diff --git a/src/renderer/src/lib/agent-background-session-launch-host.ts b/src/renderer/src/lib/agent-background-session-launch-host.ts
new file mode 100644
index 00000000000..9ff199a5536
--- /dev/null
+++ b/src/renderer/src/lib/agent-background-session-launch-host.ts
@@ -0,0 +1,84 @@
+import type { useAppStore } from '@/store'
+import { getAgentLaunchPlatformForRepo } from '@/lib/agent-launch-platform'
+import { CLIENT_PLATFORM } from '@/lib/new-workspace'
+import { getLocalProjectExecutionRuntimeContext } from '@/lib/local-preflight-context'
+import { getFolderWorkspaceConnectionId } from '@/lib/folder-workspace-connection'
+import { parseWorkspaceKey } from '../../../shared/workspace-scope'
+import { isWindowsAbsolutePathLike } from '../../../shared/cross-platform-path'
+import { repoIsRemote } from '../../../shared/agent-launch-remote'
+
+type LaunchStore = ReturnType<typeof useAppStore.getState>
+type LaunchRepo = LaunchStore['repos'][number]
+
+export type AgentBackgroundLaunchHost = {
+  /** SSH connection to spawn on, or null for a local launch. */
+  connectionId: string | null
+  /** Platform whose shell quoting and CLI naming the startup plan must target. */
+  platform: NodeJS.Platform
+  isRemote: boolean
+  /**
+   * Connection the agent-status consumer should accept writes from. `undefined`
+   * means "unknown ownership, accept anything" — the pre-existing behavior for
+   * workspaces with no resolvable owner.
+   */
+  expectedConnectionId: string | null | undefined
+}
+
+/**
+ * SSH connection owning a folder-workspace selector, or null otherwise. Returns
+ * null when ownership is ambiguous (mixed local/remote children) so an unclear
+ * scope fails to a local launch rather than to the wrong host.
+ */
+function resolveFolderWorkspaceConnectionIdForLaunch(
+  store: LaunchStore,
+  worktreeId: string
+): string | null {
+  const parsed = parseWorkspaceKey(worktreeId)
+  if (parsed?.type !== 'folder') {
+    return null
+  }
+  return getFolderWorkspaceConnectionId(store, parsed.folderWorkspaceId) ?? null
+}
+
+/**
+ * Resolve which host an automation's agent session runs on.
+ *
+ * Why this is not just `repo.connectionId`: a folder workspace has no repo row —
+ * its synthetic repoId is `folder-workspace:<groupId>` — so repo-derived routing
+ * finds nothing and falls back to a LOCAL spawn using a path that exists only on
+ * the SSH host. Ownership has to come from the workspace scope, matching how
+ * ordinary terminal creation resolves it (#2989).
+ */
+export function resolveAgentBackgroundLaunchHost(args: {
+  store: LaunchStore
+  worktreeId: string
+  worktreePath: string | undefined
+  repo: LaunchRepo | null | undefined
+}): AgentBackgroundLaunchHost {
+  const { store, worktreeId, worktreePath, repo } = args
+  if (repo) {
+    return {
+      connectionId: repo.connectionId ?? null,
+      platform: getAgentLaunchPlatformForRepo(
+        repo,
+        repo.connectionId ? undefined : getLocalProjectExecutionRuntimeContext(store, worktreeId)
+      ),
+      isRemote: repoIsRemote(repo),
+      expectedConnectionId: repo.connectionId ?? null
+    }
+  }
+  const folderWorkspaceConnectionId = resolveFolderWorkspaceConnectionIdForLaunch(store, worktreeId)
+  return {
+    connectionId: folderWorkspaceConnectionId,
+    // A remote folder workspace runs under the host's own shell; only a
+    // Windows-style path marks a win32 host (same rule as the repo path above).
+    platform: folderWorkspaceConnectionId
+      ? isWindowsAbsolutePathLike(worktreePath ?? '')
+        ? 'win32'
+        : 'linux'
+      : CLIENT_PLATFORM,
+    isRemote: Boolean(folderWorkspaceConnectionId),
+    // A resolved folder-workspace connection is as authoritative as a repo's.
+    expectedConnectionId: folderWorkspaceConnectionId ?? undefined
+  }
+}
diff --git a/src/renderer/src/lib/agent-background-session-test-state.ts b/src/renderer/src/lib/agent-background-session-test-state.ts
index 37471e31b2c..85def0ffadb 100644
--- a/src/renderer/src/lib/agent-background-session-test-state.ts
+++ b/src/renderer/src/lib/agent-background-session-test-state.ts
@@ -24,7 +24,14 @@ export type AgentBackgroundSessionTestState = {
       | { kind: 'windows-host' }
       | { kind: 'wsl'; distro: string | null }
   }[]
-  repos: { id: string; connectionId: string | null; path: string }[]
+  repos: { id: string; connectionId: string | null; path: string; projectGroupId?: string | null }[]
+  folderWorkspaces: {
+    id: string
+    projectGroupId: string
+    folderPath: string
+    connectionId?: string | null
+  }[]
+  projectGroups: { id: string; parentGroupId?: string | null; connectionId?: string | null }[]
   worktreesByRepo: Record<
     string,
     { id: string; repoId: string; projectId: string; path: string; displayName: string }[]
@@ -88,6 +95,8 @@ export function createAgentBackgroundSessionTestState(mocks: {
         }
       ]
     },
+    folderWorkspaces: [] as AgentBackgroundSessionTestState['folderWorkspaces'],
+    projectGroups: [] as AgentBackgroundSessionTestState['projectGroups'],
     tabsByWorktree: { 'wt-1': [] as { id: string; title: string }[] },
     terminalLayoutsByTabId: {} as Record<
       string,
@@ -123,6 +132,8 @@ export function resetAgentBackgroundSessionTestState(state: AgentBackgroundSessi
   }
   state.projects = [{ id: 'repo-1', localWindowsRuntimePreference: { kind: 'inherit-global' } }]
   state.repos = [{ id: 'repo-1', connectionId: null, path: '/repo' }]
+  state.folderWorkspaces = []
+  state.projectGroups = []
   state.worktreesByRepo = {
     'repo-1': [
       {
diff --git a/src/renderer/src/lib/launch-agent-background-session-remote.test.ts b/src/renderer/src/lib/launch-agent-background-session-remote.test.ts
index 45b6a49e6df..a807baffa54 100644
--- a/src/renderer/src/lib/launch-agent-background-session-remote.test.ts
+++ b/src/renderer/src/lib/launch-agent-background-session-remote.test.ts
@@ -434,4 +434,54 @@ describe('launchAgentBackgroundSession remote runtime and SSH startup delivery',
     })
     expect(mockDispatchEvent).not.toHaveBeenCalled()
   })
+
+  it('spawns an SSH folder-workspace automation on the owning host, not locally', async () => {
+    // A folder workspace has no repo row — its synthetic repoId is
+    // `folder-workspace:<groupId>` — so repo-derived routing resolves no
+    // connection and spawns LOCALLY with a path that only exists on the remote
+    // host. Ownership must come from the workspace scope instead (#2989).
+    state.repos = [
+      { id: 'repo-1', connectionId: 'ssh-1', path: '/srv/proj/api', projectGroupId: 'grp-1' }
+    ]
+    state.projectGroups = [{ id: 'grp-1', parentGroupId: null, connectionId: 'ssh-1' }]
+    state.folderWorkspaces = [
+      { id: 'fw-1', projectGroupId: 'grp-1', folderPath: '/srv/proj', connectionId: 'ssh-1' }
+    ]
+    state.getKnownWorktreeById = (worktreeId: string) =>
+      worktreeId === 'folder:fw-1' ? { id: 'folder:fw-1', path: '/srv/proj' } : undefined
+    const { launchAgentBackgroundSession } = await import('./launch-agent-background-session')
+
+    await launchAgentBackgroundSession({
+      agent: 'claude',
+      worktreeId: 'folder:fw-1',
+      prompt: 'run the automation'
+    })
+
+    expect(mockSpawn).toHaveBeenCalledWith(
+      expect.objectContaining({ connectionId: 'ssh-1', cwd: '/srv/proj' })
+    )
+  })
+
+  it('keeps a local folder workspace on the local host', async () => {
+    state.repos = [
+      { id: 'repo-1', connectionId: null, path: '/home/me/proj/api', projectGroupId: 'grp-1' }
+    ]
+    state.projectGroups = [{ id: 'grp-1', parentGroupId: null, connectionId: null }]
+    state.folderWorkspaces = [
+      { id: 'fw-1', projectGroupId: 'grp-1', folderPath: '/home/me/proj', connectionId: null }
+    ]
+    state.getKnownWorktreeById = (worktreeId: string) =>
+      worktreeId === 'folder:fw-1' ? { id: 'folder:fw-1', path: '/home/me/proj' } : undefined
+    const { launchAgentBackgroundSession } = await import('./launch-agent-background-session')
+
+    await launchAgentBackgroundSession({
+      agent: 'claude',
+      worktreeId: 'folder:fw-1',
+      prompt: 'run the automation'
+    })
+
+    expect(mockSpawn).toHaveBeenCalledWith(
+      expect.objectContaining({ connectionId: null, cwd: '/home/me/proj' })
+    )
+  })
 })
diff --git a/src/renderer/src/lib/launch-agent-background-session.ts b/src/renderer/src/lib/launch-agent-background-session.ts
index a9c5bab276c..0c33865b580 100644
--- a/src/renderer/src/lib/launch-agent-background-session.ts
+++ b/src/renderer/src/lib/launch-agent-background-session.ts
@@ -4,18 +4,15 @@ import type {
   LaunchAgentBackgroundSessionArgs,
   LaunchAgentBackgroundSessionResult
 } from '@/lib/agent-background-session-contract'
-import { getAgentLaunchPlatformForRepo } from '@/lib/agent-launch-platform'
-import { CLIENT_PLATFORM } from '@/lib/new-workspace'
 import { tuiAgentToAgentKind } from '@/lib/telemetry'
 import { scheduleAgentBackgroundDraft } from '@/lib/agent-background-draft-delivery'
-import { getLocalProjectExecutionRuntimeContext } from '@/lib/local-preflight-context'
 import { requestBackgroundTerminalWorktreeMount } from '@/components/terminal/background-terminal-worktree-mount'
 import {
   resolveTuiAgentLaunchArgs,
   resolveTuiAgentLaunchEnv
 } from '../../../shared/tui-agent-launch-defaults'
 import { TUI_AGENT_CONFIG } from '../../../shared/tui-agent-config'
-import { repoIsRemote } from '../../../shared/agent-launch-remote'
+import { resolveAgentBackgroundLaunchHost } from '@/lib/agent-background-session-launch-host'
 import { makePaneKey } from '../../../shared/stable-pane-id'
 import {
   registerEagerPtyBuffer,
@@ -69,15 +66,16 @@ export async function launchAgentBackgroundSession(
   const cmdOverrides = store.settings?.agentCmdOverrides ?? {}
   const agentArgs = resolveTuiAgentLaunchArgs(agent, store.settings?.agentDefaultArgs)
   const agentEnv = resolveTuiAgentLaunchEnv(agent, store.settings?.agentDefaultEnv)
-  const launchPlatform = repo
-    ? getAgentLaunchPlatformForRepo(
-        repo,
-        repo.connectionId ? undefined : getLocalProjectExecutionRuntimeContext(store, worktreeId)
-      )
-    : CLIENT_PLATFORM
   // Why: SSH remotes deploy the CLI shim as plain `orca`, so the Linux-only
-  // `orca-ide` rename must not be applied for remote launches.
-  const isRemote = repo ? repoIsRemote(repo) : false
+  // `orca-ide` rename must not be applied for remote launches. Folder workspaces
+  // have no repo row, so host resolution cannot go through `repo` alone (#2989).
+  const launchHost = resolveAgentBackgroundLaunchHost({
+    store,
+    worktreeId,
+    worktreePath: worktree.path,
+    repo
+  })
+  const { platform: launchPlatform, isRemote } = launchHost
   const startupShell = resolveLocalWindowsAgentStartupShell({
     platform: launchPlatform,
     isRemote,
@@ -115,7 +113,7 @@ export async function launchAgentBackgroundSession(
       env: startupPlan.env
     })
   let paneKey = makePaneKey(reservedTabId, leafId)
-  const sshConnectionId = repo?.connectionId ?? null
+  const sshConnectionId = launchHost.connectionId
   const sshStartupDelivery = createSshBackgroundStartupDelivery({
     command: sshConnectionId ? startupPlan.launchCommand : null,
     waitForShellReady:
@@ -163,7 +161,7 @@ export async function launchAgentBackgroundSession(
     paneKey,
     launchToken,
     mainOwnsAgentStatusWrites,
-    expectedConnectionId: repo ? (repo.connectionId ?? null) : undefined,
+    expectedConnectionId: launchHost.expectedConnectionId,
     runtimeEnvironmentId: runtimeTarget.kind === 'environment' ? runtimeTarget.environmentId : null,
     getPtyId: () => ptyId,
     onAgentStatus