diff --git a/extensions/zalo/src/channel.sendpayload.test.ts b/extensions/zalo/src/channel.sendpayload.test.ts
new file mode 100644
index 00000000000..5bac81dc54e
--- /dev/null
+++ b/extensions/zalo/src/channel.sendpayload.test.ts
@@ -0,0 +1,102 @@
+import type { ReplyPayload } from "openclaw/plugin-sdk";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { zaloPlugin } from "./channel.js";
+
+vi.mock("./send.js", () => ({
+  sendMessageZalo: vi.fn().mockResolvedValue({ ok: true, messageId: "zl-1" }),
+}));
+
+function baseCtx(payload: ReplyPayload) {
+  return {
+    cfg: {},
+    to: "123456789",
+    text: "",
+    payload,
+  };
+}
+
+describe("zaloPlugin outbound sendPayload", () => {
+  let mockedSend: ReturnType<typeof vi.mocked<(typeof import("./send.js"))["sendMessageZalo"]>>;
+
+  beforeEach(async () => {
+    const mod = await import("./send.js");
+    mockedSend = vi.mocked(mod.sendMessageZalo);
+    mockedSend.mockClear();
+    mockedSend.mockResolvedValue({ ok: true, messageId: "zl-1" });
+  });
+
+  it("text-only delegates to sendText", async () => {
+    mockedSend.mockResolvedValue({ ok: true, messageId: "zl-t1" });
+
+    const result = await zaloPlugin.outbound!.sendPayload!(baseCtx({ text: "hello" }));
+
+    expect(mockedSend).toHaveBeenCalledWith("123456789", "hello", expect.any(Object));
+    expect(result).toMatchObject({ channel: "zalo", messageId: "zl-t1" });
+  });
+
+  it("single media delegates to sendMedia", async () => {
+    mockedSend.mockResolvedValue({ ok: true, messageId: "zl-m1" });
+
+    const result = await zaloPlugin.outbound!.sendPayload!(
+      baseCtx({ text: "cap", mediaUrl: "https://example.com/a.jpg" }),
+    );
+
+    expect(mockedSend).toHaveBeenCalledWith(
+      "123456789",
+      "cap",
+      expect.objectContaining({ mediaUrl: "https://example.com/a.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "zalo" });
+  });
+
+  it("multi-media iterates URLs with caption on first", async () => {
+    mockedSend
+      .mockResolvedValueOnce({ ok: true, messageId: "zl-1" })
+      .mockResolvedValueOnce({ ok: true, messageId: "zl-2" });
+
+    const result = await zaloPlugin.outbound!.sendPayload!(
+      baseCtx({
+        text: "caption",
+        mediaUrls: ["https://example.com/1.jpg", "https://example.com/2.jpg"],
+      }),
+    );
+
+    expect(mockedSend).toHaveBeenCalledTimes(2);
+    expect(mockedSend).toHaveBeenNthCalledWith(
+      1,
+      "123456789",
+      "caption",
+      expect.objectContaining({ mediaUrl: "https://example.com/1.jpg" }),
+    );
+    expect(mockedSend).toHaveBeenNthCalledWith(
+      2,
+      "123456789",
+      "",
+      expect.objectContaining({ mediaUrl: "https://example.com/2.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "zalo", messageId: "zl-2" });
+  });
+
+  it("empty payload returns no-op", async () => {
+    const result = await zaloPlugin.outbound!.sendPayload!(baseCtx({}));
+
+    expect(mockedSend).not.toHaveBeenCalled();
+    expect(result).toEqual({ channel: "zalo", messageId: "" });
+  });
+
+  it("chunking splits long text", async () => {
+    mockedSend
+      .mockResolvedValueOnce({ ok: true, messageId: "zl-c1" })
+      .mockResolvedValueOnce({ ok: true, messageId: "zl-c2" });
+
+    const longText = "a".repeat(3000);
+    const result = await zaloPlugin.outbound!.sendPayload!(baseCtx({ text: longText }));
+
+    // textChunkLimit is 2000 with chunkTextForOutbound, so it should split
+    expect(mockedSend.mock.calls.length).toBeGreaterThanOrEqual(2);
+    for (const call of mockedSend.mock.calls) {
+      expect((call[1] as string).length).toBeLessThanOrEqual(2000);
+    }
+    expect(result).toMatchObject({ channel: "zalo" });
+  });
+});
diff --git a/extensions/zalo/src/channel.ts b/extensions/zalo/src/channel.ts
index 4a37f1a5e0f..1bd9d3a401c 100644
--- a/extensions/zalo/src/channel.ts
+++ b/extensions/zalo/src/channel.ts
@@ -303,15 +303,19 @@ export const zaloPlugin: ChannelPlugin<ResolvedZaloAccount> = {
     chunkerMode: "text",
     textChunkLimit: 2000,
     sendPayload: async (ctx) => {
+      const text = ctx.payload.text ?? "";
       const urls = ctx.payload.mediaUrls?.length
         ? ctx.payload.mediaUrls
         : ctx.payload.mediaUrl
           ? [ctx.payload.mediaUrl]
           : [];
+      if (!text && urls.length === 0) {
+        return { channel: "zalo", messageId: "" };
+      }
       if (urls.length > 0) {
         let lastResult = await zaloPlugin.outbound!.sendMedia!({
           ...ctx,
-          text: ctx.payload.text ?? "",
+          text,
           mediaUrl: urls[0],
         });
         for (let i = 1; i < urls.length; i++) {
@@ -323,7 +327,14 @@ export const zaloPlugin: ChannelPlugin<ResolvedZaloAccount> = {
         }
         return lastResult;
       }
-      return zaloPlugin.outbound!.sendText!({ ...ctx, text: ctx.payload.text ?? "" });
+      const outbound = zaloPlugin.outbound!;
+      const limit = outbound.textChunkLimit;
+      const chunks = limit && outbound.chunker ? outbound.chunker(text, limit) : [text];
+      let lastResult: Awaited<ReturnType<NonNullable<typeof outbound.sendText>>>;
+      for (const chunk of chunks) {
+        lastResult = await outbound.sendText!({ ...ctx, text: chunk });
+      }
+      return lastResult!;
     },
     sendText: async ({ to, text, accountId, cfg }) => {
       const result = await sendMessageZalo(to, text, {
diff --git a/extensions/zalouser/src/channel.sendpayload.test.ts b/extensions/zalouser/src/channel.sendpayload.test.ts
new file mode 100644
index 00000000000..07a246b4957
--- /dev/null
+++ b/extensions/zalouser/src/channel.sendpayload.test.ts
@@ -0,0 +1,116 @@
+import type { ReplyPayload } from "openclaw/plugin-sdk";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { zalouserPlugin } from "./channel.js";
+
+vi.mock("./send.js", () => ({
+  sendMessageZalouser: vi.fn().mockResolvedValue({ ok: true, messageId: "zlu-1" }),
+}));
+
+vi.mock("./accounts.js", async (importOriginal) => {
+  const actual = (await importOriginal()) as Record<string, unknown>;
+  return {
+    ...actual,
+    resolveZalouserAccountSync: () => ({
+      accountId: "default",
+      profile: "default",
+      name: "test",
+      enabled: true,
+      config: {},
+    }),
+  };
+});
+
+function baseCtx(payload: ReplyPayload) {
+  return {
+    cfg: {},
+    to: "987654321",
+    text: "",
+    payload,
+  };
+}
+
+describe("zalouserPlugin outbound sendPayload", () => {
+  let mockedSend: ReturnType<typeof vi.mocked<(typeof import("./send.js"))["sendMessageZalouser"]>>;
+
+  beforeEach(async () => {
+    const mod = await import("./send.js");
+    mockedSend = vi.mocked(mod.sendMessageZalouser);
+    mockedSend.mockClear();
+    mockedSend.mockResolvedValue({ ok: true, messageId: "zlu-1" });
+  });
+
+  it("text-only delegates to sendText", async () => {
+    mockedSend.mockResolvedValue({ ok: true, messageId: "zlu-t1" });
+
+    const result = await zalouserPlugin.outbound!.sendPayload!(baseCtx({ text: "hello" }));
+
+    expect(mockedSend).toHaveBeenCalledWith("987654321", "hello", expect.any(Object));
+    expect(result).toMatchObject({ channel: "zalouser", messageId: "zlu-t1" });
+  });
+
+  it("single media delegates to sendMedia", async () => {
+    mockedSend.mockResolvedValue({ ok: true, messageId: "zlu-m1" });
+
+    const result = await zalouserPlugin.outbound!.sendPayload!(
+      baseCtx({ text: "cap", mediaUrl: "https://example.com/a.jpg" }),
+    );
+
+    expect(mockedSend).toHaveBeenCalledWith(
+      "987654321",
+      "cap",
+      expect.objectContaining({ mediaUrl: "https://example.com/a.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "zalouser" });
+  });
+
+  it("multi-media iterates URLs with caption on first", async () => {
+    mockedSend
+      .mockResolvedValueOnce({ ok: true, messageId: "zlu-1" })
+      .mockResolvedValueOnce({ ok: true, messageId: "zlu-2" });
+
+    const result = await zalouserPlugin.outbound!.sendPayload!(
+      baseCtx({
+        text: "caption",
+        mediaUrls: ["https://example.com/1.jpg", "https://example.com/2.jpg"],
+      }),
+    );
+
+    expect(mockedSend).toHaveBeenCalledTimes(2);
+    expect(mockedSend).toHaveBeenNthCalledWith(
+      1,
+      "987654321",
+      "caption",
+      expect.objectContaining({ mediaUrl: "https://example.com/1.jpg" }),
+    );
+    expect(mockedSend).toHaveBeenNthCalledWith(
+      2,
+      "987654321",
+      "",
+      expect.objectContaining({ mediaUrl: "https://example.com/2.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "zalouser", messageId: "zlu-2" });
+  });
+
+  it("empty payload returns no-op", async () => {
+    const result = await zalouserPlugin.outbound!.sendPayload!(baseCtx({}));
+
+    expect(mockedSend).not.toHaveBeenCalled();
+    expect(result).toEqual({ channel: "zalouser", messageId: "" });
+  });
+
+  it("chunking splits long text", async () => {
+    mockedSend
+      .mockResolvedValueOnce({ ok: true, messageId: "zlu-c1" })
+      .mockResolvedValueOnce({ ok: true, messageId: "zlu-c2" });
+
+    const longText = "a".repeat(3000);
+    const result = await zalouserPlugin.outbound!.sendPayload!(baseCtx({ text: longText }));
+
+    // textChunkLimit is 2000 with chunkTextForOutbound, so it should split
+    expect(mockedSend.mock.calls.length).toBeGreaterThanOrEqual(2);
+    for (const call of mockedSend.mock.calls) {
+      expect((call[1] as string).length).toBeLessThanOrEqual(2000);
+    }
+    expect(result).toMatchObject({ channel: "zalouser" });
+  });
+});
diff --git a/extensions/zalouser/src/channel.ts b/extensions/zalouser/src/channel.ts
index 48c49646509..1b711074d65 100644
--- a/extensions/zalouser/src/channel.ts
+++ b/extensions/zalouser/src/channel.ts
@@ -519,15 +519,19 @@ export const zalouserPlugin: ChannelPlugin<ResolvedZalouserAccount> = {
     chunkerMode: "text",
     textChunkLimit: 2000,
     sendPayload: async (ctx) => {
+      const text = ctx.payload.text ?? "";
       const urls = ctx.payload.mediaUrls?.length
         ? ctx.payload.mediaUrls
         : ctx.payload.mediaUrl
           ? [ctx.payload.mediaUrl]
           : [];
+      if (!text && urls.length === 0) {
+        return { channel: "zalouser", messageId: "" };
+      }
       if (urls.length > 0) {
         let lastResult = await zalouserPlugin.outbound!.sendMedia!({
           ...ctx,
-          text: ctx.payload.text ?? "",
+          text,
           mediaUrl: urls[0],
         });
         for (let i = 1; i < urls.length; i++) {
@@ -539,7 +543,14 @@ export const zalouserPlugin: ChannelPlugin<ResolvedZalouserAccount> = {
         }
         return lastResult;
       }
-      return zalouserPlugin.outbound!.sendText!({ ...ctx, text: ctx.payload.text ?? "" });
+      const outbound = zalouserPlugin.outbound!;
+      const limit = outbound.textChunkLimit;
+      const chunks = limit && outbound.chunker ? outbound.chunker(text, limit) : [text];
+      let lastResult: Awaited<ReturnType<NonNullable<typeof outbound.sendText>>>;
+      for (const chunk of chunks) {
+        lastResult = await outbound.sendText!({ ...ctx, text: chunk });
+      }
+      return lastResult!;
     },
     sendText: async ({ to, text, accountId, cfg }) => {
       const account = resolveZalouserAccountSync({ cfg: cfg, accountId });
diff --git a/src/channels/plugins/outbound/direct-text-media.sendpayload.test.ts b/src/channels/plugins/outbound/direct-text-media.sendpayload.test.ts
new file mode 100644
index 00000000000..0e5c2ba01db
--- /dev/null
+++ b/src/channels/plugins/outbound/direct-text-media.sendpayload.test.ts
@@ -0,0 +1,117 @@
+import { describe, expect, it, vi } from "vitest";
+import type { ReplyPayload } from "../../../auto-reply/types.js";
+import { createDirectTextMediaOutbound } from "./direct-text-media.js";
+
+function makeOutbound() {
+  const sendFn = vi.fn().mockResolvedValue({ messageId: "m1" });
+  const outbound = createDirectTextMediaOutbound({
+    channel: "imessage",
+    resolveSender: () => sendFn,
+    resolveMaxBytes: () => undefined,
+    buildTextOptions: (opts) => opts as never,
+    buildMediaOptions: (opts) => opts as never,
+  });
+  return { outbound, sendFn };
+}
+
+function baseCtx(payload: ReplyPayload) {
+  return {
+    cfg: {},
+    to: "user1",
+    text: "",
+    payload,
+  };
+}
+
+describe("createDirectTextMediaOutbound sendPayload", () => {
+  it("text-only delegates to sendText", async () => {
+    const { outbound, sendFn } = makeOutbound();
+    const result = await outbound.sendPayload!(baseCtx({ text: "hello" }));
+
+    expect(sendFn).toHaveBeenCalledTimes(1);
+    expect(sendFn).toHaveBeenCalledWith("user1", "hello", expect.any(Object));
+    expect(result).toMatchObject({ channel: "imessage", messageId: "m1" });
+  });
+
+  it("single media delegates to sendMedia", async () => {
+    const { outbound, sendFn } = makeOutbound();
+    const result = await outbound.sendPayload!(
+      baseCtx({ text: "cap", mediaUrl: "https://example.com/a.jpg" }),
+    );
+
+    expect(sendFn).toHaveBeenCalledTimes(1);
+    expect(sendFn).toHaveBeenCalledWith(
+      "user1",
+      "cap",
+      expect.objectContaining({ mediaUrl: "https://example.com/a.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "imessage", messageId: "m1" });
+  });
+
+  it("multi-media iterates URLs with caption on first", async () => {
+    const sendFn = vi
+      .fn()
+      .mockResolvedValueOnce({ messageId: "m1" })
+      .mockResolvedValueOnce({ messageId: "m2" });
+    const outbound = createDirectTextMediaOutbound({
+      channel: "imessage",
+      resolveSender: () => sendFn,
+      resolveMaxBytes: () => undefined,
+      buildTextOptions: (opts) => opts as never,
+      buildMediaOptions: (opts) => opts as never,
+    });
+    const result = await outbound.sendPayload!(
+      baseCtx({
+        text: "caption",
+        mediaUrls: ["https://example.com/1.jpg", "https://example.com/2.jpg"],
+      }),
+    );
+
+    expect(sendFn).toHaveBeenCalledTimes(2);
+    expect(sendFn).toHaveBeenNthCalledWith(
+      1,
+      "user1",
+      "caption",
+      expect.objectContaining({ mediaUrl: "https://example.com/1.jpg" }),
+    );
+    expect(sendFn).toHaveBeenNthCalledWith(
+      2,
+      "user1",
+      "",
+      expect.objectContaining({ mediaUrl: "https://example.com/2.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "imessage", messageId: "m2" });
+  });
+
+  it("empty payload returns no-op", async () => {
+    const { outbound, sendFn } = makeOutbound();
+    const result = await outbound.sendPayload!(baseCtx({}));
+
+    expect(sendFn).not.toHaveBeenCalled();
+    expect(result).toEqual({ channel: "imessage", messageId: "" });
+  });
+
+  it("chunking splits long text", async () => {
+    const sendFn = vi
+      .fn()
+      .mockResolvedValueOnce({ messageId: "c1" })
+      .mockResolvedValueOnce({ messageId: "c2" });
+    const outbound = createDirectTextMediaOutbound({
+      channel: "signal",
+      resolveSender: () => sendFn,
+      resolveMaxBytes: () => undefined,
+      buildTextOptions: (opts) => opts as never,
+      buildMediaOptions: (opts) => opts as never,
+    });
+    // textChunkLimit is 4000; generate text exceeding that
+    const longText = "a".repeat(5000);
+    const result = await outbound.sendPayload!(baseCtx({ text: longText }));
+
+    expect(sendFn.mock.calls.length).toBeGreaterThanOrEqual(2);
+    // Each chunk should be within the limit
+    for (const call of sendFn.mock.calls) {
+      expect((call[1] as string).length).toBeLessThanOrEqual(4000);
+    }
+    expect(result).toMatchObject({ channel: "signal" });
+  });
+});
diff --git a/src/channels/plugins/outbound/direct-text-media.ts b/src/channels/plugins/outbound/direct-text-media.ts
index 7b15d34913a..32e4ed5e5aa 100644
--- a/src/channels/plugins/outbound/direct-text-media.ts
+++ b/src/channels/plugins/outbound/direct-text-media.ts
@@ -92,15 +92,19 @@ export function createDirectTextMediaOutbound<
     chunkerMode: "text",
     textChunkLimit: 4000,
     sendPayload: async (ctx) => {
+      const text = ctx.payload.text ?? "";
       const urls = ctx.payload.mediaUrls?.length
         ? ctx.payload.mediaUrls
         : ctx.payload.mediaUrl
           ? [ctx.payload.mediaUrl]
           : [];
+      if (!text && urls.length === 0) {
+        return { channel: params.channel, messageId: "" };
+      }
       if (urls.length > 0) {
         let lastResult = await outbound.sendMedia!({
           ...ctx,
-          text: ctx.payload.text ?? "",
+          text,
           mediaUrl: urls[0],
         });
         for (let i = 1; i < urls.length; i++) {
@@ -112,7 +116,13 @@ export function createDirectTextMediaOutbound<
         }
         return lastResult;
       }
-      return outbound.sendText!({ ...ctx, text: ctx.payload.text ?? "" });
+      const limit = outbound.textChunkLimit;
+      const chunks = limit && outbound.chunker ? outbound.chunker(text, limit) : [text];
+      let lastResult: Awaited<ReturnType<NonNullable<typeof outbound.sendText>>>;
+      for (const chunk of chunks) {
+        lastResult = await outbound.sendText!({ ...ctx, text: chunk });
+      }
+      return lastResult!;
     },
     sendText: async ({ cfg, to, text, accountId, deps, replyToId }) => {
       return await sendDirect({
diff --git a/src/channels/plugins/outbound/discord.sendpayload.test.ts b/src/channels/plugins/outbound/discord.sendpayload.test.ts
new file mode 100644
index 00000000000..07c821d6e79
--- /dev/null
+++ b/src/channels/plugins/outbound/discord.sendpayload.test.ts
@@ -0,0 +1,98 @@
+import { describe, expect, it, vi } from "vitest";
+import type { ReplyPayload } from "../../../auto-reply/types.js";
+import { discordOutbound } from "./discord.js";
+
+function baseCtx(payload: ReplyPayload) {
+  return {
+    cfg: {},
+    to: "channel:123456",
+    text: "",
+    payload,
+    deps: {
+      sendDiscord: vi.fn().mockResolvedValue({ messageId: "dc-1", channelId: "123456" }),
+    },
+  };
+}
+
+describe("discordOutbound sendPayload", () => {
+  it("text-only delegates to sendText", async () => {
+    const ctx = baseCtx({ text: "hello" });
+    const result = await discordOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendDiscord).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendDiscord).toHaveBeenCalledWith(
+      "channel:123456",
+      "hello",
+      expect.any(Object),
+    );
+    expect(result).toMatchObject({ channel: "discord" });
+  });
+
+  it("single media delegates to sendMedia", async () => {
+    const ctx = baseCtx({ text: "cap", mediaUrl: "https://example.com/a.jpg" });
+    const result = await discordOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendDiscord).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendDiscord).toHaveBeenCalledWith(
+      "channel:123456",
+      "cap",
+      expect.objectContaining({ mediaUrl: "https://example.com/a.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "discord" });
+  });
+
+  it("multi-media iterates URLs with caption on first", async () => {
+    const sendDiscord = vi
+      .fn()
+      .mockResolvedValueOnce({ messageId: "dc-1", channelId: "123456" })
+      .mockResolvedValueOnce({ messageId: "dc-2", channelId: "123456" });
+    const ctx = {
+      cfg: {},
+      to: "channel:123456",
+      text: "",
+      payload: {
+        text: "caption",
+        mediaUrls: ["https://example.com/1.jpg", "https://example.com/2.jpg"],
+      } as ReplyPayload,
+      deps: { sendDiscord },
+    };
+    const result = await discordOutbound.sendPayload!(ctx);
+
+    expect(sendDiscord).toHaveBeenCalledTimes(2);
+    expect(sendDiscord).toHaveBeenNthCalledWith(
+      1,
+      "channel:123456",
+      "caption",
+      expect.objectContaining({ mediaUrl: "https://example.com/1.jpg" }),
+    );
+    expect(sendDiscord).toHaveBeenNthCalledWith(
+      2,
+      "channel:123456",
+      "",
+      expect.objectContaining({ mediaUrl: "https://example.com/2.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "discord", messageId: "dc-2" });
+  });
+
+  it("empty payload returns no-op", async () => {
+    const ctx = baseCtx({});
+    const result = await discordOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendDiscord).not.toHaveBeenCalled();
+    expect(result).toEqual({ channel: "discord", messageId: "" });
+  });
+
+  it("text exceeding chunk limit is sent as-is when chunker is null", async () => {
+    // Discord has chunker: null, so long text should be sent as a single message
+    const ctx = baseCtx({ text: "a".repeat(3000) });
+    const result = await discordOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendDiscord).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendDiscord).toHaveBeenCalledWith(
+      "channel:123456",
+      "a".repeat(3000),
+      expect.any(Object),
+    );
+    expect(result).toMatchObject({ channel: "discord" });
+  });
+});
diff --git a/src/channels/plugins/outbound/discord.ts b/src/channels/plugins/outbound/discord.ts
index 891cbf4b432..9c416c590bb 100644
--- a/src/channels/plugins/outbound/discord.ts
+++ b/src/channels/plugins/outbound/discord.ts
@@ -81,15 +81,19 @@ export const discordOutbound: ChannelOutboundAdapter = {
   pollMaxOptions: 10,
   resolveTarget: ({ to }) => normalizeDiscordOutboundTarget(to),
   sendPayload: async (ctx) => {
+    const text = ctx.payload.text ?? "";
     const urls = ctx.payload.mediaUrls?.length
       ? ctx.payload.mediaUrls
       : ctx.payload.mediaUrl
         ? [ctx.payload.mediaUrl]
         : [];
+    if (!text && urls.length === 0) {
+      return { channel: "discord", messageId: "" };
+    }
     if (urls.length > 0) {
       let lastResult = await discordOutbound.sendMedia!({
         ...ctx,
-        text: ctx.payload.text ?? "",
+        text,
         mediaUrl: urls[0],
       });
       for (let i = 1; i < urls.length; i++) {
@@ -101,7 +105,13 @@ export const discordOutbound: ChannelOutboundAdapter = {
       }
       return lastResult;
     }
-    return discordOutbound.sendText!({ ...ctx, text: ctx.payload.text ?? "" });
+    const limit = discordOutbound.textChunkLimit;
+    const chunks = limit && discordOutbound.chunker ? discordOutbound.chunker(text, limit) : [text];
+    let lastResult: Awaited<ReturnType<NonNullable<typeof discordOutbound.sendText>>>;
+    for (const chunk of chunks) {
+      lastResult = await discordOutbound.sendText!({ ...ctx, text: chunk });
+    }
+    return lastResult!;
   },
   sendText: async ({ to, text, accountId, deps, replyToId, threadId, identity, silent }) => {
     if (!silent) {
diff --git a/src/channels/plugins/outbound/slack.sendpayload.test.ts b/src/channels/plugins/outbound/slack.sendpayload.test.ts
new file mode 100644
index 00000000000..c6df264df12
--- /dev/null
+++ b/src/channels/plugins/outbound/slack.sendpayload.test.ts
@@ -0,0 +1,92 @@
+import { describe, expect, it, vi } from "vitest";
+import type { ReplyPayload } from "../../../auto-reply/types.js";
+import { slackOutbound } from "./slack.js";
+
+function baseCtx(payload: ReplyPayload) {
+  return {
+    cfg: {},
+    to: "C12345",
+    text: "",
+    payload,
+    deps: {
+      sendSlack: vi
+        .fn()
+        .mockResolvedValue({ messageId: "sl-1", channelId: "C12345", ts: "1234.5678" }),
+    },
+  };
+}
+
+describe("slackOutbound sendPayload", () => {
+  it("text-only delegates to sendText", async () => {
+    const ctx = baseCtx({ text: "hello" });
+    const result = await slackOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendSlack).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendSlack).toHaveBeenCalledWith("C12345", "hello", expect.any(Object));
+    expect(result).toMatchObject({ channel: "slack" });
+  });
+
+  it("single media delegates to sendMedia", async () => {
+    const ctx = baseCtx({ text: "cap", mediaUrl: "https://example.com/a.jpg" });
+    const result = await slackOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendSlack).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendSlack).toHaveBeenCalledWith(
+      "C12345",
+      "cap",
+      expect.objectContaining({ mediaUrl: "https://example.com/a.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "slack" });
+  });
+
+  it("multi-media iterates URLs with caption on first", async () => {
+    const sendSlack = vi
+      .fn()
+      .mockResolvedValueOnce({ messageId: "sl-1", channelId: "C12345" })
+      .mockResolvedValueOnce({ messageId: "sl-2", channelId: "C12345" });
+    const ctx = {
+      cfg: {},
+      to: "C12345",
+      text: "",
+      payload: {
+        text: "caption",
+        mediaUrls: ["https://example.com/1.jpg", "https://example.com/2.jpg"],
+      } as ReplyPayload,
+      deps: { sendSlack },
+    };
+    const result = await slackOutbound.sendPayload!(ctx);
+
+    expect(sendSlack).toHaveBeenCalledTimes(2);
+    expect(sendSlack).toHaveBeenNthCalledWith(
+      1,
+      "C12345",
+      "caption",
+      expect.objectContaining({ mediaUrl: "https://example.com/1.jpg" }),
+    );
+    expect(sendSlack).toHaveBeenNthCalledWith(
+      2,
+      "C12345",
+      "",
+      expect.objectContaining({ mediaUrl: "https://example.com/2.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "slack", messageId: "sl-2" });
+  });
+
+  it("empty payload returns no-op", async () => {
+    const ctx = baseCtx({});
+    const result = await slackOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendSlack).not.toHaveBeenCalled();
+    expect(result).toEqual({ channel: "slack", messageId: "" });
+  });
+
+  it("text exceeding chunk limit is sent as-is when chunker is null", async () => {
+    // Slack has chunker: null, so long text should be sent as a single message
+    const ctx = baseCtx({ text: "a".repeat(5000) });
+    const result = await slackOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendSlack).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendSlack).toHaveBeenCalledWith("C12345", "a".repeat(5000), expect.any(Object));
+    expect(result).toMatchObject({ channel: "slack" });
+  });
+});
diff --git a/src/channels/plugins/outbound/slack.ts b/src/channels/plugins/outbound/slack.ts
index 2bfc0f0a672..3828eaff3e1 100644
--- a/src/channels/plugins/outbound/slack.ts
+++ b/src/channels/plugins/outbound/slack.ts
@@ -94,15 +94,19 @@ export const slackOutbound: ChannelOutboundAdapter = {
   chunker: null,
   textChunkLimit: 4000,
   sendPayload: async (ctx) => {
+    const text = ctx.payload.text ?? "";
     const urls = ctx.payload.mediaUrls?.length
       ? ctx.payload.mediaUrls
       : ctx.payload.mediaUrl
         ? [ctx.payload.mediaUrl]
         : [];
+    if (!text && urls.length === 0) {
+      return { channel: "slack", messageId: "" };
+    }
     if (urls.length > 0) {
       let lastResult = await slackOutbound.sendMedia!({
         ...ctx,
-        text: ctx.payload.text ?? "",
+        text,
         mediaUrl: urls[0],
       });
       for (let i = 1; i < urls.length; i++) {
@@ -114,7 +118,13 @@ export const slackOutbound: ChannelOutboundAdapter = {
       }
       return lastResult;
     }
-    return slackOutbound.sendText!({ ...ctx, text: ctx.payload.text ?? "" });
+    const limit = slackOutbound.textChunkLimit;
+    const chunks = limit && slackOutbound.chunker ? slackOutbound.chunker(text, limit) : [text];
+    let lastResult: Awaited<ReturnType<NonNullable<typeof slackOutbound.sendText>>>;
+    for (const chunk of chunks) {
+      lastResult = await slackOutbound.sendText!({ ...ctx, text: chunk });
+    }
+    return lastResult!;
   },
   sendText: async ({ to, text, accountId, deps, replyToId, threadId, identity }) => {
     return await sendSlackOutboundMessage({
diff --git a/src/channels/plugins/outbound/whatsapp.sendpayload.test.ts b/src/channels/plugins/outbound/whatsapp.sendpayload.test.ts
new file mode 100644
index 00000000000..3eb6f7467dc
--- /dev/null
+++ b/src/channels/plugins/outbound/whatsapp.sendpayload.test.ts
@@ -0,0 +1,106 @@
+import { describe, expect, it, vi } from "vitest";
+import type { ReplyPayload } from "../../../auto-reply/types.js";
+import { whatsappOutbound } from "./whatsapp.js";
+
+function baseCtx(payload: ReplyPayload) {
+  return {
+    cfg: {},
+    to: "5511999999999@c.us",
+    text: "",
+    payload,
+    deps: {
+      sendWhatsApp: vi.fn().mockResolvedValue({ messageId: "wa-1" }),
+    },
+  };
+}
+
+describe("whatsappOutbound sendPayload", () => {
+  it("text-only delegates to sendText", async () => {
+    const ctx = baseCtx({ text: "hello" });
+    const result = await whatsappOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendWhatsApp).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendWhatsApp).toHaveBeenCalledWith(
+      "5511999999999@c.us",
+      "hello",
+      expect.any(Object),
+    );
+    expect(result).toMatchObject({ channel: "whatsapp", messageId: "wa-1" });
+  });
+
+  it("single media delegates to sendMedia", async () => {
+    const ctx = baseCtx({ text: "cap", mediaUrl: "https://example.com/a.jpg" });
+    const result = await whatsappOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendWhatsApp).toHaveBeenCalledTimes(1);
+    expect(ctx.deps.sendWhatsApp).toHaveBeenCalledWith(
+      "5511999999999@c.us",
+      "cap",
+      expect.objectContaining({ mediaUrl: "https://example.com/a.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "whatsapp" });
+  });
+
+  it("multi-media iterates URLs with caption on first", async () => {
+    const sendWhatsApp = vi
+      .fn()
+      .mockResolvedValueOnce({ messageId: "wa-1" })
+      .mockResolvedValueOnce({ messageId: "wa-2" });
+    const ctx = {
+      cfg: {},
+      to: "5511999999999@c.us",
+      text: "",
+      payload: {
+        text: "caption",
+        mediaUrls: ["https://example.com/1.jpg", "https://example.com/2.jpg"],
+      } as ReplyPayload,
+      deps: { sendWhatsApp },
+    };
+    const result = await whatsappOutbound.sendPayload!(ctx);
+
+    expect(sendWhatsApp).toHaveBeenCalledTimes(2);
+    expect(sendWhatsApp).toHaveBeenNthCalledWith(
+      1,
+      "5511999999999@c.us",
+      "caption",
+      expect.objectContaining({ mediaUrl: "https://example.com/1.jpg" }),
+    );
+    expect(sendWhatsApp).toHaveBeenNthCalledWith(
+      2,
+      "5511999999999@c.us",
+      "",
+      expect.objectContaining({ mediaUrl: "https://example.com/2.jpg" }),
+    );
+    expect(result).toMatchObject({ channel: "whatsapp", messageId: "wa-2" });
+  });
+
+  it("empty payload returns no-op", async () => {
+    const ctx = baseCtx({});
+    const result = await whatsappOutbound.sendPayload!(ctx);
+
+    expect(ctx.deps.sendWhatsApp).not.toHaveBeenCalled();
+    expect(result).toEqual({ channel: "whatsapp", messageId: "" });
+  });
+
+  it("chunking splits long text", async () => {
+    const sendWhatsApp = vi
+      .fn()
+      .mockResolvedValueOnce({ messageId: "wa-c1" })
+      .mockResolvedValueOnce({ messageId: "wa-c2" });
+    const longText = "a".repeat(5000);
+    const ctx = {
+      cfg: {},
+      to: "5511999999999@c.us",
+      text: "",
+      payload: { text: longText } as ReplyPayload,
+      deps: { sendWhatsApp },
+    };
+    const result = await whatsappOutbound.sendPayload!(ctx);
+
+    expect(sendWhatsApp.mock.calls.length).toBeGreaterThanOrEqual(2);
+    for (const call of sendWhatsApp.mock.calls) {
+      expect((call[1] as string).length).toBeLessThanOrEqual(4000);
+    }
+    expect(result).toMatchObject({ channel: "whatsapp" });
+  });
+});
diff --git a/src/channels/plugins/outbound/whatsapp.ts b/src/channels/plugins/outbound/whatsapp.ts
index db1c52a0a10..daa47e3324f 100644
--- a/src/channels/plugins/outbound/whatsapp.ts
+++ b/src/channels/plugins/outbound/whatsapp.ts
@@ -13,15 +13,19 @@ export const whatsappOutbound: ChannelOutboundAdapter = {
   resolveTarget: ({ to, allowFrom, mode }) =>
     resolveWhatsAppOutboundTarget({ to, allowFrom, mode }),
   sendPayload: async (ctx) => {
+    const text = ctx.payload.text ?? "";
     const urls = ctx.payload.mediaUrls?.length
       ? ctx.payload.mediaUrls
       : ctx.payload.mediaUrl
         ? [ctx.payload.mediaUrl]
         : [];
+    if (!text && urls.length === 0) {
+      return { channel: "whatsapp", messageId: "" };
+    }
     if (urls.length > 0) {
       let lastResult = await whatsappOutbound.sendMedia!({
         ...ctx,
-        text: ctx.payload.text ?? "",
+        text,
         mediaUrl: urls[0],
       });
       for (let i = 1; i < urls.length; i++) {
@@ -33,7 +37,14 @@ export const whatsappOutbound: ChannelOutboundAdapter = {
       }
       return lastResult;
     }
-    return whatsappOutbound.sendText!({ ...ctx, text: ctx.payload.text ?? "" });
+    const limit = whatsappOutbound.textChunkLimit;
+    const chunks =
+      limit && whatsappOutbound.chunker ? whatsappOutbound.chunker(text, limit) : [text];
+    let lastResult: Awaited<ReturnType<NonNullable<typeof whatsappOutbound.sendText>>>;
+    for (const chunk of chunks) {
+      lastResult = await whatsappOutbound.sendText!({ ...ctx, text: chunk });
+    }
+    return lastResult!;
   },
   sendText: async ({ to, text, accountId, deps, gifPlayback }) => {
     const send =