diff --git a/src/agents/pi-embedded-runner/extra-params.google.test.ts b/src/agents/pi-embedded-runner/extra-params.google.test.ts
index e37ed4a872a..1a026a2ed3a 100644
--- a/src/agents/pi-embedded-runner/extra-params.google.test.ts
+++ b/src/agents/pi-embedded-runner/extra-params.google.test.ts
@@ -1,6 +1,6 @@
 import type { Model } from "@mariozechner/pi-ai";
 import { describe, expect, it, vi } from "vitest";
-import { createPiAiStreamSimpleMock } from "./extra-params.pi-ai-mock.js";
+import { createPiAiStreamSimpleMock } from "../../../test/helpers/agents/pi-ai-stream-simple-mock.js";
 import { runExtraParamsCase } from "./extra-params.test-support.js";
 
 vi.mock("@mariozechner/pi-ai", async () =>
diff --git a/src/agents/pi-embedded-runner/extra-params.zai-tool-stream.test.ts b/src/agents/pi-embedded-runner/extra-params.zai-tool-stream.test.ts
index b372a7ca1bd..cf827e4a032 100644
--- a/src/agents/pi-embedded-runner/extra-params.zai-tool-stream.test.ts
+++ b/src/agents/pi-embedded-runner/extra-params.zai-tool-stream.test.ts
@@ -1,7 +1,7 @@
 import type { Model, SimpleStreamOptions } from "@mariozechner/pi-ai";
 import { describe, expect, it, vi } from "vitest";
+import { createPiAiStreamSimpleMock } from "../../../test/helpers/agents/pi-ai-stream-simple-mock.js";
 import type { OpenClawConfig } from "../../config/config.js";
-import { createPiAiStreamSimpleMock } from "./extra-params.pi-ai-mock.js";
 import { runExtraParamsCase } from "./extra-params.test-support.js";
 
 vi.mock("@mariozechner/pi-ai", async () =>
diff --git a/src/config/heartbeat-config-honor.inventory.test.ts b/src/config/heartbeat-config-honor.inventory.test.ts
index 749d711a5d2..b6df00e5583 100644
--- a/src/config/heartbeat-config-honor.inventory.test.ts
+++ b/src/config/heartbeat-config-honor.inventory.test.ts
@@ -1,9 +1,12 @@
 import { describe, expect, it } from "vitest";
-import { auditConfigHonorInventory, listSchemaLeafKeysForPrefixes } from "./config-honor-audit.js";
+import {
+  auditConfigHonorInventory,
+  listSchemaLeafKeysForPrefixes,
+} from "../../test/helpers/config/config-honor-audit.js";
 import {
   HEARTBEAT_CONFIG_HONOR_INVENTORY,
   HEARTBEAT_CONFIG_PREFIXES,
-} from "./heartbeat-config-honor.inventory.js";
+} from "../../test/helpers/config/heartbeat-config-honor.inventory.js";
 
 const EXPECTED_HEARTBEAT_KEYS = [
   "every",
diff --git a/src/config/redact-snapshot.restore.test.ts b/src/config/redact-snapshot.restore.test.ts
index dddc5f558ac..4f0184deaf2 100644
--- a/src/config/redact-snapshot.restore.test.ts
+++ b/src/config/redact-snapshot.restore.test.ts
@@ -1,11 +1,11 @@
 import { describe, expect, it } from "vitest";
+import { redactSnapshotTestHints as mainSchemaHints } from "../../test/helpers/config/redact-snapshot-test-hints.js";
 import {
   REDACTED_SENTINEL,
   redactConfigSnapshot,
   restoreRedactedValues as restoreRedactedValues_orig,
 } from "./redact-snapshot.js";
 import { makeSnapshot, restoreRedactedValues } from "./redact-snapshot.test-helpers.js";
-import { redactSnapshotTestHints as mainSchemaHints } from "./redact-snapshot.test-hints.js";
 import type { ConfigUiHints } from "./schema.js";
 
 describe("restoreRedactedValues", () => {
diff --git a/src/config/redact-snapshot.schema.test.ts b/src/config/redact-snapshot.schema.test.ts
index 5f4335abc11..411b4c1829d 100644
--- a/src/config/redact-snapshot.schema.test.ts
+++ b/src/config/redact-snapshot.schema.test.ts
@@ -1,7 +1,7 @@
 import { describe, expect, it } from "vitest";
+import { redactSnapshotTestHints as mainSchemaHints } from "../../test/helpers/config/redact-snapshot-test-hints.js";
 import { REDACTED_SENTINEL, redactConfigSnapshot } from "./redact-snapshot.js";
 import { makeSnapshot, restoreRedactedValues } from "./redact-snapshot.test-helpers.js";
-import { redactSnapshotTestHints as mainSchemaHints } from "./redact-snapshot.test-hints.js";
 import { buildConfigSchema } from "./schema.js";
 
 describe("realredactConfigSnapshot_real", () => {
diff --git a/src/config/redact-snapshot.test.ts b/src/config/redact-snapshot.test.ts
index 5753b333236..0205add7190 100644
--- a/src/config/redact-snapshot.test.ts
+++ b/src/config/redact-snapshot.test.ts
@@ -1,12 +1,12 @@
 import JSON5 from "json5";
 import { describe, expect, it } from "vitest";
+import { redactSnapshotTestHints as mainSchemaHints } from "../../test/helpers/config/redact-snapshot-test-hints.js";
 import { REDACTED_SENTINEL, redactConfigSnapshot } from "./redact-snapshot.js";
 import {
   makeSnapshot,
   restoreRedactedValues,
   type TestSnapshot,
 } from "./redact-snapshot.test-helpers.js";
-import { redactSnapshotTestHints as mainSchemaHints } from "./redact-snapshot.test-hints.js";
 import { buildConfigSchema, type ConfigUiHints } from "./schema.js";
 import type { ConfigFileSnapshot } from "./types.openclaw.js";
 
diff --git a/src/infra/heartbeat-runner.test-harness.ts b/src/infra/heartbeat-runner.test-harness.ts
index 6137f9555ed..0528b2920c1 100644
--- a/src/infra/heartbeat-runner.test-harness.ts
+++ b/src/infra/heartbeat-runner.test-harness.ts
@@ -1,11 +1,11 @@
 import { beforeEach } from "vitest";
-import { setActivePluginRegistry } from "../plugins/runtime.js";
-import { createTestRegistry } from "../test-utils/channel-plugins.js";
 import {
   heartbeatRunnerSlackPlugin,
   heartbeatRunnerTelegramPlugin,
   heartbeatRunnerWhatsAppPlugin,
-} from "./heartbeat-runner.test-channel-plugins.js";
+} from "../../test/helpers/infra/heartbeat-runner-channel-plugins.js";
+import { setActivePluginRegistry } from "../plugins/runtime.js";
+import { createTestRegistry } from "../test-utils/channel-plugins.js";
 
 export function installHeartbeatRunnerTestRuntime(params?: { includeSlack?: boolean }): void {
   beforeEach(() => {
diff --git a/src/infra/heartbeat-runner.test-utils.ts b/src/infra/heartbeat-runner.test-utils.ts
index 2da1a22bf12..e5d7bcd01d5 100644
--- a/src/infra/heartbeat-runner.test-utils.ts
+++ b/src/infra/heartbeat-runner.test-utils.ts
@@ -2,12 +2,12 @@ import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
 import { vi } from "vitest";
+import { heartbeatRunnerTelegramPlugin } from "../../test/helpers/infra/heartbeat-runner-channel-plugins.js";
 import type { OpenClawConfig } from "../config/config.js";
 import { resolveMainSessionKey } from "../config/sessions.js";
 import { setActivePluginRegistry } from "../plugins/runtime.js";
 import { createTestRegistry } from "../test-utils/channel-plugins.js";
 import type { HeartbeatDeps } from "./heartbeat-runner.js";
-import { heartbeatRunnerTelegramPlugin } from "./heartbeat-runner.test-channel-plugins.js";
 
 export type HeartbeatSessionSeed = {
   sessionId?: string;
diff --git a/src/infra/outbound/deliver.test-helpers.ts b/src/infra/outbound/deliver.test-helpers.ts
index b5c4329b65e..c99900362af 100644
--- a/src/infra/outbound/deliver.test-helpers.ts
+++ b/src/infra/outbound/deliver.test-helpers.ts
@@ -1,5 +1,10 @@
 import { vi } from "vitest";
 import { createIMessageTestPlugin } from "../../../test/helpers/channels/imessage-test-plugin.js";
+import {
+  imessageOutboundForTest,
+  signalOutbound,
+  whatsappOutbound,
+} from "../../../test/helpers/infra/deliver-test-outbounds.js";
 import type { OpenClawConfig } from "../../config/config.js";
 import {
   releasePinnedPluginChannelRegistry,
@@ -8,11 +13,6 @@ import {
 import { createOutboundTestPlugin, createTestRegistry } from "../../test-utils/channel-plugins.js";
 import { createInternalHookEventPayload } from "../../test-utils/internal-hook-event-payload.js";
 import type { DeliverOutboundPayloadsParams, OutboundDeliveryResult } from "./deliver.js";
-import {
-  imessageOutboundForTest,
-  signalOutbound,
-  whatsappOutbound,
-} from "./deliver.test-outbounds.js";
 
 type DeliverMockState = {
   sessions: {
diff --git a/src/infra/outbound/deliver.test.ts b/src/infra/outbound/deliver.test.ts
index 1e863746bab..495b5a917bf 100644
--- a/src/infra/outbound/deliver.test.ts
+++ b/src/infra/outbound/deliver.test.ts
@@ -1,6 +1,11 @@
 import path from "node:path";
 import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
 import { createIMessageTestPlugin } from "../../../test/helpers/channels/imessage-test-plugin.js";
+import {
+  imessageOutboundForTest,
+  signalOutbound,
+  whatsappOutbound,
+} from "../../../test/helpers/infra/deliver-test-outbounds.js";
 import type { OpenClawConfig } from "../../config/config.js";
 import { createHookRunner } from "../../plugins/hooks.js";
 import { addTestHook } from "../../plugins/hooks.test-helpers.js";
@@ -13,11 +18,6 @@ import type { PluginHookRegistration } from "../../plugins/types.js";
 import { createOutboundTestPlugin, createTestRegistry } from "../../test-utils/channel-plugins.js";
 import { createInternalHookEventPayload } from "../../test-utils/internal-hook-event-payload.js";
 import { resolvePreferredOpenClawTmpDir } from "../tmp-openclaw-dir.js";
-import {
-  imessageOutboundForTest,
-  signalOutbound,
-  whatsappOutbound,
-} from "./deliver.test-outbounds.js";
 
 const mocks = vi.hoisted(() => ({
   appendAssistantMessageToSessionTranscript: vi.fn(async () => ({ ok: true, sessionFile: "x" })),
diff --git a/src/agents/pi-embedded-runner/extra-params.pi-ai-mock.ts b/test/helpers/agents/pi-ai-stream-simple-mock.ts
similarity index 100%
rename from src/agents/pi-embedded-runner/extra-params.pi-ai-mock.ts
rename to test/helpers/agents/pi-ai-stream-simple-mock.ts
diff --git a/src/config/config-honor-audit.ts b/test/helpers/config/config-honor-audit.ts
similarity index 96%
rename from src/config/config-honor-audit.ts
rename to test/helpers/config/config-honor-audit.ts
index 3690469d397..c269223fb8e 100644
--- a/src/config/config-honor-audit.ts
+++ b/test/helpers/config/config-honor-audit.ts
@@ -1,7 +1,7 @@
 import fs from "node:fs";
 import path from "node:path";
 import { fileURLToPath } from "node:url";
-import { GENERATED_BASE_CONFIG_SCHEMA } from "./schema.base.generated.js";
+import { GENERATED_BASE_CONFIG_SCHEMA } from "../../../src/config/schema.base.generated.js";
 
 export type ConfigHonorInventoryRow = {
   key: string;
@@ -34,7 +34,7 @@ export type ConfigHonorAuditResult = {
   }>;
 };
 
-const REPO_ROOT = fileURLToPath(new URL("../../", import.meta.url));
+const REPO_ROOT = fileURLToPath(new URL("../../../", import.meta.url));
 
 function hasSchemaPath(schemaPath: string): boolean {
   const segments = schemaPath.split(".");
diff --git a/src/config/heartbeat-config-honor.inventory.ts b/test/helpers/config/heartbeat-config-honor.inventory.ts
similarity index 100%
rename from src/config/heartbeat-config-honor.inventory.ts
rename to test/helpers/config/heartbeat-config-honor.inventory.ts
diff --git a/src/config/redact-snapshot.test-hints.ts b/test/helpers/config/redact-snapshot-test-hints.ts
similarity index 92%
rename from src/config/redact-snapshot.test-hints.ts
rename to test/helpers/config/redact-snapshot-test-hints.ts
index 354f89f9026..9f09a614dbd 100644
--- a/src/config/redact-snapshot.test-hints.ts
+++ b/test/helpers/config/redact-snapshot-test-hints.ts
@@ -1,4 +1,4 @@
-import type { ConfigUiHints } from "./schema.js";
+import type { ConfigUiHints } from "../../../src/config/schema.js";
 
 // Keep this fixture minimal so redaction tests exercise the hint-matching
 // behavior they care about without paying to build the full config schema graph.
diff --git a/src/infra/outbound/deliver.test-outbounds.ts b/test/helpers/infra/deliver-test-outbounds.ts
similarity index 79%
rename from src/infra/outbound/deliver.test-outbounds.ts
rename to test/helpers/infra/deliver-test-outbounds.ts
index 549bb6242e1..9768e2feaa0 100644
--- a/src/infra/outbound/deliver.test-outbounds.ts
+++ b/test/helpers/infra/deliver-test-outbounds.ts
@@ -1,8 +1,11 @@
-import { chunkMarkdownTextWithMode, chunkText } from "../../auto-reply/chunk.js";
-import type { ChannelOutboundAdapter } from "../../channels/plugins/types.js";
-import type { OpenClawConfig } from "../../config/config.js";
-import { sanitizeForPlainText } from "../../plugin-sdk/outbound-runtime.js";
-import { resolveOutboundSendDep, type OutboundSendDeps } from "./send-deps.js";
+import { chunkMarkdownTextWithMode, chunkText } from "../../../src/auto-reply/chunk.js";
+import type { ChannelOutboundAdapter } from "../../../src/channels/plugins/types.js";
+import type { OpenClawConfig } from "../../../src/config/config.js";
+import {
+  resolveOutboundSendDep,
+  type OutboundSendDeps,
+} from "../../../src/infra/outbound/send-deps.js";
+import { sanitizeForPlainText } from "../../../src/plugin-sdk/outbound-runtime.js";
 
 type SignalSendFn = (
   to: string,
@@ -53,8 +56,6 @@ function withSignalChannel(result: Awaited<ReturnType<SignalSendFn>>) {
   };
 }
 
-// Keep deliver-core tests on a light local Signal stub. The real adapter owns
-// markdown/style correctness in extensions/signal tests.
 export const signalOutbound: ChannelOutboundAdapter = {
   deliveryMode: "direct",
   textChunkLimit: 4000,
@@ -218,40 +219,36 @@ function resolveIMessageSender(deps: OutboundSendDeps | undefined) {
     ) => Promise<{ messageId: string; chatId?: string }>
   >(deps, "imessage");
   if (!sender) {
-    throw new Error("missing imessage dep");
+    throw new Error("missing sendIMessage dep");
   }
   return sender;
 }
 
-function resolveIMessageMaxBytes(cfg: OpenClawConfig): number | undefined {
-  const channelMb = (cfg.channels?.imessage as { mediaMaxMb?: number } | undefined)?.mediaMaxMb;
-  const agentMb = cfg.agents?.defaults?.mediaMaxMb;
-  const mediaMaxMb = channelMb ?? agentMb;
-  return typeof mediaMaxMb === "number" ? mediaMaxMb * MB : undefined;
+function withIMessageChannel(
+  result: Awaited<ReturnType<ReturnType<typeof resolveIMessageSender>>>,
+) {
+  return {
+    channel: "imessage" as const,
+    ...result,
+  };
 }
 
 export const imessageOutboundForTest: ChannelOutboundAdapter = {
   deliveryMode: "direct",
-  sendText: async ({ cfg, to, text, accountId, replyToId, deps }) =>
-    ({
-      channel: "imessage",
-      ...(await resolveIMessageSender(deps)(to, text, {
-        config: cfg,
-        maxBytes: resolveIMessageMaxBytes(cfg),
+  sanitizeText: ({ text }) => text,
+  sendText: async ({ to, text, accountId, deps }) =>
+    withIMessageChannel(
+      await resolveIMessageSender(deps)(to, text, {
         accountId: accountId ?? undefined,
-        replyToId: replyToId ?? undefined,
-      })),
-    }) as const,
-  sendMedia: async ({ cfg, to, text, mediaUrl, mediaLocalRoots, accountId, replyToId, deps }) =>
-    ({
-      channel: "imessage",
-      ...(await resolveIMessageSender(deps)(to, text, {
-        config: cfg,
+      }),
+    ),
+  sendMedia: async ({ to, text, mediaUrl, mediaLocalRoots, mediaReadFile, accountId, deps }) =>
+    withIMessageChannel(
+      await resolveIMessageSender(deps)(to, text, {
         mediaUrl,
         mediaLocalRoots,
-        maxBytes: resolveIMessageMaxBytes(cfg),
+        mediaReadFile,
         accountId: accountId ?? undefined,
-        replyToId: replyToId ?? undefined,
-      })),
-    }) as const,
+      }),
+    ),
 };
diff --git a/src/infra/heartbeat-runner.test-channel-plugins.ts b/test/helpers/infra/heartbeat-runner-channel-plugins.ts
similarity index 92%
rename from src/infra/heartbeat-runner.test-channel-plugins.ts
rename to test/helpers/infra/heartbeat-runner-channel-plugins.ts
index fa7fbce2ddc..6304056c58e 100644
--- a/src/infra/heartbeat-runner.test-channel-plugins.ts
+++ b/test/helpers/infra/heartbeat-runner-channel-plugins.ts
@@ -2,9 +2,12 @@ import type {
   ChannelId,
   ChannelOutboundAdapter,
   ChannelPlugin,
-} from "../channels/plugins/types.js";
-import { createOutboundTestPlugin } from "../test-utils/channel-plugins.js";
-import { resolveOutboundSendDep, type OutboundSendDeps } from "./outbound/send-deps.js";
+} from "../../../src/channels/plugins/types.js";
+import {
+  resolveOutboundSendDep,
+  type OutboundSendDeps,
+} from "../../../src/infra/outbound/send-deps.js";
+import { createOutboundTestPlugin } from "../../../src/test-utils/channel-plugins.js";
 
 type HeartbeatSendChannelId = "slack" | "telegram" | "whatsapp";
 type HeartbeatSendFn = (