diff --git a/extensions/whatsapp/src/channel-react-action.test.ts b/extensions/whatsapp/src/channel-react-action.test.ts
index 17297f0c4af1..c49c259b2ec3 100644
--- a/extensions/whatsapp/src/channel-react-action.test.ts
+++ b/extensions/whatsapp/src/channel-react-action.test.ts
@@ -150,6 +150,43 @@ describe("whatsapp react action messageId resolution", () => {
     });
   });
 
+  it("uses toolContext current chat for same-chat upload-file", async () => {
+    const mediaReadFile = vi.fn(async () => Buffer.from("media"));
+
+    await handleWhatsAppMessageAction({
+      action: "upload-file",
+      params: {
+        filePath: "/tmp/pic.png",
+        caption: "picture caption",
+      },
+      cfg: baseCfg,
+      accountId: "default",
+      mediaLocalRoots: ["/tmp"],
+      mediaReadFile,
+      toolContext: {
+        currentChannelId: "whatsapp:+1555",
+        currentChannelProvider: "whatsapp",
+        currentMessageId: "ctx-msg-42",
+      },
+    });
+
+    expect(hoisted.resolveAuthorizedWhatsAppOutboundTarget).toHaveBeenCalledWith({
+      cfg: baseCfg,
+      chatJid: "+1555",
+      accountId: "default",
+      actionLabel: "upload-file",
+    });
+    expect(hoisted.sendMessageWhatsApp).toHaveBeenCalledWith(
+      "+1555",
+      "picture caption",
+      expect.objectContaining({
+        accountId: "default",
+        mediaReadFile,
+        mediaUrl: "/tmp/pic.png",
+      }),
+    );
+  });
+
   it("does not send upload-file when target authorization fails", async () => {
     hoisted.resolveAuthorizedWhatsAppOutboundTarget.mockImplementationOnce(() => {
       throw new Error("WhatsApp upload-file blocked");
@@ -286,6 +323,33 @@ describe("whatsapp react action messageId resolution", () => {
     );
   });
 
+  it("falls back to toolContext current chat for same-chat reactions", async () => {
+    await handleWhatsAppMessageAction({
+      action: "react",
+      params: { emoji: "❤️" },
+      cfg: baseCfg,
+      accountId: "default",
+      toolContext: {
+        currentChannelId: "whatsapp:+1555",
+        currentChannelProvider: "whatsapp",
+        currentMessageId: "ctx-msg-42",
+      },
+    });
+    expect(hoisted.handleWhatsAppAction).toHaveBeenCalledWith(
+      {
+        action: "react",
+        chatJid: "+1555",
+        messageId: "ctx-msg-42",
+        emoji: "❤️",
+        remove: undefined,
+        participant: undefined,
+        accountId: "default",
+        fromMe: undefined,
+      },
+      baseCfg,
+    );
+  });
+
   it("converts numeric toolContext messageId to string", async () => {
     await handleWhatsAppMessageAction({
       action: "react",
diff --git a/extensions/whatsapp/src/channel-react-action.ts b/extensions/whatsapp/src/channel-react-action.ts
index 36e3f154db77..161938e74046 100644
--- a/extensions/whatsapp/src/channel-react-action.ts
+++ b/extensions/whatsapp/src/channel-react-action.ts
@@ -76,6 +76,21 @@ function hasUploadFileBufferPayload(args: Record<string, unknown>): boolean {
   return readStringParam(args, "buffer", { trim: false }) !== undefined;
 }
 
+function readWhatsAppActionChatJid(params: WhatsAppMessageActionParams): string | undefined {
+  const explicit =
+    readStringParam(params.params, "chatJid") ?? readStringParam(params.params, "to");
+  if (explicit) {
+    return explicit;
+  }
+  if (
+    params.toolContext?.currentChannelProvider !== WHATSAPP_CHANNEL ||
+    !params.toolContext.currentChannelId
+  ) {
+    return undefined;
+  }
+  return normalizeWhatsAppTarget(params.toolContext.currentChannelId) ?? undefined;
+}
+
 function extractBase64Payload(encoded: string): string {
   const match = /^data:[^;]+;base64,(.*)$/i.exec(encoded.trim());
   return match ? match[1] : encoded;
@@ -134,7 +149,8 @@ async function handleWhatsAppUploadFileAction(params: WhatsAppMessageActionParam
       "WhatsApp upload-file requires media, mediaUrl, filePath, path, fileUrl, or buffer.",
     );
   }
-  const to = readStringParam(params.params, "to", { required: true });
+  const to =
+    readWhatsAppActionChatJid(params) ?? readStringParam(params.params, "to", { required: true });
   const resolved = resolveAuthorizedWhatsAppOutboundTarget({
     cfg: params.cfg,
     chatJid: to,
@@ -188,8 +204,7 @@ export async function handleWhatsAppMessageAction(params: WhatsAppMessageActionP
     throw new Error(`Action ${params.action} is not supported for provider ${WHATSAPP_CHANNEL}.`);
   }
   const isWhatsAppSource = params.toolContext?.currentChannelProvider === WHATSAPP_CHANNEL;
-  const explicitTarget =
-    readStringParam(params.params, "chatJid") ?? readStringParam(params.params, "to");
+  const explicitTarget = readWhatsAppActionChatJid(params);
   const normalizedTarget = explicitTarget ? normalizeWhatsAppTarget(explicitTarget) : null;
   const normalizedCurrent =
     isWhatsAppSource && params.toolContext?.currentChannelId
@@ -232,7 +247,7 @@ export async function handleWhatsAppMessageAction(params: WhatsAppMessageActionP
     {
       action: "react",
       chatJid:
-        readStringParam(params.params, "chatJid") ??
+        readWhatsAppActionChatJid(params) ??
         readStringParam(params.params, "to", { required: true }),
       messageId,
       emoji,