refactor: centralize group sender identity

src/telegram/bot-message-context.ts

@@ -15,7 +15,6 @@ import { recordChannelActivity } from "../infra/channel-activity.js";
 import { resolveAgentRoute } from "../routing/resolve-route.js";
 import { resolveMentionGating } from "../channels/mention-gating.js";
 import {
-  buildGroupFromLabel,
   buildGroupLabel,
   buildSenderLabel,
   buildSenderName,
@@ -324,15 +323,15 @@ export const buildTelegramMessageContext = async ({
         replyTarget.id ? ` id:${replyTarget.id}` : ""
       }]\n${replyTarget.body}\n[/Replying]`
     : "";
-  const groupLabel = isGroup ? buildGroupLabel(msg, chatId, resolvedThreadId) : undefined;
-  const body = formatAgentEnvelope({
-    channel: "Telegram",
-    from: isGroup
-      ? buildGroupFromLabel(msg, chatId, senderId, resolvedThreadId)
-      : buildSenderLabel(msg, senderId || chatId),
-    timestamp: msg.date ? msg.date * 1000 : undefined,
-    body: `${bodyText}${replySuffix}`,
-  });
+	  const groupLabel = isGroup ? buildGroupLabel(msg, chatId, resolvedThreadId) : undefined;
+	  const body = formatAgentEnvelope({
+	    channel: "Telegram",
+	    from: isGroup
+	      ? (groupLabel ?? `group:${chatId}`)
+	      : buildSenderLabel(msg, senderId || chatId),
+	    timestamp: msg.date ? msg.date * 1000 : undefined,
+	    body: `${bodyText}${replySuffix}`,
+	  });
   let combinedBody = body;
   if (isGroup && historyKey && historyLimit > 0) {
     combinedBody = buildPendingHistoryContextFromMap({

src/telegram/bot.create-telegram-bot.accepts-group-messages-mentionpatterns-match-without-botusername.test.ts

@@ -171,15 +171,17 @@ describe("createTelegramBot", () => {
       getFile: async () => ({ download: async () => new Uint8Array() }),
     });
 
-    expect(replySpy).toHaveBeenCalledTimes(1);
-    const payload = replySpy.mock.calls[0][0];
-    expect(payload.WasMentioned).toBe(true);
-    expect(payload.Body).toMatch(/^\[Telegram Test Group id:7 from Ada id:9 2025-01-09T00:00Z\]/);
-  });
-  it("includes sender identity in group envelope headers", async () => {
-    onSpy.mockReset();
-    const replySpy = replyModule.__replySpy as unknown as ReturnType<typeof vi.fn>;
-    replySpy.mockReset();
+	    expect(replySpy).toHaveBeenCalledTimes(1);
+	    const payload = replySpy.mock.calls[0][0];
+	    expect(payload.WasMentioned).toBe(true);
+	    expect(payload.SenderName).toBe("Ada");
+	    expect(payload.SenderId).toBe("9");
+	    expect(payload.Body).toMatch(/^\[Telegram Test Group id:7 2025-01-09T00:00Z\]/);
+	  });
+	  it("keeps group envelope headers stable (sender identity is separate)", async () => {
+	    onSpy.mockReset();
+	    const replySpy = replyModule.__replySpy as unknown as ReturnType<typeof vi.fn>;
+	    replySpy.mockReset();
 
     loadConfig.mockReturnValue({
       channels: {
@@ -210,12 +212,13 @@ describe("createTelegramBot", () => {
       getFile: async () => ({ download: async () => new Uint8Array() }),
     });
 
-    expect(replySpy).toHaveBeenCalledTimes(1);
-    const payload = replySpy.mock.calls[0][0];
-    expect(payload.Body).toMatch(
-      /^\[Telegram Ops id:42 from Ada Lovelace \(@ada\) id:99 2025-01-09T00:00Z\]/,
-    );
-  });
+	    expect(replySpy).toHaveBeenCalledTimes(1);
+	    const payload = replySpy.mock.calls[0][0];
+      expect(payload.SenderName).toBe("Ada Lovelace");
+      expect(payload.SenderId).toBe("99");
+      expect(payload.SenderUsername).toBe("ada");
+	    expect(payload.Body).toMatch(/^\[Telegram Ops id:42 2025-01-09T00:00Z\]/);
+	  });
   it("reacts to mention-gated group messages when ackReaction is enabled", async () => {
     onSpy.mockReset();
     setMessageReactionSpy.mockReset();

src/telegram/bot.test.ts

@@ -584,7 +584,9 @@ describe("createTelegramBot", () => {
     expect(replySpy).toHaveBeenCalledTimes(1);
     const payload = replySpy.mock.calls[0][0];
     expect(payload.WasMentioned).toBe(true);
-    expect(payload.Body).toMatch(/^\[Telegram Test Group id:7 from Ada id:9 2025-01-09T00:00Z\]/);
+    expect(payload.Body).toMatch(/^\[Telegram Test Group id:7 2025-01-09T00:00Z\]/);
+    expect(payload.SenderName).toBe("Ada");
+    expect(payload.SenderId).toBe("9");
   });
 
   it("includes sender identity in group envelope headers", async () => {
@@ -623,9 +625,10 @@ describe("createTelegramBot", () => {
 
     expect(replySpy).toHaveBeenCalledTimes(1);
     const payload = replySpy.mock.calls[0][0];
-    expect(payload.Body).toMatch(
-      /^\[Telegram Ops id:42 from Ada Lovelace \(@ada\) id:99 2025-01-09T00:00Z\]/,
-    );
+    expect(payload.Body).toMatch(/^\[Telegram Ops id:42 2025-01-09T00:00Z\]/);
+    expect(payload.SenderName).toBe("Ada Lovelace");
+    expect(payload.SenderId).toBe("99");
+    expect(payload.SenderUsername).toBe("ada");
   });
 
   it("reacts to mention-gated group messages when ackReaction is enabled", async () => {

src/telegram/bot/helpers.ts

@@ -98,17 +98,6 @@ export function buildGroupLabel(
   return `group:${chatId}${topicSuffix}`;
 }
 
-export function buildGroupFromLabel(
-  msg: TelegramMessage,
-  chatId: number | string,
-  senderId?: number | string,
-  messageThreadId?: number,
-) {
-  const groupLabel = buildGroupLabel(msg, chatId, messageThreadId);
-  const senderLabel = buildSenderLabel(msg, senderId);
-  return `${groupLabel} from ${senderLabel}`;
-}
-
 export function hasBotMention(msg: TelegramMessage, botUsername: string) {
   const text = (msg.text ?? msg.caption ?? "").toLowerCase();
   if (text.includes(`@${botUsername}`)) return true;