diff --git a/src/channels/plugins/actions/actions.test.ts b/src/channels/plugins/actions/actions.test.ts
index 1b33f41377c..de9aa4c4e18 100644
--- a/src/channels/plugins/actions/actions.test.ts
+++ b/src/channels/plugins/actions/actions.test.ts
@@ -526,4 +526,71 @@ describe("slack actions adapter", () => {
       limit: 2,
     });
   });
+
+  it("forwards blocks JSON for send", async () => {
+    const cfg = { channels: { slack: { botToken: "tok" } } } as OpenClawConfig;
+    const actions = createSlackActions("slack");
+
+    await actions.handleAction?.({
+      channel: "slack",
+      action: "send",
+      cfg,
+      params: {
+        to: "channel:C1",
+        message: "",
+        blocks: JSON.stringify([{ type: "divider" }]),
+      },
+    });
+
+    const [params] = handleSlackAction.mock.calls[0] ?? [];
+    expect(params).toMatchObject({
+      action: "sendMessage",
+      to: "channel:C1",
+      content: "",
+      blocks: [{ type: "divider" }],
+    });
+  });
+
+  it("forwards blocks arrays for send", async () => {
+    const cfg = { channels: { slack: { botToken: "tok" } } } as OpenClawConfig;
+    const actions = createSlackActions("slack");
+
+    await actions.handleAction?.({
+      channel: "slack",
+      action: "send",
+      cfg,
+      params: {
+        to: "channel:C1",
+        message: "",
+        blocks: [{ type: "section", text: { type: "mrkdwn", text: "hi" } }],
+      },
+    });
+
+    const [params] = handleSlackAction.mock.calls[0] ?? [];
+    expect(params).toMatchObject({
+      action: "sendMessage",
+      to: "channel:C1",
+      content: "",
+      blocks: [{ type: "section", text: { type: "mrkdwn", text: "hi" } }],
+    });
+  });
+
+  it("rejects invalid blocks JSON for send", async () => {
+    const cfg = { channels: { slack: { botToken: "tok" } } } as OpenClawConfig;
+    const actions = createSlackActions("slack");
+
+    await expect(
+      actions.handleAction?.({
+        channel: "slack",
+        action: "send",
+        cfg,
+        params: {
+          to: "channel:C1",
+          message: "",
+          blocks: "{bad-json",
+        },
+      }),
+    ).rejects.toThrow(/blocks must be valid JSON/i);
+    expect(handleSlackAction).not.toHaveBeenCalled();
+  });
 });
diff --git a/src/plugin-sdk/slack-message-actions.ts b/src/plugin-sdk/slack-message-actions.ts
index a98557d2c47..522aab3398a 100644
--- a/src/plugin-sdk/slack-message-actions.ts
+++ b/src/plugin-sdk/slack-message-actions.ts
@@ -8,6 +8,27 @@ type SlackActionInvoke = (
   toolContext?: ChannelMessageActionContext["toolContext"],
 ) => Promise<AgentToolResult<unknown>>;
 
+function readSlackBlocksParam(actionParams: Record<string, unknown>) {
+  const raw = actionParams.blocks;
+  if (raw == null) {
+    return undefined;
+  }
+  const parsed =
+    typeof raw === "string"
+      ? (() => {
+          try {
+            return JSON.parse(raw);
+          } catch {
+            throw new Error("blocks must be valid JSON");
+          }
+        })()
+      : raw;
+  if (!Array.isArray(parsed)) {
+    throw new Error("blocks must be an array");
+  }
+  return parsed as Record<string, unknown>[];
+}
+
 export async function handleSlackMessageAction(params: {
   providerId: string;
   ctx: ChannelMessageActionContext;
@@ -28,18 +49,23 @@ export async function handleSlackMessageAction(params: {
   if (action === "send") {
     const to = readStringParam(actionParams, "to", { required: true });
     const content = readStringParam(actionParams, "message", {
-      required: true,
+      required: false,
       allowEmpty: true,
     });
     const mediaUrl = readStringParam(actionParams, "media", { trim: false });
+    const blocks = readSlackBlocksParam(actionParams);
+    if (!content && !mediaUrl && !blocks) {
+      throw new Error("Slack send requires message, blocks, or media.");
+    }
     const threadId = readStringParam(actionParams, "threadId");
     const replyTo = readStringParam(actionParams, "replyTo");
     return await invoke(
       {
         action: "sendMessage",
         to,
-        content,
+        content: content ?? "",
         mediaUrl: mediaUrl ?? undefined,
+        blocks,
         accountId,
         threadTs: threadId ?? replyTo ?? undefined,
       },