feat(telegram): inject bot self-identity into agent system prompt

After stripBotMention removes the bot's own @mention from content, the LLM
still lacks knowledge of its own platform handle. In multi-bot groups (e.g.
"@botA @botB do X") the other bot's mention remains in the content and the
agent incorrectly treats it as the intended target, replying NO_REPLY.

Capture the bot's first_name from GetMe during channel Start and expose it
alongside the username via a new MetaChannelSelfIdentity metadata key. The
consumer appends the formatted hint ("You are @{username} ({display_name})
on this Telegram channel.") to the agent's extraSystemPrompt so the LLM can
reliably identify itself across single- and multi-bot scenarios.

Falls back to "You are @{username} on this Telegram channel." when the
display name is not available, and no-ops when the username has not been
resolved yet (startup race).

cmd/gateway_consumer_normal.go

@@ -255,6 +255,16 @@ func processNormalMessage(
 		extraPrompt += tsp
 	}
 
+	// Append channel-provided self-identity hint (e.g. "You are @bot (Name) on Telegram").
+	// Prevents the LLM from treating its own platform handle as another bot when users
+	// @mention it directly or reference it alongside another bot in multi-bot groups.
+	if identity := msg.Metadata[tools.MetaChannelSelfIdentity]; identity != "" {
+		if extraPrompt != "" {
+			extraPrompt += "\n\n"
+		}
+		extraPrompt += identity
+	}
+
 	// Per-topic skill filter override (from group/topic config hierarchy).
 	var skillFilter []string
 	if ts := msg.Metadata[tools.MetaTopicSkills]; ts != "" {

internal/channels/telegram/channel.go

@@ -39,6 +39,7 @@ type Channel struct {
 	reactions         sync.Map                    // localKey string → *StatusReactionController
 	threadIDs         sync.Map                    // localKey string → messageThreadID int (for forum topic routing)
 	mentionMode       string             // "strict" (default) or "yield"
+	botDisplayName    string             // bot's first_name from GetMe (e.g. "ViệtBot"); captured once at Start
 	pollCancel        context.CancelFunc // cancels the long polling context
 	pollDone          chan struct{}      // closed when polling goroutine exits
 	handlerWg         sync.WaitGroup     // tracks in-flight handler goroutines for graceful shutdown
@@ -189,6 +190,7 @@ func (c *Channel) Start(ctx context.Context) error {
 	username := ""
 	if me != nil {
 		username = me.Username
+		c.botDisplayName = me.FirstName
 	}
 
 	// Create a cancellable context for the polling goroutine.

internal/channels/telegram/handlers.go

@@ -595,6 +595,12 @@ func (c *Channel) handleMessage(ctx context.Context, update telego.Update) {
 		metadata[tools.MetaDMThreadID] = fmt.Sprintf("%d", dmThreadID)
 		metadata[tools.MetaMessageThreadID] = fmt.Sprintf("%d", dmThreadID)
 	}
+	// Self-identity hint so the LLM knows its own Telegram handle and does not
+	// confuse other bots' @mentions (preserved after stripBotMention) for its own.
+	if identity := buildSelfIdentityPrompt(c.bot.Username(), c.botDisplayName); identity != "" {
+		metadata[tools.MetaChannelSelfIdentity] = identity
+	}
+
 	if topicCfg.systemPrompt != "" {
 		metadata[tools.MetaTopicSystemPrompt] = topicCfg.systemPrompt
 	}

internal/channels/telegram/handlers_utils.go

@@ -1,12 +1,28 @@
 package telegram
 
 import (
+	"fmt"
 	"regexp"
 	"strings"
 
 	"github.com/mymmrac/telego"
 )
 
+// buildSelfIdentityPrompt returns a short system-prompt snippet telling the LLM
+// which Telegram handle represents itself, so it does not confuse its own
+// @mention for a different bot — especially useful in multi-bot groups where
+// other bots' mentions remain in the content after stripBotMention.
+// Returns empty string when the bot username has not been resolved yet.
+func buildSelfIdentityPrompt(botUsername, displayName string) string {
+	if botUsername == "" {
+		return ""
+	}
+	if displayName != "" {
+		return fmt.Sprintf("You are @%s (%s) on this Telegram channel.", botUsername, displayName)
+	}
+	return fmt.Sprintf("You are @%s on this Telegram channel.", botUsername)
+}
+
 // stripBotMention removes @botUsername tokens from text (case-insensitive).
 // Applied after the mention gate passes so the LLM does not see its own Telegram handle
 // and mistake itself for another bot (e.g. persona "Tiểu Hổ" receiving "@viet_super_bot vẽ...").

internal/channels/telegram/handlers_utils_test.go

@@ -272,6 +272,30 @@ func TestStripBotMention_OnlyMentionBecomesEmpty(t *testing.T) {
 	}
 }
 
+// --- buildSelfIdentityPrompt ---
+
+func TestBuildSelfIdentityPrompt_WithDisplayName(t *testing.T) {
+	got := buildSelfIdentityPrompt("viet_super_bot", "ViệtBot")
+	want := "You are @viet_super_bot (ViệtBot) on this Telegram channel."
+	if got != want {
+		t.Errorf("buildSelfIdentityPrompt = %q, want %q", got, want)
+	}
+}
+
+func TestBuildSelfIdentityPrompt_NoDisplayName(t *testing.T) {
+	got := buildSelfIdentityPrompt("viet_super_bot", "")
+	want := "You are @viet_super_bot on this Telegram channel."
+	if got != want {
+		t.Errorf("buildSelfIdentityPrompt = %q, want %q", got, want)
+	}
+}
+
+func TestBuildSelfIdentityPrompt_EmptyUsername(t *testing.T) {
+	if got := buildSelfIdentityPrompt("", "Name"); got != "" {
+		t.Errorf("buildSelfIdentityPrompt with empty username should return empty; got %q", got)
+	}
+}
+
 // --- isServiceMessage ---
 
 func TestIsServiceMessage_WithText(t *testing.T) {

internal/tools/team_metadata_keys.go

@@ -44,6 +44,11 @@ const (
 	MetaUserName         = "user_name"
 	MetaTopicSystemPrompt = "topic_system_prompt"
 	MetaTopicSkills      = "topic_skills"
+	// MetaChannelSelfIdentity carries a channel-provided self-identity hint
+	// (e.g. "You are @viet_super_bot (ViệtBot) on this Telegram channel.")
+	// appended to the agent's system prompt so the LLM does not confuse its own
+	// platform handle for a different bot when users @mention it.
+	MetaChannelSelfIdentity = "channel_self_identity"
 )
 
 // Task metadata keys stored in store.TeamTaskData.Metadata.