diff --git a/changelog.d/1856-workflow-project.added.md b/changelog.d/1856-workflow-project.added.md
new file mode 100644
index 000000000..7e93bedc7
--- /dev/null
+++ b/changelog.d/1856-workflow-project.added.md
@@ -0,0 +1 @@
+We worked a workflow (a workflow now belongs to a Project: its definition carries projectId, the run is bound when it starts, and Settings shows the Project) — [#1856](https://github.com/ThinkFlowLab/FlyBot/issues/1856).
diff --git a/core/src/host/hooks.js b/core/src/host/hooks.js
index d36c72b8d..2d8b9e021 100644
--- a/core/src/host/hooks.js
+++ b/core/src/host/hooks.js
@@ -1349,6 +1349,21 @@ export function install(rt) {
         return rt.taskCounters?.(query) ?? { roles: {}, runs: {} }
       },
     },
+    // #1856: a workflow run belongs to a Project, and the plugin cannot write host state. A host
+    // without this seam answers `undefined` and never throws: the run stays unbound and keeps today
+    // behavior. The write goes through the same `bindProject` the endpoint uses, so a run bound
+    // from an assign and a run bound from Settings cannot disagree.
+    projects: {
+      read(id) {
+        return typeof rt.readProject === "function" ? rt.readProject(String(id ?? '')) ?? undefined : undefined
+      },
+      async bindRun(runId, projectId) {
+        if (typeof rt.bindProject !== "function") return undefined
+        const project = rt.bindProject({ kind: 'run', id: String(runId ?? ''), projectId })
+        await rt.save?.()
+        return project ?? undefined
+      },
+    },
     tools,
     api,
     outcomeOf: exchangeId => outcomes.get(exchangeId),
diff --git a/core/test/project-run-seam.test.js b/core/test/project-run-seam.test.js
new file mode 100644
index 000000000..ae82467b6
--- /dev/null
+++ b/core/test/project-run-seam.test.js
@@ -0,0 +1,49 @@
+// #1856: a workflow run belongs to a Project, but the plugin cannot write host state. `bindRun`
+// is that one seam: it writes `state.projectRuns` through the same `bindProject` the endpoint
+// uses, refuses an unknown Project, and a host without it answers `undefined` instead of throwing.
+import assert from 'node:assert/strict'
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { test } from 'node:test'
+import { createRuntime } from '../index.js'
+import { fakeContext } from './fake-ctx.js'
+
+const seed = () => ({
+  version: 1,
+  mainBotIds: ['a'],
+  bots: { a: { id: 'a', name: 'Chief', role: 'Boss', sessionId: 'a', createdAt: 1 } },
+  rooms: {}, agents: {}, exchanges: [], exchangeTurns: {}, questions: {}, prefs: {}, revision: 0,
+})
+
+async function start(t) {
+  const home = mkdtempSync(join(tmpdir(), 'ds-bot-project-run-'))
+  writeFileSync(join(home, 'state.json'), JSON.stringify(seed()))
+  const rt = createRuntime(fakeContext(), { home })
+  t.after(() => rmSync(home, { recursive: true, force: true, maxRetries: 5 }))
+  await rt.load()
+  return rt
+}
+
+test('#1856: bindRun writes the run binding the board reads', async (t) => {
+  const rt = await start(t)
+  const project = rt.createProject({ name: 'FlyBot 开发' })
+  const bound = await rt.flybot.projects.bindRun('run-abc', project.id)
+  assert.equal(bound.id, project.id)
+  assert.equal(rt.state.projectRuns['run-abc'], project.id)
+  assert.equal(rt.flybot.projects.read(project.id).name, 'FlyBot 开发')
+})
+
+test('#1856: bindRun refuses an unknown Project and writes nothing', async (t) => {
+  const rt = await start(t)
+  await assert.rejects(() => rt.flybot.projects.bindRun('run-abc', 'project-missing'), /Unknown Project project-missing/)
+  assert.equal(rt.state.projectRuns['run-abc'], undefined)
+})
+
+test('#1856: a host without the seam answers undefined instead of throwing', async (t) => {
+  const rt = await start(t)
+  rt.readProject = undefined
+  rt.bindProject = undefined
+  assert.equal(rt.flybot.projects.read('project-1'), undefined)
+  assert.equal(await rt.flybot.projects.bindRun('run-abc', 'project-1'), undefined)
+})
diff --git a/docs/subsystems/core-host.md b/docs/subsystems/core-host.md
index d7d1e27ab..4ac34bc95 100644
--- a/docs/subsystems/core-host.md
+++ b/docs/subsystems/core-host.md
@@ -769,3 +769,7 @@ the host side only, so the tier stays T2 and `core/src/shared/` is untouched.
 ## Project metrics (#1829)
 
 `core/src/host/project-metrics.js` answers the Project board's seven numbers: PRs opened and merged today, issues opened and closed today, and the seven-day medians of PR merge, issue close and task completion durations. The four day counts compare `created_at` / `merged_at` / `closed_at` against the reader's own time zone (`Intl.DateTimeFormat`), not the host clock, and the local task half reads `createdAt` / `completedAt` from `state.tasks`. The numbers ride on the existing `project-board` endpoint (`store.js` carries the `metrics` section beside the rows), which passes the host secret store's `GITHUB_TOKEN` and the reader's time zone from the request, requires the Project, and answers `ok: false` with `null` values when the credential is missing or a read fails — the client paints `—`, never `0`. One five-minute in-process cache keys on repository, time zone and window, so a hit spends no source call; a failed read is not cached. `runningOf` projects a claimed card into the running table's row (who, claim age, source, last activity).
+
+## The Project run seam (#1856)
+
+`fb.projects` is the one seam a workflow run's Project binding goes through. `read(id)` answers the Project record or `undefined`; `bindRun(runId, projectId)` writes `state.projectRuns[runId]` through `bindProject({ kind: 'run', … })` — the path the `project-bind` endpoint already uses — and saves. An unknown Project throws the store's own refusal, so the caller (the workflow plugin) treats it as a refused binding and keeps the run. A host without either function answers `undefined` and never throws, which is what an older plugin instance sees.
diff --git a/docs/subsystems/workflow.md b/docs/subsystems/workflow.md
index 775cf4293..a166cddaf 100644
--- a/docs/subsystems/workflow.md
+++ b/docs/subsystems/workflow.md
@@ -75,3 +75,11 @@ Core never reads `$DSH_HOME/bot/flybot-workflow`. The plugin registers `flybot.t
 A connector a Bot switched off is not reopened by a Workflow, whichever surface started the run. A run records the Bots whose switches cap it, both in `cappedBy`: the Bot whose `run_workflow` call started it, and the Bot that saved the graph (`authoredBy` on the workflow record, set by `define_workflow` and by any save that names a Bot). A run Bot carries no `createdBy` (#1582): the roster reads that field as "a Bot made this Bot" and would start the run Bot on its maker's model, so the caller travels in `cappedBy` only — a ceiling, not a parent. Every node's run Bot carries `cappedBy` — the caller, else the graph's author — and `core/src/host/connector-access.js` intersects the node's `tools` with those switches, so a node that names a connector its caller or author turned off is refused with `turned off for <name>; the step's tools list cannot turn it back on`, and the tool is masked out of the run Bot's list too. A run nobody's tool call started (the board's `ingest`, the canvas, the `workflow/*` API) has no caller and is capped by the graph's author alone; a save with no Bot behind it records no author, which is the owner's own edit and leaves no ceiling; a graph saved before this has none either. `visibleTo` on `run_workflow`/`define_workflow` is unchanged: the ceiling is the fix, not limiting who may define a Workflow.
 - **Strict order (#1729).** A graph may carry `strict: true` (normalized to a boolean on the record). A strict graph starts one node at a time in declared order: `startFrontier` keeps only the first ready node running and leaves its ready siblings `queued`, so no parallel fan-out happens even when two nodes share a rank. They start when the node before them finishes, in list order. The default is unchanged — a graph without the flag still fans out — and the release-shaped delivery template passes unchanged. A second start against the persisted status after a crash between a claim and its result starts nothing that is already running and reaches no downstream node early, so no second downstream task is minted. The strict release graph (build → test → publish) and its refusal of a node whose required input was never produced are the regression (#1730). Tests: `plugins/workflow/test/strict-order.test.js`, `plugins/workflow/test/strict-release-dag.test.js`.
 - **Lease and delivery reads go through the host (#1729).** The plugin reads a card's lease with `fb.tasks.lease(taskId)` (`{ holder, takenAt, expiresAt, live, heldBy }`, or `undefined`) and the per-role/per-run delivery and resource counts with `fb.tasks.counters({ role, run })`. Both are host reads of the existing task rows (`rt.taskLease`, `rt.taskCounters`); the plugin keeps no copy, so an expired lease looks expired to both sides at once.
+
+## A workflow belongs to a Project (#1856)
+
+A workflow record carries `projectId`. `saveGraph` is the only writer: a non-empty value must name an existing Project (`fb.projects.read`, which reads the host's `readProject`) or the whole save is refused and nothing is written; `null` clears it; omitting the field keeps what is stored.
+
+- The Settings page names the Project on every sidebar row (a workflow with none reads `Unassigned`, zh 未归属), offers one Project filter above the list (`All Projects` plus each Project plus the unassigned rows), and carries a Project picker in the graph editor; the picker saves through the same `workflow/graph` call that carries the nodes and edges, and an empty choice sends `null`. The picker is fed by the host `projects` endpoint, so it lists what the core store holds and never a second copy.
+
+A run is bound at creation, through `fb.projects.bindRun(runId, projectId)` — the seam beside `fb.tasks.onProjectProvider`. `assign()` resolves the Project once (the call's own `projectId` wins over the workflow's) and carries it with the task, so a parked run binds when it actually starts. The binding goes through the host's `bindProject({ kind: 'run', … })`, the same path the `project-bind` endpoint uses, so the Project board and Settings cannot disagree. An unknown Project, or a host without the seam, leaves the run unbound and logs once; it never stops the run from starting.
diff --git a/patches/ds-bot/files/src/host/hooks.js b/patches/ds-bot/files/src/host/hooks.js
index d36c72b8d..2d8b9e021 100644
--- a/patches/ds-bot/files/src/host/hooks.js
+++ b/patches/ds-bot/files/src/host/hooks.js
@@ -1349,6 +1349,21 @@ export function install(rt) {
         return rt.taskCounters?.(query) ?? { roles: {}, runs: {} }
       },
     },
+    // #1856: a workflow run belongs to a Project, and the plugin cannot write host state. A host
+    // without this seam answers `undefined` and never throws: the run stays unbound and keeps today
+    // behavior. The write goes through the same `bindProject` the endpoint uses, so a run bound
+    // from an assign and a run bound from Settings cannot disagree.
+    projects: {
+      read(id) {
+        return typeof rt.readProject === "function" ? rt.readProject(String(id ?? '')) ?? undefined : undefined
+      },
+      async bindRun(runId, projectId) {
+        if (typeof rt.bindProject !== "function") return undefined
+        const project = rt.bindProject({ kind: 'run', id: String(runId ?? ''), projectId })
+        await rt.save?.()
+        return project ?? undefined
+      },
+    },
     tools,
     api,
     outcomeOf: exchangeId => outcomes.get(exchangeId),
diff --git a/patches/ds-bot/files/test/project-run-seam.test.js b/patches/ds-bot/files/test/project-run-seam.test.js
new file mode 100644
index 000000000..ae82467b6
--- /dev/null
+++ b/patches/ds-bot/files/test/project-run-seam.test.js
@@ -0,0 +1,49 @@
+// #1856: a workflow run belongs to a Project, but the plugin cannot write host state. `bindRun`
+// is that one seam: it writes `state.projectRuns` through the same `bindProject` the endpoint
+// uses, refuses an unknown Project, and a host without it answers `undefined` instead of throwing.
+import assert from 'node:assert/strict'
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { test } from 'node:test'
+import { createRuntime } from '../index.js'
+import { fakeContext } from './fake-ctx.js'
+
+const seed = () => ({
+  version: 1,
+  mainBotIds: ['a'],
+  bots: { a: { id: 'a', name: 'Chief', role: 'Boss', sessionId: 'a', createdAt: 1 } },
+  rooms: {}, agents: {}, exchanges: [], exchangeTurns: {}, questions: {}, prefs: {}, revision: 0,
+})
+
+async function start(t) {
+  const home = mkdtempSync(join(tmpdir(), 'ds-bot-project-run-'))
+  writeFileSync(join(home, 'state.json'), JSON.stringify(seed()))
+  const rt = createRuntime(fakeContext(), { home })
+  t.after(() => rmSync(home, { recursive: true, force: true, maxRetries: 5 }))
+  await rt.load()
+  return rt
+}
+
+test('#1856: bindRun writes the run binding the board reads', async (t) => {
+  const rt = await start(t)
+  const project = rt.createProject({ name: 'FlyBot 开发' })
+  const bound = await rt.flybot.projects.bindRun('run-abc', project.id)
+  assert.equal(bound.id, project.id)
+  assert.equal(rt.state.projectRuns['run-abc'], project.id)
+  assert.equal(rt.flybot.projects.read(project.id).name, 'FlyBot 开发')
+})
+
+test('#1856: bindRun refuses an unknown Project and writes nothing', async (t) => {
+  const rt = await start(t)
+  await assert.rejects(() => rt.flybot.projects.bindRun('run-abc', 'project-missing'), /Unknown Project project-missing/)
+  assert.equal(rt.state.projectRuns['run-abc'], undefined)
+})
+
+test('#1856: a host without the seam answers undefined instead of throwing', async (t) => {
+  const rt = await start(t)
+  rt.readProject = undefined
+  rt.bindProject = undefined
+  assert.equal(rt.flybot.projects.read('project-1'), undefined)
+  assert.equal(await rt.flybot.projects.bindRun('run-abc', 'project-1'), undefined)
+})
diff --git a/plugins/workflow/client.js b/plugins/workflow/client.js
index 97e73b55e..10c31c611 100644
--- a/plugins/workflow/client.js
+++ b/plugins/workflow/client.js
@@ -22,6 +22,11 @@ window.__ModuleLoader__.load({
     const ZH = {
       Workflows: 'Workflows',
       New: '新建',
+      Project: '项目',
+      Unassigned: '未归属',
+      'All Projects': '全部项目',
+      'Filter by Project': '按项目筛选',
+      'No workflows in this Project': '这个项目下还没有 Workflow',
       'Hand a task to a Workflow': '把任务交给 Workflow',
       'A task can go to a Workflow, not only to one Bot. The Workflow then runs each Bot in order, or side by side.': '任务不再只能交给单个 Bot —— 交给 Workflow 后，会按固定流程依次（或并行）交给各个 Bot 执行。',
       'Pick a task card': '从 Tasks 看板选择任务卡片',
@@ -1501,6 +1506,7 @@ window.__ModuleLoader__.load({
       const [error, setError] = useState('')
       const [loading, setLoading] = useState(true)
       const [attempt, setAttempt] = useState(0)
+      const [projects, setProjects] = useState([])
 
       useEffect(() => {
         let gone = false
@@ -1523,6 +1529,16 @@ window.__ModuleLoader__.load({
         return undefined
       }, [])
 
+      useEffect(() => {
+        const host = globalThis.__flybot__?.host
+        if (typeof host !== 'function') return undefined
+        let gone = false
+        void host('projects', {}).then(listing => {
+          if (!gone && Array.isArray(listing?.projects)) setProjects(listing.projects)
+        }).catch(() => {})
+        return () => { gone = true }
+      }, [])
+
       const workflows = pack?.workflows ?? []
       const current = workflows.find(item => item.id === workflowId) ?? workflows[0]
       const nodes = current?.nodes ?? []
@@ -1541,6 +1557,16 @@ window.__ModuleLoader__.load({
       const updateNode = (nodeId, updates) => {
         save(nodes.map(item => item.id === nodeId ? { ...item, ...updates } : item), edges)
       }
+
+      // The binding is stored with the graph it belongs to: one save carries the
+      // nodes, the edges and the Project, and null clears it.
+      const setProject = (projectId) => {
+        if (!current) return
+        void settledCall(call, 'workflow/graph', { workflowId: current.id, nodes, edges, projectId }, 'Could not save this workflow').then(value => {
+          if (value?.ok === false) { setError(value.error ?? tr('Could not save this workflow')); return }
+          if (value?.workflows) { setPack(value); setError('') }
+        })
+      }
       
       const [edgeForm, setEdgeForm] = useState({ from: '', to: '', kind: 'forward', max: 5, until: { output: '', eq: '' } })
       const [toolsDraft, setToolsDraft] = useState(null)
@@ -1594,6 +1620,15 @@ window.__ModuleLoader__.load({
                 value: current.id,
                 onChange: (event) => { setWorkflowId(event.target.value); setSelectedNode(null) },
               }, workflows.map(item => h('option', { key: item.id, value: item.id }, item.name)))),
+            h('label', { className: 'wf-field' },
+              h('span', null, tr('Project')),
+              h('select', {
+                'aria-label': tr('Project'),
+                value: current.projectId ?? '',
+                onChange: (event) => setProject(event.target.value || null),
+              },
+                h('option', { value: '' }, tr('Unassigned')),
+                projects.map(project => h('option', { key: project.id, value: project.id }, project.name)))),
             h('label', { className: 'wf-field' },
               h('span', null, tr('Model')),
               h('select', {
@@ -1847,6 +1882,8 @@ window.__ModuleLoader__.load({
       const [rowMenu, setRowMenu] = useState(null)
       const [renaming, setRenaming] = useState(null)
       const [deleting, setDeleting] = useState(null)
+      const [projects, setProjects] = useState([])
+      const [projectFilter, setProjectFilter] = useState('')
       const stageLeft = useConversationInset()
 
       const stageCall = (name, body, fallback) => settledCall(call, name, body, fallback)
@@ -1870,6 +1907,12 @@ window.__ModuleLoader__.load({
         void refresh().then(async () => {
           const host = globalThis.__flybot__?.host
           if (gone || typeof host !== 'function') return
+          try {
+            const listing = await host('projects', {})
+            if (!gone && Array.isArray(listing?.projects)) setProjects(listing.projects)
+          } catch (loadError) {
+            void loadError
+          }
           try {
             const rows = await host('tasks', {})
             if (!Array.isArray(rows) || gone) return
@@ -1920,6 +1963,10 @@ window.__ModuleLoader__.load({
 
       const workflows = pack?.workflows ?? []
       const open = workflows.find(item => item.id === openId) ?? null
+      const projectName = (id) => projects.find(project => project.id === id)?.name ?? ''
+      const shown = projectFilter === ''
+        ? workflows
+        : workflows.filter(item => (projectFilter === 'none' ? !item.projectId : item.projectId === projectFilter))
 
       useEffect(() => {
         if (!open) { setFocusedRunId(null); return }
@@ -2059,10 +2106,21 @@ window.__ModuleLoader__.load({
         h('div', { className: 'wf-sec' },
           h('span', null, tr('Workflows')),
           h('button', { type: 'button', className: 'wf-new', onClick: () => setCreating(true) }, tr('New'))),
+        workflows.length > 0 ? h('label', { className: 'wf-filter' },
+          h('span', null, tr('Filter by Project')),
+          h('select', {
+            'aria-label': tr('Filter by Project'),
+            value: projectFilter,
+            onChange: (event) => setProjectFilter(event.target.value),
+          },
+            h('option', { value: '' }, tr('All Projects')),
+            projects.map(project => h('option', { key: project.id, value: project.id }, project.name)),
+            h('option', { value: 'none' }, tr('Unassigned')))) : null,
         pack?.tasksWired === false ? h('div', { className: 'wf-wiring', role: 'status' },
           tr('This host does not pass task writes to Workflows, so a card on the board cannot start a run.')) : null,
         workflows.length === 0 && !readError ? h('div', { className: 'wf-muted' }, tr('No workflows yet.')) : null,
-        workflows.map(item => h('button', {
+        workflows.length > 0 && shown.length === 0 ? h('div', { className: 'wf-muted' }, tr('No workflows in this Project')) : null,
+        shown.map(item => h('button', {
           key: item.id, type: 'button', className: `wf-row ${openId === item.id ? 'on' : ''}`,
           onClick: () => { setOpenId(item.id) },
           onContextMenu: (event) => {
@@ -2073,7 +2131,8 @@ window.__ModuleLoader__.load({
         },
           h('span', { className: 'wf-ico' }, h(MiniFlowchart, { workflow: item, compact: true })),
           h('span', { className: 'wf-txt' },
-            h('span', { className: 'wf-t1' }, item.name, h('span', { className: 'wf-badge' }, 'Workflow')),
+            h('span', { className: 'wf-t1' }, item.name, h('span', { className: 'wf-badge' }, 'Workflow'),
+              h('span', { className: `wf-proj${projectName(item.projectId) ? '' : ' none'}` }, projectName(item.projectId) || tr('Unassigned'))),
             h('span', { className: 'wf-t2' }, sidebarPreview(item))),
           (item.activeCount ?? 0) > 0 ? h('span', { className: 'wf-live', 'aria-hidden': true }) : null)),
         h('button', { type: 'button', className: 'wf-row wf-assign-row', onClick: () => { setAssignOpen(true); void loadTasks() } },
@@ -2173,6 +2232,10 @@ window.__ModuleLoader__.load({
     const CSS = `
 .wf-sec{display:flex;align-items:center;justify-content:space-between;padding:12px 8px 4px;font-size:11px;color:var(--bt-ink-3,#9a9a9a)}
 .wf-new{color:var(--bt-accent,#4d6bfe);background:none;border:0;cursor:pointer;font:inherit;font-size:11px}
+.wf-filter{display:flex;align-items:center;gap:8px;padding:0 8px 4px;font-size:11px;color:var(--bt-ink-3,#9a9a9a)}
+.wf-filter select{flex:1;min-width:0;font:inherit;font-size:11px;background:transparent;color:inherit;border:1px solid var(--bt-line,rgba(20,20,20,.08));border-radius:6px;padding:2px 4px}
+.wf-proj{font-size:9.5px;padding:0 5px;border-radius:4px;background:var(--bt-tag-bg,rgba(20,20,20,.06));color:var(--bt-tag-ink,rgba(20,20,20,.58));line-height:15px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:120px}
+.wf-proj.none{opacity:.7;font-style:italic}
 .wf-row{display:flex;align-items:center;gap:10px;width:100%;padding:8px;border:0;border-radius:8px;background:transparent;color:inherit;font:inherit;text-align:left;cursor:pointer}
 .wf-row.on,.wf-row:hover{background:var(--bt-hover,rgba(119,119,119,.09))}
 .wf-txt{min-width:0;flex:1}
diff --git a/plugins/workflow/index.js b/plugins/workflow/index.js
index a90fabd9d..53398d782 100644
--- a/plugins/workflow/index.js
+++ b/plugins/workflow/index.js
@@ -96,6 +96,10 @@ export function apply(ctx, config = {}) {
     readOnly: () => fb.readOnly?.() === true,
     warn: (...args) => fb.warn?.(...args),
     tasksWired,
+    // #1856: the host owns the Project record and the run binding; a host without the seam answers
+    // undefined and the service leaves the run unbound.
+    readProject: id => fb.projects?.read?.(id),
+    bindRun: (runId, projectId) => fb.projects?.bindRun?.(runId, projectId),
     ...lifecycle,
   })
   void service.reap?.().catch(error => fb.warn?.('flybot-workflow: reap failed: %s', error))
diff --git a/plugins/workflow/src/service.js b/plugins/workflow/src/service.js
index e44db96a9..ff8fb1e78 100644
--- a/plugins/workflow/src/service.js
+++ b/plugins/workflow/src/service.js
@@ -153,6 +153,9 @@ function blankRun(workflow, task, now, history = []) {
 
 export function createWorkflowService({
   dir, persist = true, now = () => Date.now(), bots = () => [], readOnly = () => false, warn = () => {}, tasksWired = false, spawn, release, dispatch,
+  // #1856: the host's Project seam. `readProject(id)` answers the record or null; `bindRun(runId,
+  // projectId)` binds a run at creation. A host without either leaves the run unbound.
+  readProject, bindRun,
   setTimer = (fn, ms) => setTimeout(fn, ms), clearTimer = handle => clearTimeout(handle),
 } = {}) {
   const file = dir ? join(dir, FILE) : null
@@ -332,6 +335,8 @@ export function createWorkflowService({
         trigger: item.trigger ?? 'manual',
         scheduleLabel: item.scheduleLabel ?? '',
         model: item.model ?? '',
+        // #1856: unowned is `null`, never a missing key, so the list and the editor agree.
+        projectId: item.projectId ?? null,
         nodes: item.nodes.map(node => publicNode(node, roster)),
         edges: (item.edges ?? []).map(publicEdge),
         layers: item.layers.map(layer => [...layer]),
@@ -733,7 +738,7 @@ export function createWorkflowService({
     }
     if (!best) return null
     const task = laneOf(best.item.id).queue.shift()
-    return { item: best.item, task: { id: task.id, title: task.title, ...(task.callerBotId ? { callerBotId: task.callerBotId } : {}) } }
+    return { item: best.item, task: { id: task.id, title: task.title, ...(task.callerBotId ? { callerBotId: task.callerBotId } : {}), ...(task.projectId ? { projectId: task.projectId } : {}) } }
   }
 
   function noteUnstarted(item, error) {
@@ -805,6 +810,24 @@ export function createWorkflowService({
     return runningOf(lane).some(run => run.task?.id === taskId) || lane.queue.some(task => task.id === taskId)
   }
 
+  // #1856: a run belongs to the Project its workflow names, or to the one the assign call named.
+  // A host without the seam, and a refused binding, leave the run unbound — the run still starts.
+  function bindRunProject(item, task, run) {
+    const projectId = cleanLine(task?.projectId ?? item?.projectId ?? '', 120)
+    if (projectId === '') return
+    if (typeof bindRun !== 'function') {
+      warnOnce('project-seam', 'flybot-workflow: this host has no project seam, so a run stays unbound')
+      return
+    }
+    const onError = error => warnOnce(`project-refused:${run.id}`, `flybot-workflow: run ${run.id} was refused Project ${projectId}: ${String(error?.message ?? error).slice(0, 200)}`)
+    try {
+      const bound = bindRun(run.id, projectId)
+      if (bound && typeof bound.then === 'function') bound.catch(onError)
+    } catch (error) {
+      onError(error)
+    }
+  }
+
   function beginRun(item, task, ephemeral) {
     const holes = missingProviders(item)
     if (holes.length > 0) return { ok: false, error: `Node ${holes[0].nodeId} input ${holes[0].name} has no upstream provider` }
@@ -823,6 +846,7 @@ export function createWorkflowService({
     ], at)
     const stepped = applyOp(item, run, { type: 'start' })
     run = stepped.run
+    bindRunProject(item, task, run)
     laneOf(item.id).active.push(run)
     push(item.id, stepped.lines, at)
     syncTimers(item, run)
@@ -876,6 +900,8 @@ export function createWorkflowService({
       queueSeq: state.queueSeq,
       // #1544: a parked run starts later without its caller in hand; keep it, or the ceiling is lost.
       ...(task.callerBotId ? { callerBotId: task.callerBotId } : {}),
+      // #1856: a parked run keeps the Project it was assigned with.
+      ...(task.projectId ? { projectId: task.projectId } : {}),
     })
     const ahead = lane.queue.length - 1
     push(item.id, [{
@@ -1115,6 +1141,11 @@ export function createWorkflowService({
       // and the API pass none, and the graph's author is the ceiling there.
       const callerBotId = cleanLine(body.callerBotId, 80)
       if (callerBotId) task.callerBotId = callerBotId
+      // #1856: the call's own Project wins over the workflow's; the run is bound when it is
+      // created, which for a parked task is later, so the choice travels with the task.
+      const wanted = body.projectId !== undefined ? body.projectId : item.projectId
+      const projectId = cleanLine(wanted ?? '', 120)
+      if (projectId !== '') task.projectId = projectId
       if (typeof spawn !== 'function') return enqueue(item, task)
       return hostSerial(() => enqueue(item, task))
     },
@@ -1417,6 +1448,13 @@ export function createWorkflowService({
         const authoredBy = cleanLine(body.callerBotId ?? body.authoredBy, 80) || undefined
         if (authoredBy) item.authoredBy = authoredBy
         else delete item.authoredBy
+        // #1856: `null` clears, omitted keeps, and a name must resolve — an unknown Project
+        // refuses the whole save before anything is touched, so a failed edit writes nothing.
+        const projectId = body.projectId === undefined ? undefined : body.projectId === null ? null : cleanLine(body.projectId, 120)
+        if (projectId !== undefined && projectId !== null) {
+          const project = typeof readProject === "function" ? readProject(projectId) : null
+          if (!project || typeof project !== "object") throw new Error(`Unknown Project ${projectId}`)
+        }
         const seated = seat(body.nodes, bots() ?? [])
         const seenBots = new Set()
         for (const node of seated) {
@@ -1458,6 +1496,10 @@ export function createWorkflowService({
         item.nodes = next.nodes
         item.edges = next.edges
         item.layers = next.layers
+        // Applied only once the graph validated and the runs settled, so a save that throws leaves
+        // neither the record nor the lane half-changed (#1856).
+        if (projectId === null) delete item.projectId
+        else if (projectId !== undefined) item.projectId = projectId
         for (const { run, names } of endedRuns) {
           lane.active = lane.active.filter(itemRun => itemRun.id !== run.id)
           lane.last = run
diff --git a/plugins/workflow/test/assign.test.js b/plugins/workflow/test/assign.test.js
index 7c865a6ad..1aca52d45 100644
--- a/plugins/workflow/test/assign.test.js
+++ b/plugins/workflow/test/assign.test.js
@@ -463,3 +463,69 @@ test('delete cleans up runs, logs, and routes', () => {
   assert.equal(deleted.ok, true)
   assert.ok(!deleted.workflows.some(item => item.id === laneId))
 })
+
+// #1856: a run belongs to the Project its workflow names, and the assign call may name another.
+// The binding lands when the run is created, which for a parked task is later than the assign —
+// so the choice travels with the task — and a refusal never keeps the run from starting.
+function projectService() {
+  const bound = []
+  const refusals = []
+  const svc = createWorkflowService({
+    persist: false,
+    now: () => 1_700_000_000_000,
+    bots: () => roster,
+    warn: message => refusals.push(message),
+    readProject: id => (id === 'project-1fe64499' || id === 'project-2' ? { id, name: 'FlyBot 开发' } : null),
+    bindRun: (runId, projectId) => {
+      if (projectId === 'project-unknown') throw new Error(`Unknown Project ${projectId}`)
+      bound.push({ runId, projectId })
+      return { id: projectId }
+    },
+  })
+  return { svc, bound, refusals }
+}
+
+function ownProject(svc, workflowId, projectId) {
+  const saved = svc.saveGraph({ workflowId, ...graphOf(svc, workflowId), projectId })
+  assert.equal(saved.ok, true, JSON.stringify(saved))
+}
+
+function graphOf(svc, workflowId) {
+  const item = svc.state().workflows.find(workflow => workflow.id === workflowId)
+  return { nodes: item.nodes, edges: item.edges }
+}
+
+test('#1856: a workflow carrying a Project binds the run it starts', () => {
+  const { svc, bound } = projectService()
+  ownProject(svc, DELIVERY_ID, 'project-1fe64499')
+  const state = svc.assign({ workflowId: DELIVERY_ID, taskId: '#1856a', title: 'Bind at creation' })
+  assert.equal(state.ok, true, JSON.stringify(state))
+  const run = delivery(state).run
+  assert.deepEqual(bound, [{ runId: run.id, projectId: 'project-1fe64499' }])
+})
+
+test('#1856: the Project named by the assign call wins over the workflow\'s own', () => {
+  const { svc, bound } = projectService()
+  ownProject(svc, DELIVERY_ID, 'project-1fe64499')
+  const state = svc.assign({ workflowId: DELIVERY_ID, taskId: '#1856b', title: 'Call wins', projectId: 'project-2' })
+  assert.equal(state.ok, true, JSON.stringify(state))
+  assert.deepEqual(bound, [{ runId: delivery(state).run.id, projectId: 'project-2' }])
+})
+
+test('#1856: a workflow with no Project binds nothing and behaves as before', () => {
+  const { svc, bound, refusals } = projectService()
+  const state = svc.assign({ workflowId: DELIVERY_ID, taskId: '#1856c', title: 'Unowned' })
+  assert.equal(state.ok, true, JSON.stringify(state))
+  assert.deepEqual(bound, [])
+  assert.deepEqual(refusals, [])
+  assert.equal(delivery(state).run.status, 'running')
+})
+
+test('#1856: a refused binding still starts the run', () => {
+  const { svc, bound, refusals } = projectService()
+  const state = svc.assign({ workflowId: DELIVERY_ID, taskId: '#1856d', title: 'Refused', projectId: 'project-unknown' })
+  assert.equal(state.ok, true, JSON.stringify(state))
+  assert.equal(delivery(state).run.status, 'running', 'the run started despite the refused binding')
+  assert.deepEqual(bound, [])
+  assert.ok(refusals.some(message => /refused Project project-unknown/.test(message)), refusals.join(' | '))
+})
diff --git a/plugins/workflow/test/client.test.js b/plugins/workflow/test/client.test.js
index 8ae782331..97c4e2459 100644
--- a/plugins/workflow/test/client.test.js
+++ b/plugins/workflow/test/client.test.js
@@ -2921,3 +2921,82 @@ test('the drawer Edit plane encloses the delivery parallel pair in a frame its l
   assert.ok(labelMax >= LABEL_ONE_LINE, `the label is capped at ${labelMax}px, so 'Parallel branches · Merge after all pass' wraps`)
   view.unmount()
 })
+
+// #1856: a Workflow belongs to a Project. The sidebar row names it, a workflow
+// with none says so, and one filter narrows the list to a single Project.
+test('#1856: the sidebar names each workflow Project and filters to one Project', async () => {
+  const alone = delivery()
+  alone.projectId = 'proj-atlas'
+  const loose = { ...delivery(), id: 'loose', name: 'Loose flow' }
+  const call = async (name) => {
+    if (name === 'workflow/state') return { workflows: [alone, loose], templates: [] }
+    return { ok: true, workflows: [alone, loose] }
+  }
+  const prevHost = globalThis.__flybot__
+  globalThis.__flybot__ = {
+    t: key => (key === 'Tasks' ? '任务' : key),
+    host: async (channel) => (channel === 'projects' ? { projects: [{ id: 'proj-atlas', name: 'Atlas' }] } : []),
+  }
+  try {
+    const view = mount(client.Section, { roster: { bots: [] }, call, actions: {} })
+    await settle()
+    const row = (name) => findAll(view.tree, node => node.type === 'button' && String(node.props?.className ?? '').includes('wf-row') && textOf(node).includes(name))[0]
+    assert.match(textOf(row('发布交付流水线')), /Atlas/, 'the row names the Project the workflow belongs to')
+    assert.match(textOf(row('Loose flow')), /未归属/, 'a workflow with no Project says so')
+
+    const filter = () => findAll(view.tree, node => node.props?.['aria-label'] === '按项目筛选')[0]
+    assert.ok(filter(), 'one Project filter sits above the list')
+    filter().props.onChange({ target: { value: 'proj-atlas' } })
+    await settle()
+    assert.ok(row('发布交付流水线'), 'the chosen Project keeps its own workflow')
+    assert.equal(row('Loose flow'), undefined, 'another Project is filtered out')
+    filter().props.onChange({ target: { value: 'none' } })
+    await settle()
+    assert.ok(row('Loose flow'), 'unowned workflows are a filter of their own')
+    assert.equal(row('发布交付流水线'), undefined)
+    view.unmount()
+  } finally {
+    globalThis.__flybot__ = prevHost
+  }
+})
+
+// #1856: the editor binds the graph to a Project through the same save that
+// carries the nodes and edges, and an empty choice clears it.
+test('#1856: the settings picker binds a workflow to a Project and clears it', async () => {
+  const graph = delivery()
+  const calls = []
+  const call = async (name, body) => {
+    calls.push({ name, body })
+    if (name === 'workflow/state') return { workflows: [graph] }
+    if (name === 'workflow/graph') { graph.projectId = body.projectId; return { ok: true, workflows: [{ ...graph }] } }
+    return { ok: true, workflows: [graph] }
+  }
+  const prevHost = globalThis.__flybot__
+  globalThis.__flybot__ = {
+    host: async (channel) => (channel === 'projects' ? { projects: [{ id: 'proj-atlas', name: 'Atlas' }] } : []),
+  }
+  try {
+    const settings = mount(client.WorkflowSettings, { call, roster: { bots: [] } })
+    await settle()
+    const picker = () => findAll(settings.tree, node => node.type === 'select' && node.props?.['aria-label'] === 'Project')[0]
+    assert.ok(picker(), 'the editor carries a Project picker')
+    assert.equal(picker().props.value, '', 'a workflow with no Project shows the unassigned choice')
+    assert.deepEqual(picker().children.map(textOf), ['Unassigned', 'Atlas'])
+
+    picker().props.onChange({ target: { value: 'proj-atlas' } })
+    await settle()
+    const bound = calls.filter(item => item.name === 'workflow/graph').at(-1)
+    assert.equal(bound.body.projectId, 'proj-atlas')
+    assert.equal(bound.body.workflowId, 'delivery')
+    assert.ok(Array.isArray(bound.body.nodes) && bound.body.nodes.length > 0, 'the save still carries the graph')
+    assert.equal(picker().props.value, 'proj-atlas', 'the picker repaints from the saved store')
+
+    picker().props.onChange({ target: { value: '' } })
+    await settle()
+    const cleared = calls.filter(item => item.name === 'workflow/graph').at(-1)
+    assert.equal(cleared.body.projectId, null, 'an empty choice clears the binding')
+    settings.unmount()
+  } finally {
+    globalThis.__flybot__ = prevHost
+  }
+})
diff --git a/plugins/workflow/test/save-graph-project.test.js b/plugins/workflow/test/save-graph-project.test.js
new file mode 100644
index 000000000..abdec0611
--- /dev/null
+++ b/plugins/workflow/test/save-graph-project.test.js
@@ -0,0 +1,51 @@
+// #1856: a workflow record carries `projectId`. The save is the only door that writes it, so it
+// is where the three cases are decided: an unknown Project refuses the save and writes nothing,
+// `null` clears the binding, and a save that omits the field keeps what is stored.
+import assert from 'node:assert/strict'
+import { test } from 'node:test'
+import { createWorkflowService } from '../src/service.js'
+
+const known = { 'project-1fe64499': { id: 'project-1fe64499', name: 'FlyBot 开发' } }
+
+function harness() {
+  return createWorkflowService({
+    persist: false,
+    now: () => 1_700_000_000_000,
+    bots: () => [{ id: 'bot-coder', name: 'Coder', role: '实现', remote: false }],
+    readProject: id => known[id] ?? null,
+  })
+}
+
+async function define(svc) {
+  const state = await svc.define({ name: 'ProjectProbe', nodes: [{ id: 'a', name: 'A', prompt: 'Do A.' }], edges: [] })
+  const item = state.workflows.find(workflow => workflow.name === 'ProjectProbe')
+  return { workflowId: item.id, nodes: item.nodes, edges: item.edges }
+}
+
+const stored = (svc, workflowId) => svc.state().workflows.find(workflow => workflow.id === workflowId)
+
+test('#1856: an unknown Project is refused and nothing is written', async () => {
+  const svc = harness()
+  const graph = await define(svc)
+  const saved = svc.saveGraph({ ...graph, projectId: 'project-missing' })
+  assert.equal(saved.ok, false, JSON.stringify(saved))
+  assert.match(String(saved.error), /Unknown Project project-missing/)
+  assert.equal(stored(svc, graph.workflowId).projectId ?? null, null, 'the record kept no binding')
+})
+
+test('#1856: projectId null clears the binding', async () => {
+  const svc = harness()
+  const graph = await define(svc)
+  assert.equal(svc.saveGraph({ ...graph, projectId: 'project-1fe64499' }).ok, true)
+  assert.equal(stored(svc, graph.workflowId).projectId, 'project-1fe64499')
+  assert.equal(svc.saveGraph({ ...graph, projectId: null }).ok, true)
+  assert.equal(stored(svc, graph.workflowId).projectId, null)
+})
+
+test('#1856: a save that omits projectId keeps the stored binding', async () => {
+  const svc = harness()
+  const graph = await define(svc)
+  assert.equal(svc.saveGraph({ ...graph, projectId: 'project-1fe64499' }).ok, true)
+  assert.equal(svc.saveGraph({ ...graph }).ok, true)
+  assert.equal(stored(svc, graph.workflowId).projectId, 'project-1fe64499')
+})