From 1c61440ff3eb501231e39cc77ff802ad179ff17e Mon Sep 17 00:00:00 2001
From: SidQin-cyber <sidqin0410@gmail.com>
Date: Tue, 3 Mar 2026 00:48:54 +0800
Subject: [PATCH] fix(slack): apply mrkdwn conversion in streaming and preview
 paths

The native streaming path (chatStream) and preview final edit path
(chat.update) send raw Markdown text without converting to Slack
mrkdwn format. This causes **bold** to appear as literal asterisks
instead of rendered bold text.

Apply markdownToSlackMrkdwn() in streaming.ts (start/append/stop) and
in dispatch.ts (preview final edit via chat.update) to match the
non-streaming delivery path behavior.

Closes #31892
---
 src/slack/monitor/message-handler/dispatch.ts | 3 ++-
 src/slack/streaming.ts                        | 7 ++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/slack/monitor/message-handler/dispatch.ts b/src/slack/monitor/message-handler/dispatch.ts
index 8e3db47d5e6..2022100ce19 100644
--- a/src/slack/monitor/message-handler/dispatch.ts
+++ b/src/slack/monitor/message-handler/dispatch.ts
@@ -12,6 +12,7 @@ import { danger, logVerbose, shouldLogVerbose } from "../../../globals.js";
 import { resolveAgentOutboundIdentity } from "../../../infra/outbound/identity.js";
 import { removeSlackReaction } from "../../actions.js";
 import { createSlackDraftStream } from "../../draft-stream.js";
+import { markdownToSlackMrkdwn } from "../../format.js";
 import { recordSlackThreadParticipation } from "../../sent-thread-cache.js";
 import {
   applyAppendOnlyStreamUpdate,
@@ -290,7 +291,7 @@ export async function dispatchPreparedSlackMessage(prepared: PreparedSlackMessag
             token: ctx.botToken,
             channel: draftChannelId,
             ts: draftMessageId,
-            text: finalText.trim(),
+            text: markdownToSlackMrkdwn(finalText.trim()),
           });
           return;
         } catch (err) {
diff --git a/src/slack/streaming.ts b/src/slack/streaming.ts
index 936fba79feb..d2ed0e02612 100644
--- a/src/slack/streaming.ts
+++ b/src/slack/streaming.ts
@@ -14,6 +14,7 @@
 import type { WebClient } from "@slack/web-api";
 import type { ChatStreamer } from "@slack/web-api/dist/chat-stream.js";
 import { logVerbose } from "../globals.js";
+import { markdownToSlackMrkdwn } from "./format.js";
 
 // ---------------------------------------------------------------------------
 // Types
@@ -99,7 +100,7 @@ export async function startSlackStream(
   // If initial text is provided, send it as the first append which will
   // trigger the ChatStreamer to call chat.startStream under the hood.
   if (text) {
-    await streamer.append({ markdown_text: text });
+    await streamer.append({ markdown_text: markdownToSlackMrkdwn(text) });
     logVerbose(`slack-stream: appended initial text (${text.length} chars)`);
   }
 
@@ -121,7 +122,7 @@ export async function appendSlackStream(params: AppendSlackStreamParams): Promis
     return;
   }
 
-  await session.streamer.append({ markdown_text: text });
+  await session.streamer.append({ markdown_text: markdownToSlackMrkdwn(text) });
   logVerbose(`slack-stream: appended ${text.length} chars`);
 }
 
@@ -147,7 +148,7 @@ export async function stopSlackStream(params: StopSlackStreamParams): Promise<vo
     }`,
   );
 
-  await session.streamer.stop(text ? { markdown_text: text } : undefined);
+  await session.streamer.stop(text ? { markdown_text: markdownToSlackMrkdwn(text) } : undefined);
 
   logVerbose("slack-stream: stream stopped");
 }