diff --git a/web/src/lib/intake-client.ts b/web/src/lib/intake-client.ts
index 1671d22..0cc4eaf 100644
--- a/web/src/lib/intake-client.ts
+++ b/web/src/lib/intake-client.ts
@@ -1,6 +1,7 @@
 "use client";
 
 import { createNotesApiClient } from "@/lib/api-helpers";
+import { RETRY_WHEN_ONLINE_MESSAGE, withMutationRetry } from "@/lib/mutation-retry";
 
 // ── Types ────────────────────────────────────────────────────────
 
@@ -63,9 +64,12 @@ export async function submitIntake(
   const payload: Record<string, string> = { url };
   if (workspaceId) payload.workspaceId = workspaceId;
   if (templateOverride) payload.templateOverride = templateOverride;
-  return api.fetch("/intake", {
-    method: "POST",
-    body: JSON.stringify(payload),
+  return withMutationRetry({
+    run: () => api.fetch("/intake", {
+      method: "POST",
+      body: JSON.stringify(payload),
+    }),
+    offlineMessage: RETRY_WHEN_ONLINE_MESSAGE,
   });
 }
 
@@ -98,16 +102,23 @@ export async function createIntakeRule(
   rule: Omit<IntakeRule, "id" | "userId">,
 ): Promise<IntakeRule> {
   const api = createNotesApiClient();
-  return api.fetch("/intake-rules", {
-    method: "POST",
-    body: JSON.stringify(rule),
+  return withMutationRetry({
+    run: () => api.fetch("/intake-rules", {
+      method: "POST",
+      body: JSON.stringify(rule),
+    }),
+    queue: { id: rule.name, action: "post", path: "/intake-rules", payload: rule },
   });
 }
 
 export async function deleteIntakeRule(id: string): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/intake-rules/${encodeURIComponent(id)}`, {
-    method: "DELETE",
+  const path = `/intake-rules/${encodeURIComponent(id)}`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "DELETE",
+    }),
+    queue: { id, action: "delete", path, payload: {} },
   });
 }
 
@@ -120,9 +131,13 @@ export async function shareNoteWithUser(
   permission: "view" | "comment" | "edit" = "view",
 ): Promise<unknown> {
   const api = createNotesApiClient();
-  return api.fetch(`/notes/${encodeURIComponent(noteId)}/share-with-user`, {
-    method: "POST",
-    body: JSON.stringify({ workspaceId, sharedWithUserId, permission }),
+  const path = `/notes/${encodeURIComponent(noteId)}/share-with-user`;
+  return withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "POST",
+      body: JSON.stringify({ workspaceId, sharedWithUserId, permission }),
+    }),
+    offlineMessage: RETRY_WHEN_ONLINE_MESSAGE,
   });
 }
 
@@ -146,8 +161,12 @@ export async function removeCollaborator(
   userId: string,
 ): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/notes/${encodeURIComponent(noteId)}/collaborators/${encodeURIComponent(userId)}`, {
-    method: "DELETE",
+  const path = `/notes/${encodeURIComponent(noteId)}/collaborators/${encodeURIComponent(userId)}`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "DELETE",
+    }),
+    offlineMessage: RETRY_WHEN_ONLINE_MESSAGE,
   });
 }
 
diff --git a/web/src/lib/mutation-retry.test.ts b/web/src/lib/mutation-retry.test.ts
new file mode 100644
index 0000000..1eb7025
--- /dev/null
+++ b/web/src/lib/mutation-retry.test.ts
@@ -0,0 +1,72 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { OFFLINE_QUEUE_MESSAGE, RETRY_WHEN_ONLINE_MESSAGE, withMutationRetry } from "@/lib/mutation-retry";
+
+const enqueueMock = vi.fn();
+
+vi.mock("@/lib/offline-queue", () => ({
+  getOfflineQueue: () => ({ enqueue: enqueueMock }),
+}));
+
+function setOnline(value: boolean) {
+  Object.defineProperty(navigator, "onLine", {
+    configurable: true,
+    value,
+  });
+}
+
+describe("withMutationRetry", () => {
+  beforeEach(() => {
+    enqueueMock.mockClear();
+    setOnline(true);
+  });
+
+  it("returns the mutation result when the operation succeeds", async () => {
+    await expect(withMutationRetry({ run: async () => "ok" })).resolves.toBe("ok");
+    expect(enqueueMock).not.toHaveBeenCalled();
+  });
+
+  it("queues retryable mutations while offline and throws a clear queued message", async () => {
+    setOnline(false);
+
+    await expect(withMutationRetry({
+      run: async () => { throw new Error("Failed to fetch"); },
+      queue: {
+        id: "note-1",
+        action: "patch",
+        path: "/notes/note-1?workspaceId=ws-1",
+        payload: { title: "Offline edit" },
+      },
+    })).rejects.toThrow(OFFLINE_QUEUE_MESSAGE);
+
+    expect(enqueueMock).toHaveBeenCalledWith({
+      id: "note-1",
+      action: "patch",
+      path: "/notes/note-1?workspaceId=ws-1",
+      payload: { title: "Offline edit" },
+    });
+  });
+
+  it("uses clear retry UX for offline mutations that need immediate server results", async () => {
+    setOnline(false);
+
+    await expect(withMutationRetry({
+      run: async () => { throw new Error("Failed to fetch"); },
+    })).rejects.toThrow(RETRY_WHEN_ONLINE_MESSAGE);
+
+    expect(enqueueMock).not.toHaveBeenCalled();
+  });
+
+  it("does not queue validation or server errors while online", async () => {
+    await expect(withMutationRetry({
+      run: async () => { throw new Error("Validation failed"); },
+      queue: {
+        id: "note-1",
+        action: "patch",
+        path: "/notes/note-1",
+        payload: {},
+      },
+    })).rejects.toThrow("Validation failed");
+
+    expect(enqueueMock).not.toHaveBeenCalled();
+  });
+});
diff --git a/web/src/lib/mutation-retry.ts b/web/src/lib/mutation-retry.ts
new file mode 100644
index 0000000..4119b69
--- /dev/null
+++ b/web/src/lib/mutation-retry.ts
@@ -0,0 +1,44 @@
+"use client";
+
+import { getOfflineQueue } from "@/lib/offline-queue";
+
+export const OFFLINE_QUEUE_MESSAGE = "You are offline. This change was saved and will retry automatically.";
+export const RETRY_WHEN_ONLINE_MESSAGE = "You are offline. Reconnect and try again.";
+
+type QueueAction = "post" | "patch" | "delete" | "create" | "update";
+
+interface RetryableMutation<T> {
+  run: () => Promise<T>;
+  queue?: {
+    id: string;
+    action: QueueAction;
+    path: string;
+    payload: Record<string, unknown>;
+  };
+  offlineMessage?: string;
+}
+
+export function isOffline(): boolean {
+  return typeof navigator !== "undefined" && navigator.onLine === false;
+}
+
+export async function withMutationRetry<T>({
+  run,
+  queue,
+  offlineMessage,
+}: RetryableMutation<T>): Promise<T> {
+  try {
+    return await run();
+  } catch (error) {
+    if (!isOffline()) {
+      throw error;
+    }
+
+    if (queue) {
+      getOfflineQueue().enqueue(queue);
+      throw new Error(offlineMessage ?? OFFLINE_QUEUE_MESSAGE);
+    }
+
+    throw new Error(offlineMessage ?? RETRY_WHEN_ONLINE_MESSAGE);
+  }
+}
diff --git a/web/src/lib/notes-client.test.ts b/web/src/lib/notes-client.test.ts
index 321730b..53a18e9 100644
--- a/web/src/lib/notes-client.test.ts
+++ b/web/src/lib/notes-client.test.ts
@@ -1,6 +1,7 @@
 import { describe, expect, it, vi, beforeEach } from "vitest";
 
 const fetchMock = vi.fn();
+const enqueueMock = vi.fn();
 
 vi.mock("@bytelyst/api-client", () => ({
   createApiClient: () => ({
@@ -8,11 +9,25 @@ vi.mock("@bytelyst/api-client", () => ({
   }),
 }));
 
-import { getNoteDetail } from "@/lib/notes-client";
+vi.mock("@/lib/offline-queue", () => ({
+  getOfflineQueue: () => ({ enqueue: enqueueMock }),
+}));
+
+import { createNote, getNoteDetail, updateNoteDetail } from "@/lib/notes-client";
+import { OFFLINE_QUEUE_MESSAGE } from "@/lib/mutation-retry";
+
+function setOnline(value: boolean) {
+  Object.defineProperty(navigator, "onLine", {
+    configurable: true,
+    value,
+  });
+}
 
 describe("getNoteDetail", () => {
   beforeEach(() => {
     fetchMock.mockReset();
+    enqueueMock.mockClear();
+    setOnline(true);
   });
 
   it("returns persisted tasks only, preserves artifact blob metadata, and normalizes review state", async () => {
@@ -131,3 +146,41 @@ describe("getNoteDetail", () => {
     expect(note).toBeNull();
   });
 });
+
+describe("retryable note mutations", () => {
+  beforeEach(() => {
+    fetchMock.mockReset();
+    enqueueMock.mockClear();
+    setOnline(true);
+  });
+
+  it("queues note updates when the browser is offline", async () => {
+    setOnline(false);
+    fetchMock.mockRejectedValue(new Error("Failed to fetch"));
+
+    await expect(updateNoteDetail("note-1", "ws-1", { title: "Offline edit" }))
+      .rejects.toThrow(OFFLINE_QUEUE_MESSAGE);
+
+    expect(enqueueMock).toHaveBeenCalledWith({
+      id: "note-1",
+      action: "patch",
+      path: "/notes/note-1?workspaceId=ws-1",
+      payload: { title: "Offline edit" },
+    });
+  });
+
+  it("queues note creation when the browser is offline", async () => {
+    setOnline(false);
+    fetchMock.mockRejectedValue(new Error("Failed to fetch"));
+
+    const input = { id: "note-new", workspaceId: "ws-1", title: "New", body: "Body" };
+    await expect(createNote(input)).rejects.toThrow(OFFLINE_QUEUE_MESSAGE);
+
+    expect(enqueueMock).toHaveBeenCalledWith({
+      id: "note-new",
+      action: "post",
+      path: "/notes",
+      payload: input,
+    });
+  });
+});
diff --git a/web/src/lib/notes-client.ts b/web/src/lib/notes-client.ts
index e0f3dff..7cd98e2 100644
--- a/web/src/lib/notes-client.ts
+++ b/web/src/lib/notes-client.ts
@@ -1,6 +1,7 @@
 "use client";
 
 import { createNotesApiClient } from "@/lib/api-helpers";
+import { withMutationRetry } from "@/lib/mutation-retry";
 import type {
   AgentTimelineItem,
   ArtifactSummary,
@@ -264,13 +265,14 @@ export async function updateNoteDetail(
   },
 ): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(
-    `/notes/${encodeURIComponent(noteId)}?workspaceId=${encodeURIComponent(workspaceId)}`,
-    {
+  const path = `/notes/${encodeURIComponent(noteId)}?workspaceId=${encodeURIComponent(workspaceId)}`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
       method: "PATCH",
       body: JSON.stringify(updates),
-    },
-  );
+    }),
+    queue: { id: noteId, action: "patch", path, payload: updates },
+  });
 }
 
 export async function createNoteArtifact(input: {
@@ -285,9 +287,12 @@ export async function createNoteArtifact(input: {
   sizeBytes?: number;
 }): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch("/note-artifacts", {
-    method: "POST",
-    body: JSON.stringify(input),
+  await withMutationRetry({
+    run: () => api.fetch("/note-artifacts", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    queue: { id: input.id, action: "post", path: "/note-artifacts", payload: input },
   });
 }
 
@@ -301,9 +306,12 @@ export async function createNoteTask(input: {
   source?: "manual" | "extracted";
 }): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch("/note-tasks", {
-    method: "POST",
-    body: JSON.stringify(input),
+  await withMutationRetry({
+    run: () => api.fetch("/note-tasks", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    queue: { id: input.id, action: "post", path: "/note-tasks", payload: input },
   });
 }
 
@@ -391,25 +399,36 @@ export async function createNote(input: {
   sourceType?: string;
 }): Promise<NoteDoc> {
   const api = createNotesApiClient();
-  return api.fetch<NoteDoc>("/notes", {
-    method: "POST",
-    body: JSON.stringify(input),
+  return withMutationRetry({
+    run: () => api.fetch<NoteDoc>("/notes", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    queue: { id: input.id, action: "post", path: "/notes", payload: input },
   });
 }
 
 export async function archiveNote(noteId: string, workspaceId: string): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/notes/${encodeURIComponent(noteId)}/archive`, {
-    method: "POST",
-    body: JSON.stringify({ workspaceId }),
+  const path = `/notes/${encodeURIComponent(noteId)}/archive`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "POST",
+      body: JSON.stringify({ workspaceId }),
+    }),
+    queue: { id: `${noteId}:archive`, action: "post", path, payload: { workspaceId } },
   });
 }
 
 export async function restoreNote(noteId: string, workspaceId: string): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/notes/${encodeURIComponent(noteId)}/restore`, {
-    method: "POST",
-    body: JSON.stringify({ workspaceId }),
+  const path = `/notes/${encodeURIComponent(noteId)}/restore`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "POST",
+      body: JSON.stringify({ workspaceId }),
+    }),
+    queue: { id: `${noteId}:restore`, action: "post", path, payload: { workspaceId } },
   });
 }
 
@@ -435,9 +454,12 @@ export async function createWorkspace(input: {
   description?: string;
 }): Promise<WorkspaceDoc> {
   const api = createNotesApiClient();
-  return api.fetch<WorkspaceDoc>("/workspaces", {
-    method: "POST",
-    body: JSON.stringify(input),
+  return withMutationRetry({
+    run: () => api.fetch<WorkspaceDoc>("/workspaces", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    queue: { id: input.id, action: "post", path: "/workspaces", payload: input },
   });
 }
 
@@ -446,16 +468,24 @@ export async function updateWorkspace(
   updates: { name?: string; description?: string },
 ): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/workspaces/${encodeURIComponent(workspaceId)}`, {
-    method: "PATCH",
-    body: JSON.stringify(updates),
+  const path = `/workspaces/${encodeURIComponent(workspaceId)}`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "PATCH",
+      body: JSON.stringify(updates),
+    }),
+    queue: { id: workspaceId, action: "patch", path, payload: updates },
   });
 }
 
 export async function deleteWorkspace(workspaceId: string): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/workspaces/${encodeURIComponent(workspaceId)}`, {
-    method: "DELETE",
+  const path = `/workspaces/${encodeURIComponent(workspaceId)}`;
+  await withMutationRetry({
+    run: () => api.fetch(path, {
+      method: "DELETE",
+    }),
+    queue: { id: workspaceId, action: "delete", path, payload: {} },
   });
 }
 
@@ -467,8 +497,11 @@ export async function createNoteRelationship(input: {
   relationshipType: string;
 }): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch("/note-relationships", {
-    method: "POST",
-    body: JSON.stringify(input),
+  await withMutationRetry({
+    run: () => api.fetch("/note-relationships", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    queue: { id: input.id, action: "post", path: "/note-relationships", payload: input },
   });
 }
diff --git a/web/src/lib/offline-queue.ts b/web/src/lib/offline-queue.ts
index 7f27934..6341134 100644
--- a/web/src/lib/offline-queue.ts
+++ b/web/src/lib/offline-queue.ts
@@ -6,7 +6,9 @@ import { createNotesApiClient } from "@/lib/api-helpers";
 
 const ACTION_METHOD: Record<string, string> = {
   create: "POST",
+  post: "POST",
   update: "PATCH",
+  patch: "PATCH",
   delete: "DELETE",
 };
 
diff --git a/web/src/lib/prompt-client.test.ts b/web/src/lib/prompt-client.test.ts
index 1e19979..536b9cc 100644
--- a/web/src/lib/prompt-client.test.ts
+++ b/web/src/lib/prompt-client.test.ts
@@ -23,10 +23,19 @@ import {
   getKnowledgeGaps,
   listPromptHistory,
 } from "@/lib/prompt-client";
+import { RETRY_WHEN_ONLINE_MESSAGE } from "@/lib/mutation-retry";
+
+function setOnline(value: boolean) {
+  Object.defineProperty(navigator, "onLine", {
+    configurable: true,
+    value,
+  });
+}
 
 describe("prompt-client", () => {
   beforeEach(() => {
     fetchMock.mockReset();
+    setOnline(true);
   });
 
   it("listPromptTemplates returns items array", async () => {
@@ -68,6 +77,14 @@ describe("prompt-client", () => {
     expect(result.content).toBe("Summary");
   });
 
+  it("runPrompt gives clear retry UX when offline", async () => {
+    setOnline(false);
+    fetchMock.mockRejectedValue(new Error("Failed to fetch"));
+
+    await expect(runPrompt({ templateId: "summarize", noteId: "n1", workspaceId: "ws1" }))
+      .rejects.toThrow(RETRY_WHEN_ONLINE_MESSAGE);
+  });
+
   it("suggestTags returns tag array", async () => {
     fetchMock.mockResolvedValue({ tags: ["tag1", "tag2"] });
     const tags = await suggestTags("n1", "ws1");
diff --git a/web/src/lib/prompt-client.ts b/web/src/lib/prompt-client.ts
index d69e9da..0142514 100644
--- a/web/src/lib/prompt-client.ts
+++ b/web/src/lib/prompt-client.ts
@@ -1,6 +1,7 @@
 "use client";
 
 import { createNotesApiClient, getAccessToken } from "@/lib/api-helpers";
+import { RETRY_WHEN_ONLINE_MESSAGE, withMutationRetry } from "@/lib/mutation-retry";
 import type {
   PromptTemplate,
   RunPromptInput,
@@ -26,24 +27,34 @@ export async function createPromptTemplate(
   input: Omit<PromptTemplate, "id" | "isBuiltin">,
 ): Promise<PromptTemplate> {
   const api = createNotesApiClient();
-  return api.fetch<PromptTemplate>("/note-prompts", {
-    method: "POST",
-    body: JSON.stringify(input),
+  return withMutationRetry({
+    run: () => api.fetch<PromptTemplate>("/note-prompts", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    queue: { id: input.slug, action: "post", path: "/note-prompts", payload: input },
   });
 }
 
 export async function deletePromptTemplate(id: string): Promise<void> {
   const api = createNotesApiClient();
-  await api.fetch(`/note-prompts/${encodeURIComponent(id)}`, { method: "DELETE" });
+  const path = `/note-prompts/${encodeURIComponent(id)}`;
+  await withMutationRetry({
+    run: () => api.fetch(path, { method: "DELETE" }),
+    queue: { id, action: "delete", path, payload: {} },
+  });
 }
 
 // ── Run prompts ───────────────────────────────────────────────
 
 export async function runPrompt(input: RunPromptInput): Promise<RunPromptOutput> {
   const api = createNotesApiClient();
-  return api.fetch<RunPromptOutput>("/note-prompts/run", {
-    method: "POST",
-    body: JSON.stringify(input),
+  return withMutationRetry({
+    run: () => api.fetch<RunPromptOutput>("/note-prompts/run", {
+      method: "POST",
+      body: JSON.stringify(input),
+    }),
+    offlineMessage: RETRY_WHEN_ONLINE_MESSAGE,
   });
 }
 
diff --git a/web/src/lib/review-client.ts b/web/src/lib/review-client.ts
index d66e4c5..a8dbe8c 100644
--- a/web/src/lib/review-client.ts
+++ b/web/src/lib/review-client.ts
@@ -1,4 +1,5 @@
 import { createNotesApiClient } from "@/lib/api-helpers";
+import { RETRY_WHEN_ONLINE_MESSAGE, withMutationRetry } from "@/lib/mutation-retry";
 import type { AgentTimelineItem, ApprovalQueueItem, NoteAgentActionDoc, NoteAgentActionListResponse } from "@/lib/types";
 
 
@@ -46,18 +47,19 @@ async function updateAgentActionState(
   reviewNote?: string,
 ): Promise<NoteAgentActionDoc> {
   const api = createNotesApiClient();
+  const path = `/note-agent-actions/${encodeURIComponent(id)}?workspaceId=${encodeURIComponent(workspaceId)}`;
 
-  return api.fetch<NoteAgentActionDoc>(
-    `/note-agent-actions/${encodeURIComponent(id)}?workspaceId=${encodeURIComponent(workspaceId)}`,
-    {
+  return withMutationRetry({
+    run: () => api.fetch<NoteAgentActionDoc>(path, {
       method: "PATCH",
       body: JSON.stringify({
         state,
         reviewedAt: new Date().toISOString(),
         ...(reviewNote ? { reviewNote } : {}),
       }),
-    },
-  );
+    }),
+    offlineMessage: RETRY_WHEN_ONLINE_MESSAGE,
+  });
 }
 
 export async function listApprovalQueue(): Promise<ApprovalQueueItem[]> {
@@ -93,16 +95,16 @@ export async function batchReviewItems(
   reviewNote?: string,
 ): Promise<{ updated: number; total: number }> {
   const api = createNotesApiClient();
-  const result = await api.fetch<{ updated: number; total: number }>(
-    "/note-agent-actions/batch-review",
-    {
+  const result = await withMutationRetry({
+    run: () => api.fetch<{ updated: number; total: number }>("/note-agent-actions/batch-review", {
       method: "POST",
       body: JSON.stringify({
         ids: items.map((item) => ({ id: item.id, workspaceId: item.workspaceId })),
         state,
         ...(reviewNote ? { reviewNote } : {}),
       }),
-    },
-  );
+    }),
+    offlineMessage: RETRY_WHEN_ONLINE_MESSAGE,
+  });
   return result;
 }