diff --git a/extensions/bluebubbles/src/attachments.test.ts b/extensions/bluebubbles/src/attachments.test.ts
index acf8e9be437..3f695861509 100644
--- a/extensions/bluebubbles/src/attachments.test.ts
+++ b/extensions/bluebubbles/src/attachments.test.ts
@@ -6,7 +6,6 @@ import {
   sendBlueBubblesAttachment,
 } from "./attachments.js";
 import { fetchBlueBubblesServerInfo, getCachedBlueBubblesPrivateApiStatus } from "./probe.js";
-import type { PluginRuntime } from "./runtime-api.js";
 import { setBlueBubblesRuntime } from "./runtime.js";
 import {
   BLUE_BUBBLES_PRIVATE_API_STATUS,
@@ -14,53 +13,27 @@ import {
   mockBlueBubblesPrivateApiStatus,
   mockBlueBubblesPrivateApiStatusOnce,
 } from "./test-harness.js";
+import {
+  createBlueBubblesFetchRemoteMediaMock,
+  createBlueBubblesRuntimeStub,
+} from "./test-helpers.js";
 import type { BlueBubblesAttachment } from "./types.js";
 
 const mockFetch = vi.fn();
 const fetchServerInfoMock = vi.mocked(fetchBlueBubblesServerInfo);
-const fetchRemoteMediaMock = vi.fn(
-  async (params: {
-    url: string;
-    maxBytes?: number;
-    fetchImpl?: (input: RequestInfo | URL, init?: RequestInit) => Promise<Response>;
-  }) => {
-    const fetchFn = params.fetchImpl ?? fetch;
-    const res = await fetchFn(params.url);
-    if (!res.ok) {
-      const text = await res.text().catch(() => "unknown");
-      throw new Error(
-        `Failed to fetch media from ${params.url}: HTTP ${res.status}; body: ${text}`,
-      );
-    }
-    const buffer = Buffer.from(await res.arrayBuffer());
-    if (typeof params.maxBytes === "number" && buffer.byteLength > params.maxBytes) {
-      const error = new Error(`payload exceeds maxBytes ${params.maxBytes}`) as Error & {
-        code?: string;
-      };
-      error.code = "max_bytes";
-      throw error;
-    }
-    return {
-      buffer,
-      contentType: res.headers.get("content-type") ?? undefined,
-      fileName: undefined,
-    };
+const fetchRemoteMediaMock = createBlueBubblesFetchRemoteMediaMock({
+  createHttpError: async ({ response, url }) => {
+    const text = await response.text().catch(() => "unknown");
+    return new Error(`Failed to fetch media from ${url}: HTTP ${response.status}; body: ${text}`);
   },
-);
+});
 
 installBlueBubblesFetchTestHooks({
   mockFetch,
   privateApiStatusMock: vi.mocked(getCachedBlueBubblesPrivateApiStatus),
 });
 
-const runtimeStub = {
-  channel: {
-    media: {
-      fetchRemoteMedia:
-        fetchRemoteMediaMock as unknown as PluginRuntime["channel"]["media"]["fetchRemoteMedia"],
-    },
-  },
-} as unknown as PluginRuntime;
+const runtimeStub = createBlueBubblesRuntimeStub(fetchRemoteMediaMock);
 
 describe("downloadBlueBubblesAttachment", () => {
   beforeEach(() => {
diff --git a/extensions/bluebubbles/src/client.test.ts b/extensions/bluebubbles/src/client.test.ts
index 407e2c4e7d6..81bc919d0ff 100644
--- a/extensions/bluebubbles/src/client.test.ts
+++ b/extensions/bluebubbles/src/client.test.ts
@@ -1,4 +1,3 @@
-import type { SsrFPolicy } from "openclaw/plugin-sdk/ssrf-runtime";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import "./test-mocks.js";
 import {
@@ -11,12 +10,15 @@ import {
   resolveBlueBubblesClientSsrfPolicy,
 } from "./client.js";
 import { getCachedBlueBubblesPrivateApiStatus } from "./probe.js";
-import type { PluginRuntime } from "./runtime-api.js";
 import { setBlueBubblesRuntime } from "./runtime.js";
 import {
   createBlueBubblesFetchGuardPassthroughInstaller,
   installBlueBubblesFetchTestHooks,
 } from "./test-harness.js";
+import {
+  createBlueBubblesFetchRemoteMediaMock,
+  createBlueBubblesRuntimeStub,
+} from "./test-helpers.js";
 import type { BlueBubblesAttachment } from "./types.js";
 import { _setFetchGuardForTesting } from "./types.js";
 
@@ -24,47 +26,16 @@ import { _setFetchGuardForTesting } from "./types.js";
 
 const mockFetch = vi.fn();
 
-const fetchRemoteMediaMock = vi.fn(
-  async (params: {
-    url: string;
-    maxBytes?: number;
-    ssrfPolicy?: SsrFPolicy;
-    fetchImpl?: (input: RequestInfo | URL, init?: RequestInit) => Promise<Response>;
-  }) => {
-    const fetchFn = params.fetchImpl ?? fetch;
-    const res = await fetchFn(params.url);
-    if (!res.ok) {
-      throw new Error(`media fetch failed: HTTP ${res.status}`);
-    }
-    const buffer = Buffer.from(await res.arrayBuffer());
-    if (typeof params.maxBytes === "number" && buffer.byteLength > params.maxBytes) {
-      const error = new Error(`payload exceeds maxBytes ${params.maxBytes}`) as Error & {
-        code?: string;
-      };
-      error.code = "max_bytes";
-      throw error;
-    }
-    return {
-      buffer,
-      contentType: res.headers.get("content-type") ?? undefined,
-      fileName: undefined,
-    };
-  },
-);
+const fetchRemoteMediaMock = createBlueBubblesFetchRemoteMediaMock({
+  createHttpError: ({ response }) => new Error(`media fetch failed: HTTP ${response.status}`),
+});
 
 installBlueBubblesFetchTestHooks({
   mockFetch,
   privateApiStatusMock: vi.mocked(getCachedBlueBubblesPrivateApiStatus),
 });
 
-const runtimeStub = {
-  channel: {
-    media: {
-      fetchRemoteMedia:
-        fetchRemoteMediaMock as unknown as PluginRuntime["channel"]["media"]["fetchRemoteMedia"],
-    },
-  },
-} as unknown as PluginRuntime;
+const runtimeStub = createBlueBubblesRuntimeStub(fetchRemoteMediaMock);
 
 beforeEach(() => {
   fetchRemoteMediaMock.mockClear();
diff --git a/extensions/bluebubbles/src/test-helpers.ts b/extensions/bluebubbles/src/test-helpers.ts
new file mode 100644
index 00000000000..1f0035ab75b
--- /dev/null
+++ b/extensions/bluebubbles/src/test-helpers.ts
@@ -0,0 +1,52 @@
+import { vi } from "vitest";
+import type { PluginRuntime } from "./runtime-api.js";
+
+type FetchRemoteMediaParams = {
+  url: string;
+  maxBytes?: number;
+  ssrfPolicy?: unknown;
+  fetchImpl?: (input: RequestInfo | URL, init?: RequestInit) => Promise<Response>;
+};
+
+type FetchRemoteMediaHttpErrorParams = {
+  response: Response;
+  url: string;
+};
+
+export function createBlueBubblesFetchRemoteMediaMock(options: {
+  createHttpError: (params: FetchRemoteMediaHttpErrorParams) => Error | Promise<Error>;
+}) {
+  return vi.fn(async (params: FetchRemoteMediaParams) => {
+    const fetchFn = params.fetchImpl ?? fetch;
+    const res = await fetchFn(params.url);
+    if (!res.ok) {
+      throw await options.createHttpError({ response: res, url: params.url });
+    }
+    const buffer = Buffer.from(await res.arrayBuffer());
+    if (typeof params.maxBytes === "number" && buffer.byteLength > params.maxBytes) {
+      const error = new Error(`payload exceeds maxBytes ${params.maxBytes}`) as Error & {
+        code?: string;
+      };
+      error.code = "max_bytes";
+      throw error;
+    }
+    return {
+      buffer,
+      contentType: res.headers.get("content-type") ?? undefined,
+      fileName: undefined,
+    };
+  });
+}
+
+export function createBlueBubblesRuntimeStub(
+  fetchRemoteMediaMock: ReturnType<typeof createBlueBubblesFetchRemoteMediaMock>,
+) {
+  return {
+    channel: {
+      media: {
+        fetchRemoteMedia:
+          fetchRemoteMediaMock as unknown as PluginRuntime["channel"]["media"]["fetchRemoteMedia"],
+      },
+    },
+  } as unknown as PluginRuntime;
+}