt } from './opencode_inline_prompt';
+
+export interface IOpenCodeFloatingPanelOptions {
+  app: JupyterFrontEnd;
+  serverSettings: ServerConnection.ISettings;
+  providers: OpenCodeProvidersResponse | null;
+}
+
+type Status = 'idle' | 'loading';
+
+export class OpenCodeFloatingPanel extends Widget {
+  private _app: JupyterFrontEnd;
+  private _serverSettings: ServerConnection.ISettings | null;
+  private _providers: OpenCodeProvidersResponse | null;
+  private _button: HTMLButtonElement;
+  private _panelEl: HTMLDivElement;
+  private _prompt: OpenCodeInlinePrompt | null = null;
+  private _sseSub: OpenCodeEventSubscription | null = null;
+  private _notebookPath: string | null = null;
+  private _status: Status = 'idle';
+
+  constructor(options: IOpenCodeFloatingPanelOptions) {
+    super();
+    this._app = options.app;
+    this._serverSettings = options.serverSettings;
+    this._providers = options.providers;
+    this.addClass('opencode-floating-root');
+    this.node.style.position = 'fixed';
+    this.node.style.bottom = '24px';
+    this.node.style.right = '24px';
+    this.node.style.zIndex = '1000';
+
+    this._button = document.createElement('button');
+    this._button.className = 'opencode-floating-button';
+    this._button.textContent = '🪄';
+    this._button.title = 'OpenCode AI';
+    this._button.addEventListener('click', () => this.toggle());
+    this.node.appendChild(this._button);
+
+    this._panelEl = document.createElement('div');
+    this._panelEl.className = 'opencode-floating-panel';
+    this._panelEl.hidden = true;
+    this.node.appendChild(this._panelEl);
+
+    // JupyterFrontEnd.shell is typed as `JupyterShell | null` in some
+    // JupyterLab versions; cast through any to satisfy strict null checks
+    // while keeping the public API simple.
+    (this._app.shell as any).currentChanged.connect(this._onShellChanged, this);
+  }
+
+  dispose(): void {
+    if (this.isDisposed) {
+      return;
+    }
+    (this._app.shell as any).currentChanged.disconnect(
+      this._onShellChanged,
+      this
+    );
+    this._closeSse();
+    this._hidePrompt();
+    super.dispose();
+  }
+
+  /** Update the providers payload after the initial async fetch. */
+  setProviders(p: OpenCodeProvidersResponse | null): void {
+    this._providers = p;
+  }
+
+  /** Toggle the panel open/closed. */
+  toggle(): void {
+    if (this._panelEl.hidden) {
+      this._showPrompt();
+    } else {
+      this._hidePrompt();
+    }
+  }
+
+  private _onShellChanged = (): void => {
+    // The active notebook changed. If the panel is open, refresh the
+    // underlying prompt so the (provider, model) selection, history,
+    // and active-cell context all reflect the new notebook.
+    //
+    // Implemented as an arrow-function class field (not a method) so
+    // `this` is bound regardless of how the signal's slot invokes us.
+    if (!this._panelEl.hidden) {
+      this._hidePrompt();
+      this._showPrompt();
+    }
+  };
+
+  private _resolveNotebookContext(): {
+    notebookPath: string | null;
+    getActiveCell: () => CodeCell | null;
+  } {
+    const widget = this._app.shell.currentWidget as any;
+    const notebookPath =
+      widget && widget.context && typeof widget.context.path === 'string'
+        ? (widget.context.path as string)
+        : null;
+    const getActiveCell = (): CodeCell | null => {
+      const cur = this._app.shell.currentWidget as any;
+      if (!cur || !cur.content) {
+        return null;
+      }
+      const active = cur.content.activeCell;
+      return (active as CodeCell) || null;
+    };
+    return { notebookPath, getActiveCell };
+  }
+
+  private _showPrompt(): void {
+    if (this._prompt) {
+      this._panelEl.hidden = false;
+      return;
+    }
+    const { notebookPath, getActiveCell } = this._resolveNotebookContext();
+    this._notebookPath = notebookPath;
+    const prompt = new OpenCodeInlinePrompt({
+      disabled: !this._notebookPath || this._status === 'loading',
+      providers: this._providers,
+      notebookPath: this._notebookPath ?? undefined,
+      getActiveCell,
+      onSubmit: (text: string, providerId?: string, modelId?: string) => {
+        void this._onSubmit(text, providerId, modelId);
+      },
+      onCancel: () => {
+        this._hidePrompt();
+      },
+      onPermissionReply: async (permId, response) => {
+        if (!this._serverSettings) {
+          return false;
+        }
+        const sessionId = (this._prompt as any)._sessionId as string | null;
+        if (!sessionId) {
+          return false;
+        }
+        try {
+          const r = await callOpenCodeReplyPermission(
+            sessionId,
+            permId,
+            response,
+            this._serverSettings
+          );
+          return r.ok;
+        } catch (e) {
+          console.warn('opencode_bridge: permission reply failed', e);
+          return false;
+        }
+      },
+      onQuestionReply: async (qId, answer) => {
+        if (!this._serverSettings) {
+          return false;
+        }
+        const sessionId = (this._prompt as any)._sessionId as string | null;
+        if (!sessionId) {
+          return false;
+        }
+        try {
+          const r = await callOpenCodeReplyQuestion(
+            sessionId,
+            qId,
+            answer,
+            this._serverSettings
+          );
+          return r.ok;
+        } catch (e) {
+          console.warn('opencode_bridge: question reply failed', e);
+          return false;
+        }
+      },
+      onStreamEnd: () => {
+        // Centralized: the prompt detected "idle" and signals us to
+        // close the SSE stream + restore the input.
+        this._closeSse();
+      },
+      onListSessions: async () => {
+        if (!this._serverSettings) {
+          return [];
+        }
+        try {
+          const r = await callOpenCodeListAllSessions(this._serverSettings);
+          return r.sessions || [];
+        } catch (e) {
+          console.warn('opencode_bridge: list all sessions failed', e);
+          return [];
+        }
+      },
+      onCreateSession: async () => {
+        if (!this._serverSettings || !this._notebookPath) {
+          throw new Error('notebook not ready');
+        }
+        this._closeSse();
+        const r = await callOpenCodeCreateNotebookSession(
+          this._notebookPath,
+          undefined,
+          this._serverSettings
+        );
+        if (!r.ok || !r.sessionId) {
+          throw new Error(r.error || 'create_session failed');
+        }
+        return r.sessionId;
+      },
+      onSwitchSession: async (sessionId: string) => {
+        if (!this._serverSettings || !this._notebookPath) {
+          return false;
+        }
+        this._closeSse();
+        // PUT /sessions/notebook binds AND sets active in one call.
+        const r = await callOpenCodeBindExistingSession(
+          this._notebookPath,
+          sessionId,
+          this._serverSettings
+        );
+        return !!r.ok;
+      },
+      onReloadHistory: async () => {
+        if (!this._notebookPath) {
+          return;
+        }
+        await this._refreshHistory(this._notebookPath);
+      }
+    });
+    // Use Widget.attach (not raw appendChild) so Lumino sends the
+    // before-attach / after-attach messages — the prompt relies on
+    // these for isAttached/isVisible tracking. The defensive DOM
+    // cleanup in _hidePrompt handles the case where dispose() leaves
+    // a residual node behind (the panel host is an HTMLElement, not a
+    // Widget, so the Lumino parent stays null and dispose() can't
+    // always clean up the DOM on its own).
+    Widget.attach(prompt, this._panelEl);
+    this._prompt = prompt;
+
+    // Load the current session's static history before streaming starts.
+    if (this._notebookPath) {
+      void this._refreshHistory(this._notebookPath);
+    }
+    prompt.initialize();
+    this._panelEl.hidden = false;
+  }
+
+  private async _refreshHistory(notebookPath: string): Promise<void> {
+    if (!this._serverSettings || !this._prompt) {
+      return;
+    }
+    try {
+      const resp = await callOpenCodeSessionMessages(
+        notebookPath,
+        this._serverSettings
+      );
+      this._prompt.setMessages(resp.messages);
+    } catch (e) {
+      console.warn('opencode_bridge: failed to fetch session messages', e);
+    }
+  }
+
+  private _hidePrompt(): void {
+    this._closeSse();
+    if (this._prompt) {
+      const node = this._prompt.node;
+      this._prompt.dispose();
+      // Defensive DOM cleanup: the prompt is attached via raw DOM
+      // (appendChild/Widget.attach with an HTMLElement host), so its
+      // Lumino parent is null. In some scenarios — for example when
+      // the dispose path runs synchronously while another show+hide
+      // cycle is already in flight — the dispose() call does not
+      // remove the node from this._panelEl, leaving a residual node
+      // that the next _showPrompt appends to. Without this defensive
+      // removeChild, the user would see the panel content multiply
+      // with every click.
+      if (node.parentNode === this._panelEl) {
+        this._panelEl.removeChild(node);
+      }
+      this._prompt = null;
+    }
+    this._panelEl.hidden = true;
+  }
+
+  private async _onSubmit(
+    text: string,
+    providerId?: string,
+    modelId?: string
+  ): Promise<void> {
+    if (!this._notebookPath) {
+      Notification.info('请先打开一个 notebook');
+      return;
+    }
+    if (!this._serverSettings) {
+      Notification.error('OpenCode 运行时未初始化');
+      return;
+    }
+
+    const request = {
+      prompt: text,
+      context: { notebookPath: this._notebookPath },
+      providerId,
+      modelId
+    };
+
+    this._status = 'loading';
+    if (this._prompt) {
+      this._prompt.setDisabled(true);
+      this._prompt.setSessionId(null);
+    }
+
+    let resp;
+    try {
+      resp = await callOpenCodeEdit(request, this._serverSettings);
+    } catch (e) {
+      this._status = 'idle';
+      this._prompt?.setDisabled(false);
+      Notification.error(`OpenCode 失败: ${(e as Error).message}`);
+      return;
+    }
+
+    if (!resp.ok) {
+      this._status = 'idle';
+      this._prompt?.setDisabled(false);
+      Notification.error(`OpenCode 错误: ${resp.error}`);
+      return;
+    }
+
+    this._prompt?.setSessionId(resp.sessionId);
+    this._prompt?.clearInput();
+    this._sseSub = subscribeOpenCodeEvents(
+      resp.sessionId,
+      this._serverSettings,
+      {
+        onEvent: ev => {
+          this._prompt?.applyEvent(ev);
+        },
+        onError: err => {
+          console.warn('opencode_bridge: SSE error', err);
+        }
+      }
+    );
+  }
+
+  private _closeSse(): void {
+    if (this._sseSub) {
+      this._sseSub.close();
+      this._sseSub = null;
+    }
+    this._status = 'idle';
+    this._prompt?.setDisabled(false);
+  }
+}

src/components/opencode_inline_prompt.ts

@@ -20,7 +20,7 @@
  * history area. The user can still Copy / Insert / Replace individual
  * code blocks from a finished assistant message.
  */
-import { CodeCell } from '@jupyterlab/cells';
+import type { CodeCell } from '@jupyterlab/cells';
 import { Notification } from '@jupyterlab/apputils';
 import { Widget } from '@lumino/widgets';
 import { marked } from 'marked';
@@ -28,12 +28,10 @@ import { marked } from 'marked';
 import type {
   OpenCodeEvent,
   OpenCodeMessage,
-  OpenCodeProvidersResponse
+  OpenCodeProvidersResponse,
+  OpenCodeSessionMeta
 } from '../types';
-import {
+import { loadModelSelection, saveModelSelection } from './model_selection';
-  loadModelSelection,
-  saveModelSelection
-} from './model_selection';
 
 export interface IOpenCodeInlinePromptOptions {
   onSubmit: (text: string, providerId?: string, modelId?: string) => void;
@@ -47,6 +45,16 @@ export interface IOpenCodeInlinePromptOptions {
    * to the default selection (first provider / `default[pid]` model).
    */
   notebookPath?: string;
+  /**
+   * Return the currently active CodeCell, used by the cell-edit actions
+   * ("📋 插入单元格内容" / "插入到光标" / "替换单元格"). When the host is
+   * decoupled from a specific cell (e.g. a global floating panel that
+   * targets whatever cell the user last focused), it passes a lambda
+   * that resolves the active cell from the JupyterLab shell at click
+   * time. Returns null if no cell is currently selectable — the prompt
+   * then surfaces a "请先选中一个 cell" notification instead of acting.
+   */
+  getActiveCell?: () => CodeCell | null;
   /**
    * Respond to a `permission.asked` event. Returns a promise that resolves
    * to true on success, false on failure (the prompt updates the UI in
@@ -65,6 +73,19 @@ export interface IOpenCodeInlinePromptOptions {
    * the prompt keeps the cell action from re-parsing event types.
    */
   onStreamEnd?: () => void;
+  // ----- session management (multi-session UI) -----
+  /** List ALL OpenCode sessions (for the session-picker dropdown).
+   *  Returns the raw array; the prompt picks the active one out. */
+  onListSessions?: () => Promise<OpenCodeSessionMeta[]>;
+  /** Create a brand-new session, bind it to the current notebook, and
+   *  return its id (which becomes the new active session). */
+  onCreateSession?: () => Promise<string>;
+  /** Switch the active session. Returns true on success. */
+  onSwitchSession?: (sessionId: string) => Promise<boolean>;
+  /** Reload the message history for the currently-active session.
+   *  Called after a create / switch so the panel reflects the new
+   *  conversation's scrollback. */
+  onReloadHistory?: () => Promise<void>;
 }
 
 interface FlatProvider {
@@ -73,12 +94,16 @@ interface FlatProvider {
   models: { [modelID: string]: unknown };
 }
 
-function flattenProviders(
+function flattenProviders(providers: OpenCodeProvidersResponse | null): {
-  providers: OpenCodeProvidersResponse | null
+  providers: FlatProvider[];
-): { providers: FlatProvider[]; defaultMap: { [pid: string]: string } } {
+  defaultMap: { [pid: string]: string };
+} {
   const out: FlatProvider[] = [];
   if (!providers || !providers.providers) {
-    return { providers: out, defaultMap: (providers && providers.default) || {} };
+    return {
+      providers: out,
+      defaultMap: (providers && providers.default) || {}
+    };
   }
   for (const p of providers.providers) {
     if (!p.models || typeof p.models !== 'object') {
@@ -103,7 +128,10 @@ function pickDefaultModelId(
     return undefined;
   }
   const fromDefault = defaultMap[providerId];
-  if (fromDefault && Object.prototype.hasOwnProperty.call(models, fromDefault)) {
+  if (
+    fromDefault &&
+    Object.prototype.hasOwnProperty.call(models, fromDefault)
+  ) {
     return fromDefault;
   }
   return keys[0];
@@ -115,11 +143,11 @@ interface BlockEntry {
 }
 
 export class OpenCodeInlinePrompt extends Widget {
-  private _cell: CodeCell;
   private _options: IOpenCodeInlinePromptOptions;
   private _textarea: HTMLTextAreaElement;
   private _sendBtn: HTMLButtonElement;
   private _cancelBtn: HTMLButtonElement;
+  private _insertCellBtn: HTMLButtonElement;
   private _providerSelect: HTMLSelectElement | null = null;
   private _modelSelect: HTMLSelectElement | null = null;
   private _providerModels: FlatProvider[];
@@ -129,6 +157,10 @@ export class OpenCodeInlinePrompt extends Widget {
   // Streaming state. _sessionId is set by the cell action after a successful
   // /edit response; applyEvent() drops events that don't belong to it.
   private _sessionId: string | null = null;
+  // Multi-session UI: the dropdown and its row (null when the host
+  // did not wire up the session callbacks).
+  private _sessionRow: HTMLDivElement | null = null;
+  private _sessionSelect: HTMLSelectElement | null = null;
   // The current assistant message DOM node (re-rendered as markdown on
   // every text delta so the user sees a properly formatted response in
   // real-time, not raw ```fence``` source).
@@ -141,12 +173,8 @@ export class OpenCodeInlinePrompt extends Widget {
   // Active collapsible blocks (reasoning / tool / etc.), keyed by type.
   private _activeBlocks: { [key: string]: BlockEntry } = {};
 
-  constructor(
+  constructor(options: IOpenCodeInlinePromptOptions) {
-    cell: CodeCell,
-    options: IOpenCodeInlinePromptOptions
-  ) {
     super();
-    this._cell = cell;
     this._options = options;
     this.addClass('opencode-inline-prompt');
 
@@ -206,7 +234,7 @@ export class OpenCodeInlinePrompt extends Widget {
       const modelId = this._modelSelect?.value || undefined;
       options.onSubmit(text, providerId, modelId);
     });
-    this._textarea.addEventListener('keydown', (e) => {
+    this._textarea.addEventListener('keydown', e => {
       if (e.key === 'Enter' && !e.shiftKey && !e.ctrlKey) {
         e.preventDefault();
         this._sendBtn.click();
@@ -219,11 +247,86 @@ export class OpenCodeInlinePrompt extends Widget {
       options.onCancel();
     });
 
+    // "📋 插入单元格内容" button: appends the current cell's source
+    // (wrapped in a markdown code fence) to the textarea. Lets the
+    // user explicitly opt-in to including the cell content in the
+    // LLM prompt — the cell is no longer auto-injected.
+    this._insertCellBtn = document.createElement('button');
+    this._insertCellBtn.type = 'button';
+    this._insertCellBtn.className = 'opencode-btn-insert-cell';
+    this._insertCellBtn.textContent = '📋 插入单元格内容';
+    this._insertCellBtn.title =
+      '把当前 cell 的源码作为 markdown code block 追加到输入框末尾';
+    this._insertCellBtn.addEventListener('click', () => {
+      this._insertCellSource();
+    });
+
     const actions = document.createElement('div');
     actions.className = 'opencode-inline-actions';
+    actions.appendChild(this._insertCellBtn);
     actions.appendChild(this._sendBtn);
     actions.appendChild(this._cancelBtn);
 
+    // Session selector (top of the panel, above provider/model).
+    // Only rendered when the host has provided the multi-session
+    // callbacks. The active session id is the option currently
+    // selected; switching the dropdown calls onSwitchSession, picking
+    // "+ 新建会话" calls onCreateSession, and the refresh button
+    // re-fetches the global session list.
+    if (
+      this._options.onListSessions &&
+      this._options.onCreateSession &&
+      this._options.onSwitchSession
+    ) {
+      this._sessionRow = document.createElement('div');
+      this._sessionRow.className = 'opencode-prompt-sessions';
+
+      const sLabel = document.createElement('label');
+      const sSpan = document.createElement('span');
+      sSpan.textContent = 'Session:';
+      sLabel.appendChild(sSpan);
+
+      this._sessionSelect = document.createElement('select');
+      this._sessionSelect.className = 'opencode-session-select';
+      // Single placeholder until the list loads.
+      this._sessionSelect.appendChild(
+        this._mkSessionOption('', '加载中…', false)
+      );
+      this._sessionSelect.disabled = true;
+      this._sessionSelect.addEventListener('change', () => {
+        const v = this._sessionSelect!.value;
+        if (v === '__new__') {
+          void this._handleCreateSession();
+        } else if (v && v !== this._sessionId) {
+          void this._handleSwitchSession(v);
+        }
+      });
+      sLabel.appendChild(this._sessionSelect);
+      this._sessionRow.appendChild(sLabel);
+
+      const newBtn = document.createElement('button');
+      newBtn.type = 'button';
+      newBtn.className = 'opencode-session-btn-new';
+      newBtn.textContent = '+ 新建';
+      newBtn.title = '在 OpenCode 上创建新会话并绑定到当前 notebook';
+      newBtn.addEventListener('click', () => {
+        void this._handleCreateSession();
+      });
+      this._sessionRow.appendChild(newBtn);
+
+      const refreshBtn = document.createElement('button');
+      refreshBtn.type = 'button';
+      refreshBtn.className = 'opencode-session-btn-refresh';
+      refreshBtn.textContent = '🔄';
+      refreshBtn.title = '刷新 OpenCode 全局会话列表';
+      refreshBtn.addEventListener('click', () => {
+        void this._refreshSessionList();
+      });
+      this._sessionRow.appendChild(refreshBtn);
+
+      this.node.appendChild(this._sessionRow);
+    }
+
     if (this._providerSelect || this._modelSelect) {
       const row = document.createElement('div');
       row.className = 'opencode-prompt-providers';
@@ -254,6 +357,15 @@ export class OpenCodeInlinePrompt extends Widget {
 
     this.node.appendChild(this._textarea);
     this.node.appendChild(actions);
+
+    // Apply the initial disabled state to ALL interactive elements
+    // (provider/model selects, send button, AND the insert-cell
+    // button — the last one depends on `getActiveCell()` which only
+    // resolves correctly here in the constructor). Without this, the
+    // insert button would stay enabled until the first external
+    // setDisabled() call, which is too late for the user's first
+    // click.
+    this.setDisabled(options.disabled);
   }
 
   private _rebuildModelSelect(
@@ -330,6 +442,156 @@ export class OpenCodeInlinePrompt extends Widget {
     return sel;
   }
 
+  // ---------- session selector (multi-session UI) ----------
+
+  /**
+   * Repopulate the session dropdown with the given list. The currently
+   * active session (this._sessionId, set by setSessionId or by
+   * _handleSwitchSession) is marked selected.
+   */
+  private _populateSessionSelect(sessions: OpenCodeSessionMeta[]): void {
+    if (!this._sessionSelect) {
+      return;
+    }
+    // Clear existing options (drop the loading placeholder).
+    while (this._sessionSelect.firstChild) {
+      this._sessionSelect.removeChild(this._sessionSelect.firstChild);
+    }
+    for (const s of sessions) {
+      const label = s.title
+        ? `${s.title} (${s.id.slice(0, 8)}…)`
+        : `${s.id.slice(0, 8)}…`;
+      this._sessionSelect.appendChild(
+        this._mkSessionOption(s.id, label, s.id === this._sessionId)
+      );
+    }
+    // Always-available "create new" sentinel.
+    this._sessionSelect.appendChild(
+      this._mkSessionOption('__new__', '+ 新建会话…', false)
+    );
+    // Reflect the current active id (or "" if none).
+    this._sessionSelect.value = this._sessionId || '';
+    if (!this._sessionId) {
+      // No active session; show a hint via the first option being empty.
+      this._sessionSelect.value = '';
+    }
+    this._sessionSelect.disabled = false;
+  }
+
+  private _mkSessionOption(
+    value: string,
+    label: string,
+    selected: boolean
+  ): HTMLOptionElement {
+    const o = document.createElement('option');
+    o.value = value;
+    o.textContent = label;
+    if (selected) {
+      o.selected = true;
+    }
+    return o;
+  }
+
+  /**
+   * Fetch the global session list from the host and repopulate the
+   * dropdown. Called on prompt show, on "刷新" click, and after
+   * every create / switch. Errors are non-fatal — the dropdown just
+   * keeps whatever it had (or stays empty).
+   */
+  async _refreshSessionList(): Promise<void> {
+    if (!this._options.onListSessions) {
+      return;
+    }
+    try {
+      const sessions = await this._options.onListSessions();
+      this._populateSessionSelect(sessions);
+    } catch (e) {
+      console.warn('opencode_bridge: failed to list sessions', e);
+    }
+  }
+
+  /**
+   * "新建" button or dropdown's __new__ entry. Creates a session,
+   * binds it, sets as active, refreshes the dropdown, and reloads the
+   * message history for the new (empty) session.
+   */
+  private async _handleCreateSession(): Promise<void> {
+    if (!this._options.onCreateSession) {
+      return;
+    }
+    if (this._sessionSelect) {
+      this._sessionSelect.disabled = true;
+    }
+    try {
+      const newId = await this._options.onCreateSession();
+      // setSessionId() handles _sessionId + dropdown + reset pointers
+      // in one call; avoids duplicate work in this handler.
+      this.setSessionId(newId);
+      this._historyEl.textContent = '';
+      // Re-fetch the global list so the new id is in the dropdown
+      // and marked active.
+      await this._refreshSessionList();
+      // Reload history for the new session (empty list, but this
+      // also re-syncs the prompt's view of "current state").
+      if (this._options.onReloadHistory) {
+        try {
+          await this._options.onReloadHistory();
+        } catch (e) {
+          console.warn('opencode_bridge: reload history failed', e);
+        }
+      }
+    } catch (e) {
+      Notification.error('创建会话失败: ' + (e as Error).message);
+      if (this._sessionSelect) {
+        this._sessionSelect.disabled = false;
+      }
+    }
+  }
+
+  /**
+   * User picked a different session from the dropdown. Asks the host
+   * to bind + set active; on success, refreshes history.
+   */
+  private async _handleSwitchSession(sessionId: string): Promise<void> {
+    if (!this._options.onSwitchSession) {
+      return;
+    }
+    if (this._sessionSelect) {
+      this._sessionSelect.disabled = true;
+    }
+    try {
+      const ok = await this._options.onSwitchSession(sessionId);
+      if (ok) {
+        // setSessionId() handles _sessionId + dropdown + reset
+        // pointers in one call; avoids duplicate work.
+        this.setSessionId(sessionId);
+        this._historyEl.textContent = '';
+        if (this._options.onReloadHistory) {
+          try {
+            await this._options.onReloadHistory();
+          } catch (e) {
+            console.warn('opencode_bridge: reload history failed', e);
+          }
+        }
+      } else {
+        // Roll back the select to the previous value.
+        if (this._sessionSelect) {
+          this._sessionSelect.value = this._sessionId || '';
+        }
+        Notification.error('切换会话失败');
+      }
+    } catch (e) {
+      Notification.error('切换会话失败: ' + (e as Error).message);
+      if (this._sessionSelect) {
+        this._sessionSelect.value = this._sessionId || '';
+      }
+    } finally {
+      if (this._sessionSelect) {
+        this._sessionSelect.disabled = false;
+      }
+    }
+  }
+
   /**
    * Persist the current (providerSelect.value, modelSelect.value) for
    * this notebook. No-op if the prompt has no notebookPath, no
@@ -356,6 +618,20 @@ export class OpenCodeInlinePrompt extends Widget {
     if (this._modelSelect) {
       this._modelSelect.disabled = disabled;
     }
+    if (this._sessionSelect) {
+      // Don't disable the select while streaming — the user can still
+      // switch to a different session to inspect it. The cell action
+      // closes the SSE on switch.
+      this._sessionSelect.disabled = false;
+    }
+    // The "📋 插入单元格内容" button is only meaningful when there is
+    // an active cell. Reflect availability in its disabled state so
+    // the user can see at a glance whether the action will work, and
+    // the click handler can still no-op gracefully via Notification.
+    if (this._insertCellBtn) {
+      const hasActiveCell = !!this._options.getActiveCell?.();
+      this._insertCellBtn.disabled = disabled || !hasActiveCell;
+    }
   }
 
   /** Clear the user input textarea. */
@@ -363,18 +639,80 @@ export class OpenCodeInlinePrompt extends Widget {
     this._textarea.value = '';
   }
 
+  /**
+   * "📋 插入单元格内容" button: append the current cell's source as a
+   * markdown code block to the textarea. The LLM only sees what the
+   * user explicitly chose to include — the cell source is NEVER
+   * auto-injected (v0.2.x change).
+   *
+   * The cell is resolved at click time through the host-provided
+   * `getActiveCell` callback, so the prompt itself stays decoupled
+   * from any specific CodeCell instance.
+   */
+  private _insertCellSource(): void {
+    const cell = this._options.getActiveCell?.() ?? null;
+    if (!cell || !cell.model || !cell.model.sharedModel) {
+      Notification.info('请先选中一个 cell');
+      return;
+    }
+    const source = cell.model.sharedModel.getSource() as string;
+    if (!source || !source.trim()) {
+      Notification.info('当前 cell 为空');
+      return;
+    }
+    // Use the cell's language as the fence info string when it
+    // looks like a real language identifier; otherwise use a plain
+    // fence so markdown stays portable.
+    const langRaw = (cell.model as any).type
+      ? ((cell.model as any).type as string)
+      : 'python';
+    const lang = /^[a-zA-Z0-9_+\-#]+$/.test(langRaw) ? langRaw : '';
+    const block = '\n```' + lang + '\n' + source.replace(/\n$/, '') + '\n```\n';
+    const before = this._textarea.value;
+    const needsLeadingNewline = before.length > 0 && !before.endsWith('\n');
+    const insertion = (needsLeadingNewline ? '\n' : '') + block;
+    this._textarea.value = before + insertion;
+    // Move cursor to end so the user can continue typing.
+    this._textarea.focus();
+    const end = this._textarea.value.length;
+    this._textarea.setSelectionRange(end, end);
+    this._scrollToBottom();
+  }
+
   /**
    * Bind the prompt to a specific OpenCode session id. Events arriving via
    * `applyEvent` for a different session are dropped. Pass null to clear.
    */
   setSessionId(sessionId: string | null): void {
     this._sessionId = sessionId;
+    if (this._sessionSelect) {
+      // Reflect the new active id in the dropdown without rebuilding it.
+      if (sessionId) {
+        const has = Array.from(this._sessionSelect.options).some(
+          o => o.value === sessionId
+        );
+        if (has) {
+          this._sessionSelect.value = sessionId;
+        }
+      } else {
+        this._sessionSelect.value = '';
+      }
+    }
     if (sessionId) {
       // Fresh turn: drop any in-progress stream DOM from a previous session.
       this._resetStreamPointers();
     }
   }
 
+  /**
+   * First-time wiring after the prompt is constructed. Loads the global
+   * session list into the dropdown. Call from the host (cell action)
+   * right after constructing the widget.
+   */
+  initialize(): void {
+    void this._refreshSessionList();
+  }
+
   /**
    * Render the current session's static messages (loaded once from
    * /session-messages when the panel opens). Subsequent assistant turns
@@ -402,9 +740,7 @@ export class OpenCodeInlinePrompt extends Widget {
   applyEvent(event: OpenCodeEvent): void {
     const type = event.type || (event.payload && event.payload.type) || '';
     const props =
-      event.properties ||
+      event.properties || (event.payload && event.payload.properties) || {};
-      (event.payload && event.payload.properties) ||
-      {};
     const sessionID =
       props.sessionID ||
       props.sessionId ||
@@ -413,16 +749,25 @@ export class OpenCodeInlinePrompt extends Widget {
         event.payload.syncEvent &&
         event.payload.syncEvent.aggregateID);
 
-    // Drop events for other sessions (defensive; matches demo.html
+    // System / workspace / pty / etc. events are not displayed.
-    // handleGlobalEvent). Only drop when the event has an explicit
+    if (this._isSystemEvent(type)) {
-    // sessionID — events without one (e.g. system events) are still
-    // processed and may be dropped by _isSystemEvent below.
-    if (sessionID && this._sessionId && sessionID !== this._sessionId) {
       return;
     }
 
-    // System / workspace / pty / etc. events are not displayed.
+    // Cross-session filtering: only strict for permission/question
-    if (this._isSystemEvent(type)) {
+    // events (the user must NOT be able to reply to a permission
+    // prompt that belongs to a different session). Content events
+    // (text delta, reasoning, tool, idle) pass through regardless of
+    // sessionID match — the user is looking at the active session's
+    // panel, and we don't want to drop their reply because of a
+    // sessionID extraction edge case. The server already forwards
+    // ALL events; the SSE handler routes by URL ?session= param.
+    if (
+      (type === 'permission.asked' || type === 'question.asked') &&
+      sessionID &&
+      this._sessionId &&
+      sessionID !== this._sessionId
+    ) {
       return;
     }
 
@@ -444,13 +789,14 @@ export class OpenCodeInlinePrompt extends Widget {
     type: string,
     props: { [k: string]: any }
   ): boolean {
-
     if (type === 'permission.asked') {
       const permId = String(props.id || props.permissionID || '');
       this._createPermissionBlock(
         permId,
         String(
-          props.description || props.title || '系统请求执行权限（命令行/文件修改）'
+          props.description ||
+            props.title ||
+            '系统请求执行权限（命令行/文件修改）'
         )
       );
       return true;
@@ -502,7 +848,11 @@ export class OpenCodeInlinePrompt extends Widget {
       return true;
     }
     if (type === 'session.next.tool.input.delta') {
-      this._appendToBlock('tool', '🛠️ 工具输入与参数', String(props.delta || ''));
+      this._appendToBlock(
+        'tool',
+        '🛠️ 工具输入与参数',
+        String(props.delta || '')
+      );
       return true;
     }
     if (type === 'session.next.tool.progress') {
@@ -564,10 +914,7 @@ export class OpenCodeInlinePrompt extends Widget {
     }
     const payload = event.payload;
     if (payload) {
-      return check(
+      return check(payload.type || topType, payload.properties || topProps);
-        payload.type || topType,
-        payload.properties || topProps
-      );
     }
     return false;
   }
@@ -653,8 +1000,7 @@ export class OpenCodeInlinePrompt extends Widget {
     }
     const details = document.createElement('details');
     details.id = domId;
-    details.className =
+    details.className = 'opencode-msg-block opencode-msg-block-interaction';
-      'opencode-msg-block opencode-msg-block-interaction';
     details.open = true;
     const summary = document.createElement('summary');
     summary.textContent = '🔐 权限请求等待处理';
@@ -736,8 +1082,7 @@ export class OpenCodeInlinePrompt extends Widget {
     }
     const details = document.createElement('details');
     details.id = domId;
-    details.className =
+    details.className = 'opencode-msg-block opencode-msg-block-interaction';
-      'opencode-msg-block opencode-msg-block-interaction';
     details.open = true;
     const summary = document.createElement('summary');
     summary.textContent = '❓ Agent 提问等待回复';
@@ -760,14 +1105,9 @@ export class OpenCodeInlinePrompt extends Widget {
     submit.className = 'opencode-q-submit';
     submit.textContent = '提交回答';
     submit.addEventListener('click', () => {
-      void this._handleQuestionResponse(
+      void this._handleQuestionResponse(questionId, input, inputRow, details);
-        questionId,
-        input,
-        inputRow,
-        details
-      );
     });
-    input.addEventListener('keydown', (e) => {
+    input.addEventListener('keydown', e => {
       if (e.key === 'Enter') {
         e.preventDefault();
         submit.click();
@@ -795,7 +1135,8 @@ export class OpenCodeInlinePrompt extends Widget {
       return;
     }
     if (!this._options.onQuestionReply) {
-      inputRow.innerHTML = '<span style="color: #64748b;">(未配置 onQuestionReply 回调)</span>';
+      inputRow.innerHTML =
+        '<span style="color: #64748b;">(未配置 onQuestionReply 回调)</span>';
       return;
     }
     inputRow.innerHTML = '<span style="color: #64748b;">正在提交…</span>';
@@ -925,8 +1266,9 @@ export class OpenCodeInlinePrompt extends Widget {
   }
 
   private _insertAtCursor(text: string): void {
-    const cell = this._cell;
+    const cell = this._options.getActiveCell?.() ?? null;
     if (!cell || !cell.model || !cell.model.sharedModel) {
+      Notification.info('请先选中一个 cell');
       return;
     }
     const sharedModel = cell.model.sharedModel;
@@ -934,9 +1276,8 @@ export class OpenCodeInlinePrompt extends Widget {
     let offset = source.length;
     try {
       const editor = (cell as any).editor;
-      const pos = editor && editor.getCursorPosition
+      const pos =
-        ? editor.getCursorPosition()
+        editor && editor.getCursorPosition ? editor.getCursorPosition() : null;
-        : null;
       if (pos) {
         const lines = source.split('\n');
         const line = Math.max(0, Math.min(pos.line, lines.length - 1));
@@ -959,8 +1300,9 @@ export class OpenCodeInlinePrompt extends Widget {
   }
 
   private _replaceCell(text: string): void {
-    const cell = this._cell;
+    const cell = this._options.getActiveCell?.() ?? null;
     if (!cell || !cell.model || !cell.model.sharedModel) {
+      Notification.info('请先选中一个 cell');
       return;
     }
     cell.model.sharedModel.setSource(text);

src/context/cell_context.ts

@@ -1,81 +0,0 @@
-/**
- * Extract a CellContext snapshot from a CodeCell + its parent NotebookPanel.
- *
- * Pure functions, no DOM, no signals — testable with plain object mocks.
- */
-import type { CodeCell, ICodeCellModel } from '@jupyterlab/cells';
-import type { NotebookPanel } from '@jupyterlab/notebook';
-
-import type { CellContext, ErrorOutput } from '../types';
-
-/**
- * Find the first error output in a code cell's outputs.
- * Returns null if the cell has no error output or is not a code cell.
- */
-export function collectErrorOutputs(model: ICodeCellModel): ErrorOutput | null {
-  const outputs = model.outputs;
-  for (let i = 0; i < outputs.length; i++) {
-    const out = outputs.get(i);
-    if (out && out.type === 'error') {
-      const e = out as {
-        ename?: unknown;
-        evalue?: unknown;
-        traceback?: unknown;
-      };
-      return {
-        ename: String(e.ename ?? ''),
-        evalue: String(e.evalue ?? ''),
-        traceback: Array.isArray(e.traceback) ? (e.traceback as string[]) : [],
-      };
-    }
-  }
-  return null;
-}
-
-/**
- * Build a CellContext from a CodeCell and its parent NotebookPanel.
- * Returns null if essential data is missing.
- *
- * @param cell The code cell to inspect.
- * @param panel The notebook panel that contains the cell.
- */
-export function extractCellContext(
-  cell: CodeCell,
-  panel: NotebookPanel
-): CellContext | null {
-  if (!cell || !panel) {
-    return null;
-  }
-
-  const cells = panel.content.widgets;
-  const cellIndex = cells ? cells.indexOf(cell) : -1;
-  if (cellIndex < 0) {
-    return null;
-  }
-
-  const totalCells = cells ? cells.length : 0;
-  const previousCell = cellIndex > 0 ? cells[cellIndex - 1] : null;
-  const previousCode = previousCell
-    ? previousCell.model.sharedModel.getSource()
-    : null;
-
-  // Language: use 'python' as default for code cells.
-  // Future improvement: read from kernel info_reply.
-  const language = 'python';
-
-  let error: ErrorOutput | null = null;
-  if (cell.model.type === 'code') {
-    error = collectErrorOutputs(cell.model as ICodeCellModel);
-  }
-
-  return {
-    notebookPath: panel.context.path,
-    cellId: cell.model.id,
-    language,
-    cellIndex,
-    totalCells,
-    source: cell.model.sharedModel.getSource(),
-    previousCode,
-    error,
-  };
-}

src/index.ts

@@ -3,74 +3,56 @@ import {
   JupyterFrontEndPlugin
 } from '@jupyterlab/application';
 
-import { IToolbarWidgetRegistry } from '@jupyterlab/apputils';
-import { Cell, CodeCell } from '@jupyterlab/cells';
 import { Widget } from '@lumino/widgets';
 
-import {
+import { OpenCodeFloatingPanel } from './components/opencode_floating_panel';
-  OpenCodeCellActions,
-  setOpenCodeProviders,
-  setOpenCodeServerSettings
-} from './components/opencode_cell_actions';
 import { requestAPI } from './request';
 import { callOpenCodeProviders } from './api/opencode_client';
 
 /**
  * Initialization data for the opencode_bridge extension.
  *
- * v3-final: no JupyterLab plugin settings. Connection config is read from
+ * v5-floating: the per-cell AI button is gone. A single
- * environment variables by the server extension; the model is picked
+ * OpenCodeFloatingPanel is attached to document.body and operates
- * dynamically in the inline prompt.
+ * against the JupyterLab shell's currently-active notebook. The model
+ * is picked dynamically in the inline prompt.
  */
 const plugin: JupyterFrontEndPlugin<void> = {
   id: 'opencode_bridge:plugin',
   description: 'A JupyterLab extension bridging the UI to OpenCode Serve.',
   autoStart: true,
-  optional: [IToolbarWidgetRegistry],
+  activate: (app: JupyterFrontEnd) => {
-  activate: (
-    app: JupyterFrontEnd,
-    toolbarRegistry: IToolbarWidgetRegistry | null
-  ) => {
     console.log('JupyterLab extension opencode_bridge is activated!');
 
-    // Push the Jupyter server settings into the actions module so that
+    // Mount the floating AI button on the body. The panel itself is
-    // callOpenCodeEdit can build the right base URL.
+    // hidden until the user clicks the button.
-    setOpenCodeServerSettings(app.serviceManager.serverSettings);
+    const floating = new OpenCodeFloatingPanel({
+      app,
+      serverSettings: app.serviceManager.serverSettings,
+      providers: null
+    });
+    Widget.attach(floating, document.body);
 
-    // Register the per-cell AI actions into the native Cell toolbar
+    // Fetch available providers once at activation and cache them for
-    // (top-right of the active cell, next to move up/down). Non-code
+    // the inline prompt's model picker. Failure is non-fatal (the
-    // cells get an empty widget so they show no AI buttons.
+    // picker hides). Also push the payload into the floating panel so
-    if (toolbarRegistry) {
+    // the prompt can render selects without an extra round trip.
-      toolbarRegistry.addFactory<Cell>(
-        'Cell',
-        'opencode-cell-actions',
-        (cell: Cell) => {
-          if (cell instanceof CodeCell) {
-            return new OpenCodeCellActions(cell);
-          }
-          return new Widget();
-        }
-      );
-    }
-
-    // Fetch available providers once at activation and cache them for the
-    // inline prompt's model picker. Failure is non-fatal (the picker hides).
     void callOpenCodeProviders(app.serviceManager.serverSettings)
       .then(data => {
-        setOpenCodeProviders(data);
+        floating.setProviders(data);
         const lines: string[] = [
           '[opencode_bridge] Available OpenCode providers:'
         ];
         for (const p of data.providers) {
-          const models = Object.values(p.models).map(m => m.id).join(', ');
+          const models = Object.values(p.models)
+            .map(m => m.id)
+            .join(', ');
           lines.push(`  - ${p.id}: ${models || '(no models)'}`);
         }
-        // eslint-disable-next-line no-console
         console.log(lines.join('\n'));
       })
       .catch(reason => {
-        // eslint-disable-next-line no-console
+        console.warn(
-+        console.warn(
           '[opencode_bridge] Could not fetch providers (is the opencode-bridge server extension enabled and opencode serve running?):',
           reason
         );

src/types.ts

@@ -10,21 +10,19 @@
  * a JSON object with a `type` string; consumers route on `type`.
  */
 
-export interface ErrorOutput {
+/**
-  ename: string;
+ * Minimal context carried with each edit request. Only the
-  evalue: string;
+ * notebookPath is needed (so the server can pick the right OpenCode
-  traceback: string[];
+ * session). The cell source, previous-cell, and traceback are NO
-}
+ * LONGER auto-injected into the LLM prompt — the user inserts them
-
+ * manually via the "📋 插入单元格内容" button (or pastes anything
+ * else they want) so the LLM only sees what they explicitly chose
+ * to send. v0.1.x used to pack a lot more here; that auto-wrap
+ * made the LLM context hard to reason about and made the user's
+ * intent ambiguous.
+ */
 export interface CellContext {
   notebookPath: string;
-  cellId: string;
-  language: string;
-  cellIndex: number;
-  totalCells: number;
-  source: string;
-  previousCode: string | null;
-  error: ErrorOutput | null;
 }
 
 export interface OpenCodeRequest {
@@ -82,6 +80,54 @@ export interface OpenCodeMessagesResponse {
   messages: OpenCodeMessage[];
 }
 
+// ---------------------------------------------------------------------------
+// Multi-session management types (1 notebook can bind N sessions, one active)
+// ---------------------------------------------------------------------------
+
+/** One session on the OpenCode Serve side (returned by GET /session). */
+export interface OpenCodeSessionMeta {
+  id: string;
+  title?: string;
+  createdAt?: number;
+  updatedAt?: number;
+  [k: string]: unknown;
+}
+
+/** Response from GET /opencode-bridge/sessions/all. */
+export interface OpenCodeAllSessionsResponse {
+  ok: boolean;
+  sessions: OpenCodeSessionMeta[];
+  error?: string;
+}
+
+/** One session bound to a notebook (returned by GET /sessions/notebook). */
+export interface OpenCodeNotebookSession {
+  sessionId: string;
+  title?: string;
+  createdAt?: number;
+  updatedAt?: number;
+  isActive: boolean;
+}
+
+/** Response from GET /opencode-bridge/sessions/notebook?notebook=... */
+export interface OpenCodeNotebookSessionsResponse {
+  ok: boolean;
+  notebookPath: string;
+  activeSessionId: string | null;
+  sessions: OpenCodeNotebookSession[];
+  error?: string;
+}
+
+/** Response from POST/PUT /sessions/notebook and PUT /sessions/active. */
+export interface OpenCodeSessionOpResponse {
+  ok: boolean;
+  notebookPath: string;
+  sessionId?: string;
+  activeSessionId?: string | null;
+  deleted?: boolean;
+  error?: string;
+}
+
 /** Response from GET /opencode-bridge/providers (proxies OpenCode /config/providers).
  *  Each Provider.models is a Record keyed by modelID (NOT an array). */
 export interface OpenCodeModel {

style/base.css

@@ -4,30 +4,72 @@
     https://jupyterlab.readthedocs.io/en/stable/developer/css.html
 */
 
-/* Single AI action button inside the native Cell toolbar (active cell, top-right). */
+/* Floating AI launcher (replaces the per-cell toolbar button).
-.opencode-cell-actions {
+   Mounted on document.body with position: fixed so it sits above the
+   JupyterLab layout regardless of which dock is active. The panel
+   (when open) renders above the button via column flex. */
+.opencode-floating-root {
+  position: fixed;
+  bottom: 24px;
+  right: 24px;
+  z-index: 1000;  /* above JupyterLab's main UI (z-index tops out around 100) */
   display: flex;
-  align-items: center;
+  flex-direction: column;
+  align-items: flex-end;
+  gap: 8px;
 }
 
-.opencode-cell-actions .opencode-btn {
+.opencode-floating-button {
+  width: 48px;
+  height: 48px;
+  border-radius: 50%;
   border: none;
-  background: transparent;
+  background: var(--jp-brand-color1, #1976d2);
-  padding: 0 6px;
+  color: white;
-  font-size: var(--jp-ui-font-size1);
+  font-size: 20px;
-  line-height: 20px;
   cursor: pointer;
-  white-space: nowrap;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
+  transition: transform 0.15s ease, box-shadow 0.15s ease;
+  padding: 0;
+  line-height: 1;
+}
+.opencode-floating-button:hover {
+  transform: scale(1.05);
+  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.25);
+}
+.opencode-floating-button:focus {
+  outline: 2px solid var(--jp-brand-color2, #42a5f5);
+  outline-offset: 2px;
 }
 
-.opencode-cell-actions .opencode-btn:hover:enabled {
+.opencode-floating-panel {
-  background: var(--jp-layout-color2);
+  width: 480px;
-  border-radius: 2px;
+  max-width: calc(100vw - 48px);
+  max-height: 60vh;
+  overflow: hidden;
+  display: flex;
+  flex-direction: column;
+  background: var(--jp-layout-color1, #fff);
+  border: 1px solid var(--jp-border-color2, #ddd);
+  border-radius: 6px;
+  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.18);
+}
+.opencode-floating-panel[hidden] {
+  display: none;
 }
 
-.opencode-cell-actions .opencode-btn:disabled {
+/* The inline prompt inside the floating panel should fill it: drop
-  opacity: 0.4;
+   the standalone panel's own margin/border, and let the panel's
-  cursor: default;
+   scrollable region take over. */
+.opencode-floating-panel .opencode-inline-prompt {
+  margin: 0;
+  border: none;
+  border-radius: 0;
+  flex: 1;
+  overflow-y: auto;
+}
+.opencode-floating-panel .opencode-inline-history {
+  max-height: 40vh;
 }
 
 /* Inline prompt panel attached to the cell when the AI button is clicked. */
@@ -191,6 +233,7 @@
   display: flex;
   justify-content: flex-end;
   gap: 4px;
+  align-items: center;
 }
 
 .opencode-inline-prompt .opencode-inline-actions button {
@@ -211,6 +254,19 @@
   cursor: default;
 }
 
+/* The "📋 插入单元格内容" button: left-aligned, visually distinct from
+   send/cancel so the user can tell at a glance it's a "modifier"
+   rather than a "submit/cancel" action. */
+.opencode-inline-prompt .opencode-btn-insert-cell {
+  margin-right: auto;  /* push to the left; send/cancel stay on the right */
+  background: #dbeafe;
+  color: #1e40af;
+  border-color: #93c5fd;
+}
+.opencode-inline-prompt .opencode-btn-insert-cell:hover:enabled {
+  background: #bfdbfe;
+}
+
 /* ------------------------------------------------------------------
    Streaming event blocks (v4+ — see opencode_inline_prompt.applyEvent)
    ------------------------------------------------------------------ */
@@ -339,3 +395,52 @@
 .opencode-inline-prompt .opencode-q-submit:hover {
   background: var(--jp-layout-color3, #e0e0e0);
 }
+
+/* ------------------------------------------------------------------
+   Session selector (multi-session UI) — top of the inline prompt
+   ------------------------------------------------------------------ */
+.opencode-inline-prompt .opencode-prompt-sessions {
+  display: flex;
+  gap: 6px;
+  align-items: center;
+  flex-wrap: wrap;
+  margin: 2px 0 4px;
+}
+.opencode-inline-prompt .opencode-prompt-sessions label {
+  display: flex;
+  align-items: center;
+  gap: 4px;
+  font-size: var(--jp-ui-font-size1);
+  color: var(--jp-ui-font-color1, #333);
+  flex: 1;
+  min-width: 0;
+}
+.opencode-inline-prompt .opencode-session-select {
+  flex: 1;
+  min-width: 0;
+  padding: 2px 4px;
+  font-size: var(--jp-ui-font-size1);
+  font-family: inherit;
+  border: 1px solid var(--jp-border-color2, #ccc);
+  border-radius: 3px;
+  background: var(--jp-layout-color1, #fff);
+}
+.opencode-inline-prompt .opencode-session-btn-new,
+.opencode-inline-prompt .opencode-session-btn-refresh {
+  border: 1px solid var(--jp-border-color2, #ccc);
+  background: var(--jp-layout-color2, #f0f0f0);
+  padding: 2px 8px;
+  border-radius: 3px;
+  cursor: pointer;
+  font-size: var(--jp-ui-font-size0, 11px);
+  color: var(--jp-ui-font-color1, #333);
+}
+.opencode-inline-prompt .opencode-session-btn-new:hover,
+.opencode-inline-prompt .opencode-session-btn-refresh:hover {
+  background: var(--jp-layout-color3, #e0e0e0);
+}
+.opencode-inline-prompt .opencode-session-btn-new {
+  background: #dbeafe;
+  color: #1e40af;
+  border-color: #93c5fd;
+}