fix(telegram): set parse_mode for markdown messages

.changeset/fix-telegram-markdown-parse-mode.md

@@ -0,0 +1,5 @@
+---
+"@chat-adapter/telegram": patch
+---
+
+Set `parse_mode` to `"Markdown"` when posting messages with a `markdown` field, not only for card messages

packages/adapter-telegram/src/index.test.ts

@@ -943,6 +943,38 @@ describe("TelegramAdapter", () => {
     expect(sendMessageBody.text).toBe("raw id message");
   });
 
+  it("sets parse_mode for markdown messages", async () => {
+    mockFetch
+      .mockResolvedValueOnce(
+        telegramOk({
+          id: 999,
+          is_bot: true,
+          first_name: "Bot",
+          username: "mybot",
+        })
+      )
+      .mockResolvedValueOnce(telegramOk(sampleMessage()));
+
+    const adapter = createTelegramAdapter({
+      botToken: "token",
+      mode: "webhook",
+      logger: mockLogger,
+      userName: "mybot",
+    });
+
+    await adapter.initialize(createMockChat());
+
+    await adapter.postMessage("telegram:123", {
+      markdown: "**bold** and _italic_",
+    });
+
+    const sendMessageBody = JSON.parse(
+      String((mockFetch.mock.calls[1]?.[1] as RequestInit).body)
+    ) as { parse_mode?: string };
+
+    expect(sendMessageBody.parse_mode).toBe("Markdown");
+  });
+
   it("posts cards with inline keyboard buttons", async () => {
     mockFetch
       .mockResolvedValueOnce(

packages/adapter-telegram/src/index.ts

@@ -556,7 +556,10 @@ export class TelegramAdapter
 
     const card = extractCard(message);
     const replyMarkup = card ? cardToTelegramInlineKeyboard(card) : undefined;
-    const parseMode = card ? TELEGRAM_MARKDOWN_PARSE_MODE : undefined;
+    const hasMarkdown =
+      typeof message === "object" && message !== null && "markdown" in message;
+    const parseMode =
+      card || hasMarkdown ? TELEGRAM_MARKDOWN_PARSE_MODE : undefined;
     const text = this.truncateMessage(
       convertEmojiPlaceholders(
         card
@@ -642,7 +645,10 @@ export class TelegramAdapter
 
     const card = extractCard(message);
     const replyMarkup = card ? cardToTelegramInlineKeyboard(card) : undefined;
-    const parseMode = card ? TELEGRAM_MARKDOWN_PARSE_MODE : undefined;
+    const hasMarkdown =
+      typeof message === "object" && message !== null && "markdown" in message;
+    const parseMode =
+      card || hasMarkdown ? TELEGRAM_MARKDOWN_PARSE_MODE : undefined;
     const text = this.truncateMessage(
       convertEmojiPlaceholders(
         card