diff --git a/src/__tests__/opencode_cell_actions.spec.ts b/src/__tests__/opencode_cell_actions.spec.ts
new file mode 100644
index 0000000..0067753
--- /dev/null
+++ b/src/__tests__/opencode_cell_actions.spec.ts
@@ -0,0 +1,161 @@
+/**
+ * Unit tests for OpenCodeCellActions DOM rendering and button disabled states.
+ *
+ * Mocks @jupyterlab/cells, @jupyterlab/apputils, and @lumino/widgets at the
+ * test boundary so the real ESM packages are not loaded (Jest + pnpm can't
+ * transform the hoisted @jupyterlab/* packages out of the box).
+ */
+jest.mock('@jupyterlab/cells', () => ({
+  CodeCell: class CodeCell {}
+}));
+
+jest.mock('@jupyterlab/apputils', () => ({
+  Notification: {
+    info: jest.fn(),
+    error: jest.fn(),
+    success: jest.fn(),
+    warning: jest.fn()
+  }
+}));
+
+jest.mock('@lumino/widgets', () => {
+  class Widget {
+    public node: HTMLElement = document.createElement('div');
+    public id = '';
+    public parent: Widget | null = null;
+    private _isDisposed = false;
+    public get isDisposed(): boolean {
+      return this._isDisposed;
+    }
+    public addClass(cls: string): void {
+      this.node.classList.add(cls);
+    }
+    public dispose(): void {
+      this._isDisposed = true;
+    }
+  }
+  return { Widget };
+});
+
+import { OpenCodeCellActions } from '../components/opencode_cell_actions';
+import { CodeCell } from '@jupyterlab/cells';
+
+function makeFakeOutputs(items: any[]): any {
+  return {
+    get length() {
+      return items.length;
+    },
+    get(i: number) {
+      return items[i];
+    }
+  };
+}
+
+function makeFakeCell(
+  source: string,
+  errorOutputs: any[] = [],
+  notebookPath = 'foo.ipynb',
+  cellIndex = 0,
+  totalCells = 1
+): CodeCell {
+  const model: any = {
+    id: 'cell-test',
+    type: 'code',
+    sharedModel: {
+      getSource: () => source
+    },
+    outputs: makeFakeOutputs(errorOutputs),
+    contentChanged: { connect: jest.fn(), disconnect: jest.fn() },
+    stateChanged: { connect: jest.fn(), disconnect: jest.fn() }
+  };
+  const cell = new (CodeCell as unknown as new () => CodeCell)();
+  (cell as any).model = model;
+
+  // Parent chain: cell -> notebook -> panel (mirrors real JupyterLab, where
+  // the cell's grandparent Notebook matches the duck-typed panel lookup).
+  const notebook: any = { widgets: [] as CodeCell[] };
+  const panel: any = {
+    context: { path: notebookPath },
+    content: notebook
+  };
+  for (let i = 0; i < cellIndex; i++) {
+    notebook.widgets.push({ model: { sharedModel: { getSource: () => '' } } } as any);
+  }
+  notebook.widgets.push(cell);
+  for (let i = cellIndex + 1; i < totalCells; i++) {
+    notebook.widgets.push({ model: { sharedModel: { getSource: () => '' } } } as any);
+  }
+
+  Object.defineProperty(cell, 'parent', { value: notebook, configurable: true });
+  Object.defineProperty(notebook, 'parent', { value: panel, configurable: true });
+
+  return cell as CodeCell;
+}
+
+describe('OpenCodeCellActions', () => {
+  it('renders 3 buttons with the expected labels', () => {
+    const cell = makeFakeCell('x = 1');
+    const actions = new OpenCodeCellActions(cell);
+    const btns = actions.node.querySelectorAll('button');
+    expect(btns.length).toBe(3);
+    expect(btns[0].textContent).toBe('✨ 优化');
+    expect(btns[1].textContent).toBe('🐛 排错');
+    expect(btns[2].textContent).toBe('🪄 编辑');
+  });
+
+  it('disables all buttons when the notebook panel cannot be resolved', () => {
+    const cell = new (CodeCell as unknown as new () => CodeCell)();
+    (cell as any).model = {
+      id: 'orphan',
+      type: 'code',
+      sharedModel: { getSource: () => 'x = 1' },
+      outputs: makeFakeOutputs([]),
+      contentChanged: { connect: jest.fn(), disconnect: jest.fn() },
+      stateChanged: { connect: jest.fn(), disconnect: jest.fn() }
+    };
+    // No parent chain: extractCellContextFromCell must return null.
+    const actions = new OpenCodeCellActions(cell);
+    const btns = actions.node.querySelectorAll('button');
+    btns.forEach((b: HTMLButtonElement) => {
+      expect(b.disabled).toBe(true);
+    });
+  });
+
+  it('enables optimize and edit; fix stays disabled without an error', () => {
+    const cell = makeFakeCell('x = 1', [], 'foo.ipynb', 0, 1);
+    const actions = new OpenCodeCellActions(cell);
+    const btns = actions.node.querySelectorAll('button');
+    expect((btns[0] as HTMLButtonElement).disabled).toBe(false);
+    expect((btns[1] as HTMLButtonElement).disabled).toBe(true);
+    expect((btns[2] as HTMLButtonElement).disabled).toBe(false);
+  });
+
+  it('enables the fix button when the cell has an error output', () => {
+    const cell = makeFakeCell(
+      '1/0',
+      [
+        {
+          type: 'error',
+          ename: 'ZeroDivisionError',
+          evalue: 'div by zero',
+          traceback: []
+        }
+      ],
+      'foo.ipynb',
+      0,
+      1
+    );
+    const actions = new OpenCodeCellActions(cell);
+    const btns = actions.node.querySelectorAll('button');
+    expect((btns[1] as HTMLButtonElement).disabled).toBe(false);
+  });
+
+  it('disconnects model signals on dispose', () => {
+    const cell = makeFakeCell('x = 1');
+    const actions = new OpenCodeCellActions(cell);
+    actions.dispose();
+    const model = (cell as any).model;
+    expect(model.contentChanged.disconnect).toHaveBeenCalled();
+    expect(model.stateChanged.disconnect).toHaveBeenCalled();
+  });
+});
diff --git a/src/components/opencode_cell_actions.ts b/src/components/opencode_cell_actions.ts
new file mode 100644
index 0000000..02b2f5e
--- /dev/null
+++ b/src/components/opencode_cell_actions.ts
@@ -0,0 +1,179 @@
+/**
+ * Per-cell actions widget rendered inside JupyterLab's native Cell toolbar
+ * (top-right of the active cell, next to the move up/down buttons).
+ *
+ * Registered in index.ts via IToolbarWidgetRegistry.addFactory('Cell', ...);
+ * the toolbar factory passes the owning Cell, so the cell arrives via the
+ * constructor instead of being resolved from `this.parent` on attach.
+ */
+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 } from '../api/opencode_client';
+import { extractCellContext } from '../context/cell_context';
+import type {
+  CellContext,
+  OpenCodeMode,
+  OpenCodeRequest,
+  OpenCodeResponse,
+  OpenCodeSettings
+} from '../types';
+
+// Module-level runtime injection (set by index.ts after settings load).
+let _settings: OpenCodeSettings | null = null;
+let _serverSettings: ServerConnection.ISettings | null = null;
+
+export function setOpenCodeRuntime(args: {
+  settings: OpenCodeSettings;
+  serverSettings: ServerConnection.ISettings;
+}): void {
+  _settings = args.settings;
+  _serverSettings = args.serverSettings;
+}
+
+type Status = 'idle' | 'loading';
+
+export class OpenCodeCellActions extends Widget {
+  private _cell: CodeCell;
+  private _context: CellContext | null = null;
+  private _status: Status = 'idle';
+
+  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._onModelChange();
+  }
+
+  dispose(): void {
+    if (this.isDisposed) {
+      return;
+    }
+    this._cell.model.contentChanged.disconnect(this._onModelChange, this);
+    this._cell.model.stateChanged.disconnect(this._onModelChange, this);
+    super.dispose();
+  }
+
+  private _onModelChange(): void {
+    this._context = extractCellContextFromCell(this._cell);
+    this._render();
+  }
+
+  private _render(): void {
+    const node = this.node;
+    node.textContent = '';
+
+    const hasError = this._context?.error != null;
+    const loading = this._status === 'loading';
+    const baseDisabled = !this._context || loading;
+
+    const mkBtn = (
+      label: string,
+      mode: OpenCodeMode,
+      disabled: boolean
+    ): HTMLButtonElement => {
+      const b = document.createElement('button');
+      b.className = `opencode-btn opencode-btn-${mode}`;
+      b.textContent = label;
+      b.disabled = disabled;
+      b.title = disabled
+        ? loading
+          ? 'OpenCode: 请求中…'
+          : 'OpenCode: 等待 cell 上下文…'
+        : label;
+      b.addEventListener('click', () => {
+        void this._onClick(mode);
+      });
+      return b;
+    };
+
+    node.appendChild(mkBtn('✨ 优化', 'optimize', baseDisabled));
+    node.appendChild(mkBtn('🐛 排错', 'fix', baseDisabled || !hasError));
+    node.appendChild(mkBtn('🪄 编辑', 'edit', baseDisabled));
+  }
+
+  private async _onClick(mode: OpenCodeMode): Promise<void> {
+    if (!this._context) {
+      return;
+    }
+    if (!_settings || !_serverSettings) {
+      Notification.error('OpenCode 运行时未初始化，请检查 settings');
+      return;
+    }
+
+    let prompt = '';
+    if (mode === 'edit') {
+      const input = window.prompt('请输入编辑指令：');
+      if (input === null) {
+        return;
+      }
+      prompt = input;
+    }
+
+    const request: OpenCodeRequest = {
+      mode,
+      prompt,
+      context: this._context,
+      providerId: _settings.opencodeProvider || undefined,
+      modelId: _settings.opencodeModel || undefined
+    };
+
+    this._status = 'loading';
+    this._render();
+
+    try {
+      const resp = await callOpenCodeEdit(request, _serverSettings);
+      this._handleResponse(resp);
+    } catch (e) {
+      this._status = 'idle';
+      this._render();
+      Notification.error(`OpenCode ${mode} 失败: ${(e as Error).message}`);
+    }
+  }
+
+  private _handleResponse(resp: OpenCodeResponse): void {
+    this._status = 'idle';
+    this._render();
+    if (resp.ok) {
+      const len = resp.finalSource.length;
+      Notification.info(
+        `OpenCode ${resp.mode} 完成 (${len} chars). ` +
+          `Diff 面板将在 Slice 4 中提供。Session: ${resp.sessionId.slice(0, 8)}…`
+      );
+    } else {
+      Notification.error(`OpenCode 错误: ${resp.error}`);
+    }
+  }
+}
+
+/**
+ * Resolve a CodeCell's parent NotebookPanel by walking the parent chain,
+ * then build the CellContext. (Unchanged from the old footer helper; the
+ * `Widget.findParent` helper was removed in @lumino/widgets 2.x.)
+ */
+function extractCellContextFromCell(cell: CodeCell): CellContext | null {
+  let node: Widget | null = cell.parent;
+  let notebookPanel: NotebookPanel | null = null;
+  while (node) {
+    // Use duck-typing: a notebook panel has `context.path` and `content.widgets`.
+    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);
+}