diff --git a/docs/data-model.md b/docs/data-model.md
index 71e68c7bd..a9d89ae4f 100644
--- a/docs/data-model.md
+++ b/docs/data-model.md
@@ -410,6 +410,11 @@ Array of workspace records. A workspace is a specific working directory within a
 
 > **Opaque-ID invariant:** `workspaceId` is opaque identity, never a filesystem path. Filesystem and git operations take `cwd`/`workspaceDirectory` only — never the id. Path-derived grouping keys (e.g. `deriveWorkspaceDirectoryKey`, used at bootstrap to group agents into a workspace) are directory keys, not workspace identity, and must not be persisted or compared as ids.
 
+`projectId` is still a real FK: workspace records should have a matching project record. Read-only
+history surfaces tolerate transient orphaned workspaces by omitting those rows so one bad FK cannot
+blank the whole History screen, but mutation paths should repair or remove the orphaned state rather
+than treating it as valid.
+
 ---
 
 ## 8. Push Token Store
diff --git a/packages/app/e2e/empty-project-persists.spec.ts b/packages/app/e2e/empty-project-persists.spec.ts
index 48972483d..2c8443c22 100644
--- a/packages/app/e2e/empty-project-persists.spec.ts
+++ b/packages/app/e2e/empty-project-persists.spec.ts
@@ -27,6 +27,24 @@ async function hideWorkspaceFromSidebar(page: Page, workspaceId: string): Promis
   await archiveItem.click();
 }
 
+async function removeProjectFromSidebar(page: Page, projectId: string): Promise<void> {
+  const projectRow = page.getByTestId(`sidebar-project-row-${projectId}`);
+  await expect(projectRow).toBeVisible({ timeout: 30_000 });
+  await projectRow.hover();
+
+  const kebab = page.getByTestId(`sidebar-project-kebab-${projectId}`);
+  await expect(kebab).toBeVisible({ timeout: 10_000 });
+  await kebab.click();
+
+  // Removing a project raises a browser confirm; accept it so the
+  // user-confirmed removal proceeds deterministically.
+  page.once("dialog", (dialog) => void dialog.accept());
+
+  const removeItem = page.getByTestId(`sidebar-project-menu-remove-${projectId}`);
+  await expect(removeItem).toBeVisible({ timeout: 10_000 });
+  await removeItem.click();
+}
+
 // Model B makes the project a first-class parent: archiving its last workspace
 // must not delete the project. The per-project "+ New workspace" row is gone;
 // the empty project keeps its parent row, and creation stays reachable from the
@@ -76,3 +94,43 @@ test.describe("Empty project persists", () => {
     }
   });
 });
+
+test.describe("Project remove", () => {
+  test("removing a project from project actions removes it from the sidebar", async ({ page }) => {
+    const workspace = await seedWorkspace({ repoPrefix: "project-remove-sidebar-" });
+
+    try {
+      const projectRow = page.getByTestId(`sidebar-project-row-${workspace.projectId}`);
+
+      await gotoAppShell(page);
+      await waitForSidebarHydration(page);
+      await expect(projectRow).toBeVisible({ timeout: 30_000 });
+      await expect(page.getByTestId(workspaceRowTestId(workspace.workspaceId))).toBeVisible({
+        timeout: 30_000,
+      });
+
+      await removeProjectFromSidebar(page, workspace.projectId);
+
+      await expect(page.getByTestId(workspaceRowTestId(workspace.workspaceId))).toHaveCount(0, {
+        timeout: 30_000,
+      });
+      await expect(projectRow).toHaveCount(0, { timeout: 30_000 });
+
+      await page.reload();
+      await waitForSidebarHydration(page);
+      await expect(projectRow).toHaveCount(0, { timeout: 30_000 });
+
+      const reopened = await workspace.client.openProject(workspace.repoPath);
+      expect(reopened.error).toBeNull();
+      expect(reopened.workspace?.projectDisplayName).toBe(workspace.projectDisplayName);
+
+      await page.reload();
+      await waitForSidebarHydration(page);
+      await expect(projectRow).toBeVisible({ timeout: 30_000 });
+      await expect(projectRow).toContainText(workspace.projectDisplayName);
+      await expect(projectRow).not.toContainText(workspace.repoPath);
+    } finally {
+      await workspace.cleanup();
+    }
+  });
+});
diff --git a/packages/app/src/components/sidebar-workspace-list.tsx b/packages/app/src/components/sidebar-workspace-list.tsx
index 8467117c4..131b81e57 100644
--- a/packages/app/src/components/sidebar-workspace-list.tsx
+++ b/packages/app/src/components/sidebar-workspace-list.tsx
@@ -69,6 +69,7 @@ import {
   type SidebarWorkspaceEntry,
 } from "@/hooks/use-sidebar-workspaces-list";
 import { useSidebarOrderStore } from "@/stores/sidebar-order-store";
+import { useSessionStore } from "@/stores/session-store";
 import { useShowShortcutBadges } from "@/hooks/use-show-shortcut-badges";
 import { ContextMenuTrigger, useContextMenu } from "@/components/ui/context-menu";
 import {
@@ -113,8 +114,6 @@ import { buildSidebarProjectRowModel } from "@/utils/sidebar-project-row-model";
 import { redirectIfArchivingActiveWorkspace } from "@/utils/sidebar-workspace-archive-redirect";
 import { openExternalUrl } from "@/utils/open-external-url";
 import { requireWorkspaceDirectory, resolveWorkspaceDirectory } from "@/utils/workspace-directory";
-import { archiveWorkspacesOptimistically } from "@/workspace/workspace-archive";
-import { selectProjectWorkspacesToArchive } from "@/workspace/project-workspace-archive";
 import { useWorkspaceArchive } from "@/workspace/use-workspace-archive";
 import {
   isWeb as platformIsWeb,
@@ -1785,6 +1784,7 @@ function ProjectBlock({
   displayName,
   iconDataUri,
   serverId,
+  canRemoveProject,
   selectionEnabled,
   showShortcutBadges,
   shortcutIndexByWorkspaceKey,
@@ -1805,6 +1805,7 @@ function ProjectBlock({
   displayName: string;
   iconDataUri: string | null;
   serverId: string | null;
+  canRemoveProject: boolean;
   selectionEnabled: boolean;
   showShortcutBadges: boolean;
   shortcutIndexByWorkspaceKey: Map<string, number>;
@@ -1923,26 +1924,24 @@ function ProjectBlock({
         toast.error(t("sidebar.project.toasts.hostDisconnected"));
         return;
       }
+      if (!canRemoveProject) {
+        toast.error(t("sidebar.project.toasts.updateHostToRemove"));
+        return;
+      }
 
       setIsRemovingProject(true);
-      void selectProjectWorkspacesToArchive(project.workspaces)
-        .then((workspaces) => archiveWorkspacesOptimistically({ client, workspaces }))
-        .then((failures) => {
-          if (failures.length > 0) {
-            toast.error(t("sidebar.project.toasts.removeFailed"));
-          }
-          setIsRemovingProject(false);
-          return;
-        })
+      void client
+        .removeProject(project.projectKey)
         .catch((error) => {
           toast.error(
             error instanceof Error ? error.message : t("sidebar.project.toasts.removeFailed"),
           );
+        })
+        .finally(() => {
           setIsRemovingProject(false);
-          return;
         });
     })();
-  }, [isRemovingProject, serverId, displayName, t, toast, project.workspaces]);
+  }, [isRemovingProject, serverId, displayName, t, toast, project.projectKey, canRemoveProject]);
 
   const handleToggleCollapsed = useCallback(() => {
     onToggleCollapsed(project.projectKey);
@@ -2000,6 +1999,7 @@ function areProjectBlockPropsEqual(previous: ProjectBlockProps, next: ProjectBlo
     previous.displayName === next.displayName &&
     previous.iconDataUri === next.iconDataUri &&
     previous.serverId === next.serverId &&
+    previous.canRemoveProject === next.canRemoveProject &&
     previous.selectionEnabled === next.selectionEnabled &&
     previous.showShortcutBadges === next.showShortcutBadges &&
     previous.shortcutIndexByWorkspaceKey === next.shortcutIndexByWorkspaceKey &&
@@ -2145,6 +2145,9 @@ function ProjectModeList({
   const setProjectOrder = useSidebarOrderStore((state) => state.setProjectOrder);
   const getWorkspaceOrder = useSidebarOrderStore((state) => state.getWorkspaceOrder);
   const setWorkspaceOrder = useSidebarOrderStore((state) => state.setWorkspaceOrder);
+  const canRemoveProject = useSessionStore((state) =>
+    serverId ? state.sessions[serverId]?.serverInfo?.features?.projectRemove === true : false,
+  );
 
   const isWorkspaceRoute = useMemo(
     () => Boolean(pathname && parseHostWorkspaceRouteFromPathname(pathname)),
@@ -2309,6 +2312,7 @@ function ProjectModeList({
           displayName={item.projectName}
           iconDataUri={projectIconByProjectKey.get(item.projectKey) ?? null}
           serverId={serverId}
+          canRemoveProject={canRemoveProject}
           selectionEnabled={selectionEnabled}
           showShortcutBadges={showShortcutBadges}
           shortcutIndexByWorkspaceKey={shortcutIndexByWorkspaceKey}
@@ -2335,6 +2339,7 @@ function ProjectModeList({
       onToggleProjectCollapsed,
       parentGestureRef,
       projectIconByProjectKey,
+      canRemoveProject,
       selectionEnabled,
       serverId,
       shortcutIndexByWorkspaceKey,
diff --git a/packages/app/src/contexts/session-context.tsx b/packages/app/src/contexts/session-context.tsx
index 5d9f0199f..750a1e6bf 100644
--- a/packages/app/src/contexts/session-context.tsx
+++ b/packages/app/src/contexts/session-context.tsx
@@ -531,6 +531,7 @@ function SessionProviderInternal({ children, serverId, client }: SessionProvider
   const setWorkspaces = useSessionStore((state) => state.setWorkspaces);
   const setEmptyProjects = useSessionStore((state) => state.setEmptyProjects);
   const addEmptyProject = useSessionStore((state) => state.addEmptyProject);
+  const removeEmptyProject = useSessionStore((state) => state.removeEmptyProject);
   const mergeWorkspaces = useSessionStore((state) => state.mergeWorkspaces);
   const removeWorkspace = useSessionStore((state) => state.removeWorkspace);
   const setAgentLastActivity = useSessionStore((state) => state.setAgentLastActivity);
@@ -1348,6 +1349,9 @@ function SessionProviderInternal({ children, serverId, client }: SessionProvider
         if (message.payload.emptyProject) {
           addEmptyProject(serverId, normalizeEmptyProjectDescriptor(message.payload.emptyProject));
         }
+        if (message.payload.removedProjectId) {
+          removeEmptyProject(serverId, message.payload.removedProjectId);
+        }
         return;
       }
       const workspace = normalizeWorkspaceDescriptor(message.payload.workspace);
@@ -1771,6 +1775,7 @@ function SessionProviderInternal({ children, serverId, client }: SessionProvider
     removeWorkspace,
     removeWorkspaceSetup,
     addEmptyProject,
+    removeEmptyProject,
     setAgentLastActivity,
     setPendingPermissions,
     setHasHydratedAgents,
diff --git a/packages/app/src/i18n/resources.test.ts b/packages/app/src/i18n/resources.test.ts
index 04e194dfb..42a56a4dc 100644
--- a/packages/app/src/i18n/resources.test.ts
+++ b/packages/app/src/i18n/resources.test.ts
@@ -249,6 +249,9 @@ describe("translation resources", () => {
   it("includes sidebar and workspace creation keys for the Batch 4C migration", () => {
     expect(en.sidebar.workspace.actions.copyPath).toBe("Copy path");
     expect(en.sidebar.project.confirmations.removeTitle).toBe("Remove project?");
+    expect(en.sidebar.project.toasts.updateHostToRemove).toBe(
+      "Update the host to remove projects.",
+    );
     expect(en.newWorkspace.title).toBe("New workspace");
     expect(en.newWorkspace.refPicker.searchPlaceholder).toBe("Search branches and PRs");
     expect(en.openProject.tiles.addProject.title).toBe("Add a project");
diff --git a/packages/app/src/i18n/resources/ar.ts b/packages/app/src/i18n/resources/ar.ts
index ac47466a6..d82735eda 100644
--- a/packages/app/src/i18n/resources/ar.ts
+++ b/packages/app/src/i18n/resources/ar.ts
@@ -787,6 +787,7 @@ export const ar: TranslationResources = {
       toasts: {
         hostDisconnected: "Host غير متصل",
         removeFailed: "فشل في إزالة بعض مساحات العمل",
+        updateHostToRemove: "قم بتحديث Host لإزالة المشاريع.",
       },
       empty: {
         title: "لا توجد مشاريع حتى الآن",
diff --git a/packages/app/src/i18n/resources/en.ts b/packages/app/src/i18n/resources/en.ts
index 7812d65b9..15822fd65 100644
--- a/packages/app/src/i18n/resources/en.ts
+++ b/packages/app/src/i18n/resources/en.ts
@@ -794,6 +794,7 @@ export const en = {
       toasts: {
         hostDisconnected: "Host is not connected",
         removeFailed: "Failed to remove some workspaces",
+        updateHostToRemove: "Update the host to remove projects.",
       },
       empty: {
         title: "No projects yet",
diff --git a/packages/app/src/i18n/resources/es.ts b/packages/app/src/i18n/resources/es.ts
index 53a1094f1..963e8b6fe 100644
--- a/packages/app/src/i18n/resources/es.ts
+++ b/packages/app/src/i18n/resources/es.ts
@@ -814,6 +814,7 @@ export const es: TranslationResources = {
       toasts: {
         hostDisconnected: "Hostno está conectado",
         removeFailed: "No se pudieron eliminar algunos espacios de trabajo",
+        updateHostToRemove: "Actualiza el host para eliminar proyectos.",
       },
       empty: {
         title: "Aún no hay proyectos",
diff --git a/packages/app/src/i18n/resources/fr.ts b/packages/app/src/i18n/resources/fr.ts
index a794a8360..fe5fcacd4 100644
--- a/packages/app/src/i18n/resources/fr.ts
+++ b/packages/app/src/i18n/resources/fr.ts
@@ -813,6 +813,7 @@ export const fr: TranslationResources = {
       toasts: {
         hostDisconnected: "Hostn'est pas connecté",
         removeFailed: "Échec de la suppression de certains espaces de travail",
+        updateHostToRemove: "Mettez à jour le host pour supprimer des projets.",
       },
       empty: {
         title: "Aucun projet pour l'instant",
diff --git a/packages/app/src/i18n/resources/ru.ts b/packages/app/src/i18n/resources/ru.ts
index fc6c837a4..a17d1a597 100644
--- a/packages/app/src/i18n/resources/ru.ts
+++ b/packages/app/src/i18n/resources/ru.ts
@@ -806,6 +806,7 @@ export const ru: TranslationResources = {
       toasts: {
         hostDisconnected: "Host не подключен",
         removeFailed: "Не удалось удалить некоторые рабочие области.",
+        updateHostToRemove: "Обновите host, чтобы удалять проекты.",
       },
       empty: {
         title: "Пока нет проектов",
diff --git a/packages/app/src/i18n/resources/zh-CN.ts b/packages/app/src/i18n/resources/zh-CN.ts
index bf28983e8..3a88db254 100644
--- a/packages/app/src/i18n/resources/zh-CN.ts
+++ b/packages/app/src/i18n/resources/zh-CN.ts
@@ -779,6 +779,7 @@ export const zhCN: TranslationResources = {
       toasts: {
         hostDisconnected: "Host 未连接",
         removeFailed: "部分 workspace 移除失败",
+        updateHostToRemove: "更新 host 以移除 projects。",
       },
       empty: {
         title: "还没有 projects",
diff --git a/packages/app/src/stores/session-store.test.ts b/packages/app/src/stores/session-store.test.ts
index 7e7f78d32..9d1491fde 100644
--- a/packages/app/src/stores/session-store.test.ts
+++ b/packages/app/src/stores/session-store.test.ts
@@ -48,6 +48,7 @@ function getTestSessionReferences() {
     sessions: state.sessions,
     session,
     workspaces: session.workspaces,
+    emptyProjects: session.emptyProjects,
   };
 }
 
@@ -448,6 +449,48 @@ describe("removeWorkspace", () => {
   });
 });
 
+describe("removeEmptyProject", () => {
+  it("removes an empty project by project id", () => {
+    const store = useSessionStore.getState();
+    initializeTestSession();
+    store.setEmptyProjects("test-server", [
+      {
+        projectId: "project-empty",
+        projectDisplayName: "Empty",
+        projectCustomName: null,
+        projectRootPath: "/repo/empty",
+        projectKind: "git",
+      },
+    ]);
+
+    store.removeEmptyProject("test-server", "project-empty");
+
+    expect(getTestSessionReferences().emptyProjects.has("project-empty")).toBe(false);
+  });
+
+  it("preserves identity when removing a missing empty project", () => {
+    const store = useSessionStore.getState();
+    initializeTestSession();
+    store.setEmptyProjects("test-server", [
+      {
+        projectId: "project-empty",
+        projectDisplayName: "Empty",
+        projectCustomName: null,
+        projectRootPath: "/repo/empty",
+        projectKind: "git",
+      },
+    ]);
+    const before = getTestSessionReferences();
+
+    store.removeEmptyProject("test-server", "project-missing");
+    const after = getTestSessionReferences();
+
+    expect(after.sessions).toBe(before.sessions);
+    expect(after.session).toBe(before.session);
+    expect(after.emptyProjects).toBe(before.emptyProjects);
+  });
+});
+
 describe("patchWorkspaceScripts", () => {
   it("preserves workspace entry identity when scripts are content-equal", () => {
     const script = {
diff --git a/packages/app/src/stores/session-store.ts b/packages/app/src/stores/session-store.ts
index 5e5e00cdb..88f11ae4a 100644
--- a/packages/app/src/stores/session-store.ts
+++ b/packages/app/src/stores/session-store.ts
@@ -460,6 +460,7 @@ interface SessionStoreActions {
   removeWorkspace: (serverId: string, workspaceId: string) => void;
   setEmptyProjects: (serverId: string, emptyProjects: Iterable<EmptyProjectDescriptor>) => void;
   addEmptyProject: (serverId: string, emptyProject: EmptyProjectDescriptor) => void;
+  removeEmptyProject: (serverId: string, projectId: string) => void;
   setWorkspaceRestoreStatus: (
     serverId: string,
     workspaceId: string,
@@ -1265,6 +1266,24 @@ export const useSessionStore = create<SessionStore>()(
         });
       },
 
+      removeEmptyProject: (serverId, projectId) => {
+        set((prev) => {
+          const session = prev.sessions[serverId];
+          if (!session?.emptyProjects.has(projectId)) {
+            return prev;
+          }
+          const next = new Map(session.emptyProjects);
+          next.delete(projectId);
+          return {
+            ...prev,
+            sessions: {
+              ...prev.sessions,
+              [serverId]: { ...session, emptyProjects: next },
+            },
+          };
+        });
+      },
+
       setWorkspaceRestoreStatus: (serverId, workspaceId, status) => {
         set((prev) => {
           const session = prev.sessions[serverId];
diff --git a/packages/client/src/daemon-client.test.ts b/packages/client/src/daemon-client.test.ts
index 8bae233f3..36dfdf3d0 100644
--- a/packages/client/src/daemon-client.test.ts
+++ b/packages/client/src/daemon-client.test.ts
@@ -1521,6 +1521,47 @@ test("sends first-agent prompt context with workspace.create.request", async ()
   });
 });
 
+test("sends project.remove.request", async () => {
+  const logger = createMockLogger();
+  const mock = createMockTransport();
+
+  const client = new DaemonClient({
+    url: "ws://test",
+    clientId: "clsk_unit_test",
+    logger,
+    reconnect: { enabled: false },
+    transportFactory: () => mock.transport,
+  });
+  clients.push(client);
+
+  const connectPromise = client.connect();
+  mock.triggerOpen();
+  await connectPromise;
+
+  const removePromise = client.removeProject("remote:github.com/acme/app", "req-remove-project");
+
+  expect(parseSentFrame(mock.sent[0])).toEqual({
+    type: "project.remove.request",
+    requestId: "req-remove-project",
+    projectId: "remote:github.com/acme/app",
+  });
+
+  mock.triggerMessage(
+    wrapSessionMessage({
+      type: "project.remove.response",
+      payload: {
+        requestId: "req-remove-project",
+        projectId: "remote:github.com/acme/app",
+        accepted: true,
+        removedWorkspaceIds: ["ws-main"],
+        error: null,
+      },
+    }),
+  );
+
+  await expect(removePromise).resolves.toEqual({ removedWorkspaceIds: ["ws-main"] });
+});
+
 test("sends worktree base-ref fields in create_paseo_worktree_request", async () => {
   const logger = createMockLogger();
   const mock = createMockTransport();
diff --git a/packages/client/src/daemon-client.ts b/packages/client/src/daemon-client.ts
index e8507b6c7..776644d1e 100644
--- a/packages/client/src/daemon-client.ts
+++ b/packages/client/src/daemon-client.ts
@@ -2153,6 +2153,24 @@ export class DaemonClient {
     return { customName: payload.customName };
   }
 
+  async removeProject(
+    projectId: string,
+    requestId?: string,
+  ): Promise<{ removedWorkspaceIds: string[] }> {
+    const payload = await this.sendNamespacedCorrelatedSessionRequest<"project.remove.response">({
+      requestId,
+      message: {
+        type: "project.remove.request",
+        projectId,
+      },
+      timeout: 10000,
+    });
+    if (!payload.accepted) {
+      throw new Error(payload.error ?? "removeProject rejected");
+    }
+    return { removedWorkspaceIds: payload.removedWorkspaceIds };
+  }
+
   async setWorkspaceTitle(
     workspaceId: string,
     title: string | null,
diff --git a/packages/protocol/src/messages.checkout-pr-schema.test.ts b/packages/protocol/src/messages.checkout-pr-schema.test.ts
index 38714d914..1395bb356 100644
--- a/packages/protocol/src/messages.checkout-pr-schema.test.ts
+++ b/packages/protocol/src/messages.checkout-pr-schema.test.ts
@@ -340,4 +340,18 @@ describe("checkout PR schemas", () => {
       githubCheckDetails: true,
     });
   });
+
+  test("accepts the project removal server_info feature flag", () => {
+    expect(
+      ServerInfoStatusPayloadSchema.parse({
+        status: "server_info",
+        serverId: "srv_test",
+        features: {
+          projectRemove: true,
+        },
+      }).features,
+    ).toEqual({
+      projectRemove: true,
+    });
+  });
 });
diff --git a/packages/protocol/src/messages.ts b/packages/protocol/src/messages.ts
index 652d572bb..358a4c055 100644
--- a/packages/protocol/src/messages.ts
+++ b/packages/protocol/src/messages.ts
@@ -795,6 +795,12 @@ export const ProjectRenameRequestSchema = z.object({
   requestId: z.string(),
 });
 
+export const ProjectRemoveRequestSchema = z.object({
+  type: z.literal("project.remove.request"),
+  projectId: z.string(),
+  requestId: z.string(),
+});
+
 export const WorkspaceTitleSetRequestSchema = z.object({
   type: z.literal("workspace.title.set.request"),
   workspaceId: z.string(),
@@ -1340,6 +1346,19 @@ export const ProjectRenameResponseSchema = z.object({
   payload: ProjectRenameResponsePayloadSchema,
 });
 
+export const ProjectRemoveResponsePayloadSchema = z.object({
+  requestId: z.string(),
+  projectId: z.string(),
+  accepted: z.boolean(),
+  removedWorkspaceIds: z.array(z.string()).default([]),
+  error: z.string().nullable(),
+});
+
+export const ProjectRemoveResponseSchema = z.object({
+  type: z.literal("project.remove.response"),
+  payload: ProjectRemoveResponsePayloadSchema,
+});
+
 export const WorkspaceTitleSetResponsePayloadSchema = z.object({
   requestId: z.string(),
   workspaceId: z.string(),
@@ -1968,6 +1987,7 @@ export const SessionInboundMessageSchema = z.discriminatedUnion("type", [
   CloseItemsRequestMessageSchema,
   UpdateAgentRequestMessageSchema,
   ProjectRenameRequestSchema,
+  ProjectRemoveRequestSchema,
   WorkspaceTitleSetRequestSchema,
   SetVoiceModeMessageSchema,
   SendAgentMessageRequestSchema,
@@ -2256,6 +2276,8 @@ export const ServerInfoStatusPayloadSchema = z
         checkoutRefresh: z.boolean().optional(),
         // COMPAT(workspaceMultiplicity): added in v0.1.97, drop the gate when floor >= v0.1.97
         workspaceMultiplicity: z.boolean().optional(),
+        // COMPAT(projectRemove): added in v0.1.97, drop the gate when floor >= v0.1.97.
+        projectRemove: z.boolean().optional(),
         // COMPAT(worktreeRestore): added in v0.1.98, drop the gate when floor >= v0.1.98
         worktreeRestore: z.boolean().optional(),
       })
@@ -2692,6 +2714,9 @@ export const WorkspaceUpdateMessageSchema = z.object({
       // daemons omit it; old clients ignore it and surface the empty project on
       // their next workspace fetch instead.
       emptyProject: WorkspaceProjectDescriptorPayloadSchema.optional(),
+      // Project removal is represented on the existing workspace update channel
+      // so old clients can still parse the message and ignore the extra field.
+      removedProjectId: z.string().optional(),
     }),
   ]),
 });
@@ -3997,6 +4022,7 @@ export const SessionOutboundMessageSchema = z.discriminatedUnion("type", [
   AgentRewindResponseMessageSchema,
   UpdateAgentResponseMessageSchema,
   ProjectRenameResponseSchema,
+  ProjectRemoveResponseSchema,
   WorkspaceTitleSetResponseSchema,
   WaitForFinishResponseMessageSchema,
   AgentPermissionRequestMessageSchema,
@@ -4143,6 +4169,7 @@ export type SetAgentFeatureResponseMessage = z.infer<typeof SetAgentFeatureRespo
 export type AgentRewindResponseMessage = z.infer<typeof AgentRewindResponseMessageSchema>;
 export type UpdateAgentResponseMessage = z.infer<typeof UpdateAgentResponseMessageSchema>;
 export type ProjectRenameResponse = z.infer<typeof ProjectRenameResponseSchema>;
+export type ProjectRemoveResponse = z.infer<typeof ProjectRemoveResponseSchema>;
 export type WorkspaceTitleSetResponse = z.infer<typeof WorkspaceTitleSetResponseSchema>;
 export type WorkspaceTitleSetResponsePayload = z.infer<
   typeof WorkspaceTitleSetResponsePayloadSchema
@@ -4150,6 +4177,7 @@ export type WorkspaceTitleSetResponsePayload = z.infer<
 export type WorkspaceCreateRequest = z.infer<typeof WorkspaceCreateRequestSchema>;
 export type WorkspaceCreateResponse = z.infer<typeof WorkspaceCreateResponseSchema>;
 export type ProjectRenameResponsePayload = z.infer<typeof ProjectRenameResponsePayloadSchema>;
+export type ProjectRemoveResponsePayload = z.infer<typeof ProjectRemoveResponsePayloadSchema>;
 export type WaitForFinishResponseMessage = z.infer<typeof WaitForFinishResponseMessageSchema>;
 export type AgentPermissionRequestMessage = z.infer<typeof AgentPermissionRequestMessageSchema>;
 export type AgentPermissionResolvedMessage = z.infer<typeof AgentPermissionResolvedMessageSchema>;
@@ -4265,6 +4293,7 @@ export type ResumeAgentRequestMessage = z.infer<typeof ResumeAgentRequestMessage
 export type DeleteAgentRequestMessage = z.infer<typeof DeleteAgentRequestMessageSchema>;
 export type UpdateAgentRequestMessage = z.infer<typeof UpdateAgentRequestMessageSchema>;
 export type ProjectRenameRequest = z.infer<typeof ProjectRenameRequestSchema>;
+export type ProjectRemoveRequest = z.infer<typeof ProjectRemoveRequestSchema>;
 export type WorkspaceTitleSetRequest = z.infer<typeof WorkspaceTitleSetRequestSchema>;
 export type SetAgentModeRequestMessage = z.infer<typeof SetAgentModeRequestMessageSchema>;
 export type SetAgentModelRequestMessage = z.infer<typeof SetAgentModelRequestMessageSchema>;
diff --git a/packages/server/src/server/session.ts b/packages/server/src/server/session.ts
index ff316a4a2..47427dd67 100644
--- a/packages/server/src/server/session.ts
+++ b/packages/server/src/server/session.ts
@@ -197,7 +197,10 @@ import {
   type ProjectConfigRpcError,
 } from "../utils/paseo-config-file.js";
 import { buildMetadataPrompt } from "../utils/build-metadata-prompt.js";
-import { archivePersistedWorkspaceRecord } from "./workspace-archive-service.js";
+import {
+  archivePersistedWorkspaceRecord,
+  archiveWorkspaceContents,
+} from "./workspace-archive-service.js";
 import { WorkspaceReconciliationService } from "./workspace-reconciliation-service.js";
 import type { ServiceProxySubsystem } from "./service-proxy.js";
 import {
@@ -1703,6 +1706,17 @@ export class Session {
     return this.buildProjectPlacementForWorkspace(workspace);
   }
 
+  private async buildProjectPlacementForExistingWorkspaceProject(
+    workspaceId: string,
+  ): Promise<ProjectPlacementPayload | null> {
+    const workspace = await this.workspaceRegistry.get(workspaceId);
+    if (!workspace) return null;
+
+    const project = await this.projectRegistry.get(workspace.projectId);
+    if (!project) return null;
+    return this.buildProjectPlacementForWorkspace(workspace, project);
+  }
+
   private async forwardAgentUpdate(agent: ManagedAgent): Promise<void> {
     try {
       const subscription = this.agentUpdatesSubscription;
@@ -2184,6 +2198,8 @@ export class Session {
         return this.handleOpenProjectRequest(msg);
       case "archive_workspace_request":
         return this.handleArchiveWorkspaceRequest(msg);
+      case "project.remove.request":
+        return this.handleProjectRemoveRequest(msg);
       case "workspace.create.request":
         return this.handleWorkspaceCreateRequest(msg);
       case "workspace.clear_attention.request":
@@ -2685,6 +2701,97 @@ export class Session {
     }
   }
 
+  private async handleProjectRemoveRequest(
+    request: Extract<SessionInboundMessage, { type: "project.remove.request" }>,
+  ): Promise<void> {
+    const { projectId, requestId } = request;
+    this.sessionLogger.info({ projectId, requestId }, "session: project.remove.request");
+
+    try {
+      const projectWorkspaces = (await this.workspaceRegistry.list()).filter(
+        (workspace) => workspace.projectId === projectId,
+      );
+      const activeWorkspaceIds = projectWorkspaces
+        .filter((workspace) => !workspace.archivedAt)
+        .map((workspace) => workspace.workspaceId);
+
+      if (activeWorkspaceIds.length > 0) {
+        this.markWorkspaceArchiving(activeWorkspaceIds, new Date().toISOString());
+        await this.emitWorkspaceUpdatesForWorkspaceIds(activeWorkspaceIds, {
+          skipReconcile: true,
+        });
+      }
+
+      const removedWorkspaceIds: string[] = [];
+      try {
+        for (const workspaceId of activeWorkspaceIds) {
+          await archiveWorkspaceContents(
+            {
+              agentManager: this.agentManager,
+              agentStorage: this.agentStorage,
+              killTerminalsForWorkspace: (id) =>
+                this.terminalController.killTerminalsForWorkspace(id),
+              sessionLogger: this.sessionLogger,
+            },
+            workspaceId,
+          );
+          await this.archiveWorkspaceRecord(workspaceId);
+          removedWorkspaceIds.push(workspaceId);
+        }
+
+        await this.projectRegistry.remove(projectId);
+      } finally {
+        if (activeWorkspaceIds.length > 0) {
+          this.clearWorkspaceArchiving(activeWorkspaceIds);
+        }
+      }
+
+      const updateIds =
+        removedWorkspaceIds.length > 0
+          ? removedWorkspaceIds
+          : [projectWorkspaces[0]?.workspaceId ?? projectId];
+      await this.emitWorkspaceUpdatesForWorkspaceIds(updateIds, {
+        skipReconcile: true,
+        removedProjectId: projectId,
+      });
+
+      this.emit({
+        type: "project.remove.response",
+        payload: {
+          requestId,
+          projectId,
+          accepted: true,
+          removedWorkspaceIds,
+          error: null,
+        },
+      });
+    } catch (error) {
+      this.sessionLogger.error(
+        { err: error, projectId, requestId },
+        "session: project.remove.request error",
+      );
+      this.emit({
+        type: "activity_log",
+        payload: {
+          id: uuidv4(),
+          timestamp: new Date(),
+          type: "error",
+          content: `Failed to remove project: ${getErrorMessage(error)}`,
+        },
+      });
+      this.emit({
+        type: "project.remove.response",
+        payload: {
+          requestId,
+          projectId,
+          accepted: false,
+          removedWorkspaceIds: [],
+          error: getErrorMessageOr(error, "Failed to remove project"),
+        },
+      });
+    }
+  }
+
   private async handleWorkspaceTitleSetRequest(
     workspaceId: string,
     title: string | null,
@@ -6569,7 +6676,10 @@ export class Session {
       if (existing) {
         return existing;
       }
-      const placementPromise = this.buildProjectPlacementForWorkspaceId(workspaceId);
+      const placementPromise =
+        request.type === "fetch_agent_history_request"
+          ? this.buildProjectPlacementForExistingWorkspaceProject(workspaceId)
+          : this.buildProjectPlacementForWorkspaceId(workspaceId);
       placementByWorkspaceId.set(workspaceId, placementPromise);
       return placementPromise;
     };
@@ -7023,6 +7133,9 @@ export class Session {
       input.workspace.kind === kind &&
       input.workspace.displayName === displayName
     ) {
+      if (!input.project) {
+        await this.projectRegistry.upsert(projectRecord);
+      }
       return this.ensureWorkspaceRecordUnarchived(input.workspace);
     }
 
@@ -7327,7 +7440,7 @@ export class Session {
 
   private async emitWorkspaceUpdatesForWorkspaceIds(
     workspaceIds: Iterable<string>,
-    options?: { skipReconcile?: boolean; dedupeGitState?: boolean },
+    options?: { skipReconcile?: boolean; dedupeGitState?: boolean; removedProjectId?: string },
   ): Promise<void> {
     const subscription = this.workspaceUpdatesSubscription;
     if (!subscription) {
@@ -7356,22 +7469,14 @@ export class Session {
       ) {
         continue;
       }
-      const watchTarget = this.resolveWorkspaceGitWatchTarget(workspaceId);
-      if (watchTarget && this.onBranchChanged) {
-        const newBranchName = nextWorkspace?.name ?? null;
-        if (newBranchName !== watchTarget.lastBranchName) {
-          this.onBranchChanged(workspaceId, watchTarget.lastBranchName, newBranchName);
-        }
-      }
-      this.rememberWorkspaceGitDescriptorState(workspaceId, nextWorkspace);
+      this.recordWorkspaceGitDescriptorState(workspaceId, nextWorkspace);
 
       if (!nextWorkspace) {
         subscription.lastEmittedByWorkspaceId.delete(workspaceId);
-        this.bufferOrEmitWorkspaceUpdate(subscription, {
-          kind: "remove",
-          id: workspaceId,
-          ...(await this.resolveEmptyProjectForArchivedWorkspace(workspaceId)),
-        });
+        this.bufferOrEmitWorkspaceUpdate(
+          subscription,
+          await this.buildWorkspaceRemoveUpdatePayload(workspaceId, options?.removedProjectId),
+        );
         continue;
       }
 
@@ -7397,6 +7502,34 @@ export class Session {
     }
   }
 
+  private recordWorkspaceGitDescriptorState(
+    workspaceId: string,
+    nextWorkspace: WorkspaceDescriptorPayload | null,
+  ): void {
+    const watchTarget = this.resolveWorkspaceGitWatchTarget(workspaceId);
+    if (watchTarget && this.onBranchChanged) {
+      const newBranchName = nextWorkspace?.name ?? null;
+      if (newBranchName !== watchTarget.lastBranchName) {
+        this.onBranchChanged(workspaceId, watchTarget.lastBranchName, newBranchName);
+      }
+    }
+    this.rememberWorkspaceGitDescriptorState(workspaceId, nextWorkspace);
+  }
+
+  private async buildWorkspaceRemoveUpdatePayload(
+    workspaceId: string,
+    removedProjectId?: string,
+  ): Promise<WorkspaceUpdatePayload> {
+    if (removedProjectId) {
+      return { kind: "remove", id: workspaceId, removedProjectId };
+    }
+    return {
+      kind: "remove",
+      id: workspaceId,
+      ...(await this.resolveEmptyProjectForArchivedWorkspace(workspaceId)),
+    };
+  }
+
   // When a workspace is archived its project may become empty. Resolve the
   // now-empty project parent so the `remove` update can carry it, keeping the
   // sidebar's empty project row in sync without a full re-hydration.
diff --git a/packages/server/src/server/session.workspaces.test.ts b/packages/server/src/server/session.workspaces.test.ts
index 14be43d2f..876825e5b 100644
--- a/packages/server/src/server/session.workspaces.test.ts
+++ b/packages/server/src/server/session.workspaces.test.ts
@@ -84,6 +84,7 @@ interface SessionTestAccess {
     archive(projectId: string, archivedAt: string): Promise<void>;
     get(id: string): Promise<unknown>;
     upsert(record: unknown): Promise<unknown>;
+    remove(projectId: string): Promise<void>;
   };
   agentStorage: {
     list(...args: unknown[]): Promise<unknown[]>;
@@ -2391,6 +2392,94 @@ test("fetch_agent_history_request pages archived historical rows separately", as
   expect(session.agentUpdatesSubscription).toBeNull();
 });
 
+test("fetch_agent_history_request skips rows whose workspace project record is missing", async () => {
+  const emitted: SessionOutboundMessage[] = [];
+  const session = createSessionForWorkspaceTests();
+  const stableCwd = path.resolve("/tmp/stable-history");
+  const orphanCwd = path.resolve("/tmp/orphan-history");
+  const stableProject = createPersistedProjectRecord({
+    projectId: "proj-stable-history",
+    rootPath: stableCwd,
+    kind: "non_git",
+    displayName: "stable history",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+  });
+  const stableWorkspace = createPersistedWorkspaceRecord({
+    workspaceId: "ws-stable-history",
+    projectId: stableProject.projectId,
+    cwd: stableCwd,
+    kind: "directory",
+    displayName: "stable history",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+  });
+  const orphanWorkspace = createPersistedWorkspaceRecord({
+    workspaceId: "ws-orphan-history",
+    projectId: orphanCwd,
+    cwd: orphanCwd,
+    kind: "local_checkout",
+    displayName: "main",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+  });
+
+  session.emit = (message) => {
+    if (isSessionOutboundMessage(message)) emitted.push(message);
+  };
+  session.projectRegistry.get = async (projectId: string) =>
+    projectId === stableProject.projectId ? stableProject : null;
+  session.workspaceRegistry.get = async (workspaceId: string) =>
+    [stableWorkspace, orphanWorkspace].find((workspace) => workspace.workspaceId === workspaceId) ??
+    null;
+  session.listAgentPayloads = async () => [
+    makeAgent({
+      id: "history-orphan",
+      cwd: orphanCwd,
+      workspaceId: orphanWorkspace.workspaceId,
+      status: "idle",
+      updatedAt: "2026-03-01T12:01:00.000Z",
+    }),
+    makeAgent({
+      id: "history-stable",
+      cwd: stableCwd,
+      workspaceId: stableWorkspace.workspaceId,
+      status: "closed",
+      updatedAt: "2026-03-01T12:00:00.000Z",
+    }),
+  ];
+
+  await session.handleMessage({
+    type: "fetch_agent_history_request",
+    requestId: "req-history-orphan",
+    page: { limit: 25 },
+  });
+
+  expect(emitted).toEqual([
+    {
+      type: "fetch_agent_history_response",
+      payload: expect.objectContaining({
+        requestId: "req-history-orphan",
+        entries: [
+          expect.objectContaining({
+            agent: expect.objectContaining({ id: "history-stable" }),
+            project: expect.objectContaining({
+              projectKey: stableProject.projectId,
+              projectName: "stable history",
+              workspaceName: "stable history",
+            }),
+          }),
+        ],
+        pageInfo: {
+          nextCursor: null,
+          prevCursor: null,
+          hasMore: false,
+        },
+      }),
+    },
+  ]);
+});
+
 test("fetch_recent_provider_sessions_request lists importable provider sessions by handle", async () => {
   const emitted: Array<{ type: string; payload: unknown }> = [];
   const session = createSessionForWorkspaceTests();
@@ -3035,6 +3124,182 @@ test("archiving the last workspace emits a remove carrying the now-empty project
   });
 });
 
+test("project.remove.request archives active workspaces and removes the project record", async () => {
+  const emitted: SessionOutboundMessage[] = [];
+  const session = createSessionForWorkspaceTests({
+    onMessage: (message) => emitted.push(message),
+  });
+  const project = createPersistedProjectRecord({
+    projectId: "proj-remove-with-workspace",
+    rootPath: REPO_CWD,
+    kind: "git",
+    displayName: "repo",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+  });
+  const workspace = createPersistedWorkspaceRecord({
+    workspaceId: "ws-project-remove",
+    projectId: project.projectId,
+    cwd: REPO_CWD,
+    kind: "local_checkout",
+    displayName: "main",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+  });
+  const projects = new Map<string, PersistedProjectRecord>([[project.projectId, project]]);
+  const workspaces = new Map<string, PersistedWorkspaceRecord>([
+    [workspace.workspaceId, workspace],
+  ]);
+
+  session.projectRegistry.get = async (projectId: string) => projects.get(projectId) ?? null;
+  session.projectRegistry.list = async () => Array.from(projects.values());
+  session.projectRegistry.remove = async (projectId: string) => {
+    projects.delete(projectId);
+  };
+  session.workspaceRegistry.get = async (workspaceId: string) =>
+    workspaces.get(workspaceId) ?? null;
+  session.workspaceRegistry.list = async () => Array.from(workspaces.values());
+  session.workspaceRegistry.archive = async (workspaceId: string, archivedAt: string) => {
+    const existing = workspaces.get(workspaceId);
+    if (!existing) return;
+    workspaces.set(workspaceId, { ...existing, updatedAt: archivedAt, archivedAt });
+  };
+  session.workspaceUpdatesSubscription = {
+    subscriptionId: "sub-project-remove",
+    filter: undefined,
+    isBootstrapping: false,
+    pendingUpdatesByWorkspaceId: new Map(),
+    lastEmittedByWorkspaceId: new Map(),
+  };
+  session.reconcileActiveWorkspaceRecords = async () => new Set();
+  session.listAgentPayloads = async () => [];
+  session.buildWorkspaceDescriptorMap = async (options: { workspaceIds?: Iterable<string> }) => {
+    const workspaceIds = Array.from(options.workspaceIds ?? workspaces.keys());
+    const descriptors = new Map<string, unknown>();
+    for (const workspaceId of workspaceIds) {
+      const record = workspaces.get(workspaceId);
+      if (!record || record.archivedAt) continue;
+      descriptors.set(workspaceId, {
+        id: record.workspaceId,
+        projectId: record.projectId,
+        projectDisplayName: "repo",
+        projectRootPath: REPO_CWD,
+        projectKind: "git",
+        workspaceKind: record.kind,
+        name: record.displayName,
+        status: "idle",
+        activityAt: null,
+      });
+    }
+    return descriptors;
+  };
+
+  await session.handleMessage({
+    type: "project.remove.request",
+    projectId: project.projectId,
+    requestId: "req-remove-project",
+  });
+
+  expect(projects.has(project.projectId)).toBe(false);
+  expect(workspaces.get(workspace.workspaceId)).toEqual({
+    ...workspace,
+    updatedAt: expect.any(String),
+    archivedAt: expect.any(String),
+  });
+  expect(findByType(emitted, "project.remove.response")?.payload).toEqual({
+    requestId: "req-remove-project",
+    projectId: project.projectId,
+    accepted: true,
+    removedWorkspaceIds: [workspace.workspaceId],
+    error: null,
+  });
+  const workspaceUpdates = filterByType(emitted, "workspace_update");
+  expect(workspaceUpdates.at(-1)?.payload).toEqual({
+    kind: "remove",
+    id: workspace.workspaceId,
+    removedProjectId: project.projectId,
+  });
+});
+
+test("project.remove.request removes an already-empty project", async () => {
+  const emitted: SessionOutboundMessage[] = [];
+  const session = createSessionForWorkspaceTests({
+    onMessage: (message) => emitted.push(message),
+  });
+  const project = createPersistedProjectRecord({
+    projectId: "proj-remove-empty",
+    rootPath: REPO_CWD,
+    kind: "git",
+    displayName: "repo",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+  });
+  const archivedWorkspace = createPersistedWorkspaceRecord({
+    workspaceId: "ws-project-remove-empty",
+    projectId: project.projectId,
+    cwd: REPO_CWD,
+    kind: "local_checkout",
+    displayName: "main",
+    createdAt: "2026-03-01T12:00:00.000Z",
+    updatedAt: "2026-03-01T12:00:00.000Z",
+    archivedAt: "2026-03-02T12:00:00.000Z",
+  });
+  const projects = new Map<string, PersistedProjectRecord>([[project.projectId, project]]);
+  const workspaces = new Map<string, PersistedWorkspaceRecord>([
+    [archivedWorkspace.workspaceId, archivedWorkspace],
+  ]);
+
+  session.projectRegistry.get = async (projectId: string) => projects.get(projectId) ?? null;
+  session.projectRegistry.list = async () => Array.from(projects.values());
+  session.projectRegistry.remove = async (projectId: string) => {
+    projects.delete(projectId);
+  };
+  session.workspaceRegistry.get = async (workspaceId: string) =>
+    workspaces.get(workspaceId) ?? null;
+  session.workspaceRegistry.list = async () => Array.from(workspaces.values());
+  session.workspaceRegistry.archive = async (workspaceId: string, archivedAt: string) => {
+    const existing = workspaces.get(workspaceId);
+    if (!existing) return;
+    workspaces.set(workspaceId, { ...existing, updatedAt: archivedAt, archivedAt });
+  };
+  session.workspaceUpdatesSubscription = {
+    subscriptionId: "sub-empty-project-remove",
+    filter: undefined,
+    isBootstrapping: false,
+    pendingUpdatesByWorkspaceId: new Map(),
+    lastEmittedByWorkspaceId: new Map(),
+  };
+  session.reconcileActiveWorkspaceRecords = async () => new Set();
+  session.listAgentPayloads = async () => [];
+  session.buildWorkspaceDescriptorMap = async () => new Map();
+
+  await session.handleMessage({
+    type: "project.remove.request",
+    projectId: project.projectId,
+    requestId: "req-remove-empty-project",
+  });
+
+  expect(projects.has(project.projectId)).toBe(false);
+  expect(workspaces.get(archivedWorkspace.workspaceId)).toEqual(archivedWorkspace);
+  expect(findByType(emitted, "project.remove.response")?.payload).toEqual({
+    requestId: "req-remove-empty-project",
+    projectId: project.projectId,
+    accepted: true,
+    removedWorkspaceIds: [],
+    error: null,
+  });
+  expect(filterByType(emitted, "workspace_update")).toEqual([
+    {
+      type: "workspace_update",
+      payload: {
+        kind: "remove",
+        id: archivedWorkspace.workspaceId,
+        removedProjectId: project.projectId,
+      },
+    },
+  ]);
+});
+
 test("create paseo worktree request returns a registered workspace descriptor", async () => {
   const emitted: SessionOutboundMessage[] = [];
   const createdAt = "2026-05-12T12:00:00.000Z";
@@ -4058,6 +4323,67 @@ test("open_project_request unarchives an existing archived workspace and project
   expect(response?.payload.workspace?.id).toBe(workspaceId);
 });
 
+test("open_project_request recreates a missing project record when unarchiving its workspace", async () => {
+  const emitted: SessionOutboundMessage[] = [];
+  const session = createSessionForWorkspaceTests();
+  const projects = new Map<string, ReturnType<typeof createPersistedProjectRecord>>();
+  const workspaces = new Map<string, ReturnType<typeof createPersistedWorkspaceRecord>>();
+
+  const cwd = REPO_CWD;
+  const workspaceId = "ws-repo-project-removed";
+  workspaces.set(
+    workspaceId,
+    createPersistedWorkspaceRecord({
+      workspaceId,
+      projectId: cwd,
+      cwd,
+      kind: "directory",
+      displayName: "repo",
+      createdAt: "2026-03-01T12:00:00.000Z",
+      updatedAt: "2026-03-10T00:00:00.000Z",
+      archivedAt: "2026-03-10T00:00:00.000Z",
+    }),
+  );
+
+  session.emit = (message) => {
+    if (isSessionOutboundMessage(message)) emitted.push(message);
+  };
+  session.projectRegistry.get = async (projectId: string) => projects.get(projectId) ?? null;
+  session.projectRegistry.upsert = async (
+    record: ReturnType<typeof createPersistedProjectRecord>,
+  ) => {
+    projects.set(record.projectId, record);
+  };
+  session.workspaceRegistry.get = async (lookupWorkspaceId: string) =>
+    workspaces.get(lookupWorkspaceId) ?? null;
+  session.workspaceRegistry.upsert = async (
+    record: ReturnType<typeof createPersistedWorkspaceRecord>,
+  ) => {
+    workspaces.set(record.workspaceId, record);
+  };
+  session.projectRegistry.list = async () => Array.from(projects.values());
+  session.workspaceRegistry.list = async () => Array.from(workspaces.values());
+
+  await session.handleMessage({
+    type: "open_project_request",
+    cwd,
+    requestId: "req-open-removed-project",
+  });
+
+  expect(projects.get(cwd)).toEqual(
+    expect.objectContaining({
+      projectId: cwd,
+      displayName: "repo",
+      archivedAt: null,
+    }),
+  );
+  expect(workspaces.get(workspaceId)?.archivedAt).toBeNull();
+  const response = findByType(emitted, "open_project_response");
+  expect(response?.payload.error).toBeNull();
+  expect(response?.payload.workspace?.id).toBe(workspaceId);
+  expect(response?.payload.workspace?.projectDisplayName).toBe("repo");
+});
+
 test("refresh_agent_request unarchives the owning workspace when its directory exists", async () => {
   const emitted: SessionOutboundMessage[] = [];
   const session = createSessionForWorkspaceTests({
diff --git a/packages/server/src/server/websocket-server.ts b/packages/server/src/server/websocket-server.ts
index 3e5044157..9bcbb933d 100644
--- a/packages/server/src/server/websocket-server.ts
+++ b/packages/server/src/server/websocket-server.ts
@@ -1157,6 +1157,8 @@ export class VoiceAssistantWebSocketServer {
         checkoutRefresh: true,
         // COMPAT(workspaceMultiplicity): added in v0.1.97, drop the gate when floor >= v0.1.97
         workspaceMultiplicity: true,
+        // COMPAT(projectRemove): added in v0.1.97, drop the gate when floor >= v0.1.97.
+        projectRemove: true,
         // COMPAT(worktreeRestore): added in v0.1.98, drop the gate when floor >= v0.1.98
         worktreeRestore: true,
       },