diff --git a/changelog.d/2663-parallel-node-id.fixed.md b/changelog.d/2663-parallel-node-id.fixed.md
new file mode 100644
index 000000000..6331140e4
--- /dev/null
+++ b/changelog.d/2663-parallel-node-id.fixed.md
@@ -0,0 +1 @@
+Adding three or more Bots to one Parallel step in the New workflow dialog no longer gives two of them the same node id, so Create succeeds instead of failing with `Node n2 is listed twice` ([#2663](https://github.com/ThinkFlowLab/FlyBot/issues/2663)).
diff --git a/plugins/workflow/client.js b/plugins/workflow/client.js
index 0a83ccd0d..ce5a36cf6 100644
--- a/plugins/workflow/client.js
+++ b/plugins/workflow/client.js
@@ -1601,7 +1601,9 @@ window.__ModuleLoader__.load({
         const bot = locals.find(item => item.id === botId)
         if (!bot) return
         setSteps(list => {
-          const node = { id: `n${list.length + 1}`, botId: bot.id, name: bot.name, role: bot.role ?? '' }
+          // Parallel joins the last layer, so the layer count stops moving; allocate over the
+          // flat node list or a third Bot takes the second one's id and the host refuses (#2663).
+          const node = { id: nextNodeId(list.flat()), botId: bot.id, name: bot.name, role: bot.role ?? '' }
           if (parallel && list.length > 0) {
             const next = list.slice()
             next[next.length - 1] = [...next[next.length - 1], node]
diff --git a/plugins/workflow/test/client.test.js b/plugins/workflow/test/client.test.js
index 664df980e..ffc68d9fc 100644
--- a/plugins/workflow/test/client.test.js
+++ b/plugins/workflow/test/client.test.js
@@ -3,7 +3,7 @@
 import assert from 'node:assert/strict'
 import { readFileSync } from 'node:fs'
 import { test } from 'node:test'
-import { cleanTools } from '../src/graph.js'
+import { cleanTools, validateGraph } from '../src/graph.js'
 
 import { allThemes } from '../../../core/src/client/themes.js'
 
@@ -3891,6 +3891,78 @@ test('#2193: a refused create keeps its dialog open and shows the host sentence
   view.unmount()
 })
 
+// #2663: `CreateModal.add` took the node id from the layer count (`n${list.length + 1}`), but
+// with Parallel ticked a new Bot joins the last layer, so the layer count stopped moving and the
+// third Bot was given the second one's id (`n1,n2,n2`). Node ids are the graph's unique key, so
+// `workflow/create` refused the whole dialog with `Node n2 is listed twice`.
+// What `workflow/create` receives is the graph the host validates, so these drive the dialog the
+// way a user does and check the body against `src/graph.js` itself.
+const CREATE_BOTS = [
+  { id: 'b1', name: 'One' },
+  { id: 'b2', name: 'Two' },
+  { id: 'b3', name: 'Three' },
+]
+
+async function mountCreateDialog(bots = CREATE_BOTS) {
+  const calls = []
+  const call = async (name, body) => {
+    calls.push({ name, body })
+    if (name === 'workflow/state') return { workflows: [], templates: [] }
+    return { ok: true, workflows: [] }
+  }
+  const view = mount(client.Section, { roster: { bots }, call, actions: {} })
+  await settle()
+  button(view.tree, 'New').props.onClick()
+  await settle()
+  const dialog = () => findAll(view.tree, node => node.props?.role === 'dialog')[0]
+  const addBot = async (botId) => {
+    findAll(dialog(), node => node.type === 'select')[0].props.onChange({ target: { value: botId } })
+    await settle()
+    button(dialog(), 'Add a Bot').props.onClick()
+    await settle()
+  }
+  const create = async (name) => {
+    findAll(dialog(), node => node.type === 'input' && node.props?.type !== 'checkbox')[0].props.onChange({ target: { value: name } })
+    await settle()
+    findAll(dialog(), node => node.type === 'button' && node.props?.className === 'wf-btn wf-dark')[0].props.onClick()
+    await settle()
+  }
+  const sent = () => calls.find(item => item.name === 'workflow/create')?.body
+  return { view, dialog, addBot, create, sent }
+}
+
+test('#2663: three Bots added under Parallel get three distinct node ids and a graph the host accepts', async (t) => {
+  const dialog = await mountCreateDialog()
+  t.after(() => dialog.view.unmount())
+  findAll(dialog.dialog(), node => node.type === 'input' && node.props?.type === 'checkbox')[0].props.onChange({ target: { checked: true } })
+  await settle()
+  await dialog.addBot('b1')
+  await dialog.addBot('b2')
+  await dialog.addBot('b3')
+  await dialog.create('Lane A')
+  const body = dialog.sent()
+  assert.ok(body, 'Create was submitted')
+  const ids = body.nodes.map(node => node.id)
+  assert.equal(new Set(ids).size, 3, `three Bots in one Parallel step got ${ids.join(',')}`)
+  assert.deepEqual(body.layers, [ids], 'Parallel keeps the three Bots in one step')
+  assert.doesNotThrow(() => validateGraph({ nodes: body.nodes, layers: body.layers }), 'the host must accept the graph Create sent')
+  assert.deepEqual(body.nodes.map(node => node.name), ['One', 'Two', 'Three'])
+})
+
+test('#2663: sequential adding still numbers the nodes n1, n2, n3', async (t) => {
+  const dialog = await mountCreateDialog()
+  t.after(() => dialog.view.unmount())
+  await dialog.addBot('b1')
+  await dialog.addBot('b2')
+  await dialog.addBot('b3')
+  await dialog.create('Lane A')
+  const body = dialog.sent()
+  assert.ok(body, 'Create was submitted')
+  assert.deepEqual(body.nodes.map(node => node.id), ['n1', 'n2', 'n3'])
+  assert.deepEqual(body.layers, [['n1'], ['n2'], ['n3']], 'each Bot keeps its own step')
+  assert.doesNotThrow(() => validateGraph({ nodes: body.nodes, layers: body.layers }))
+})
+
 // #2200: the sidebar list is the other face of the same read-only window. #2187 took the edit
 // surface off the graph page; the list still offered New, the row menu's Rename and Delete, and
 // the Hand a task row, and the host refused every one of them behind the mask.