fix reply_target chain to use String instead of u64, fix UTF-8 boundary panic in attachment truncation, improve Telegram/webhook channel_name metadata

Author: jamiepine

src/agent/channel.rs

@@ -70,7 +70,7 @@ pub struct ChannelState {
     pub conversation_logger: ConversationLogger,
     pub process_run_logger: ProcessRunLogger,
     /// Discord message ID to reply to for work spawned in the current turn.
-    pub reply_target_message_id: Arc<RwLock<Option<u64>>>,
+    pub reply_target_message_id: Arc<RwLock<Option<String>>>,
     pub channel_store: ChannelStore,
     pub screenshot_dir: std::path::PathBuf,
     pub logs_dir: std::path::PathBuf,
@@ -155,7 +155,7 @@ pub struct Channel {
     /// Branch IDs for silent memory persistence branches (results not injected into history).
     memory_persistence_branches: HashSet<BranchId>,
     /// Optional Discord reply target captured when each branch was started.
-    branch_reply_targets: HashMap<BranchId, u64>,
+    branch_reply_targets: HashMap<BranchId, String>,
     /// Buffer for coalescing rapid-fire messages.
     coalesce_buffer: Vec<InboundMessage>,
     /// Deadline for flushing the coalesce buffer.
@@ -1437,7 +1437,8 @@ impl Channel {
             } => {
                 run_logger.log_branch_started(channel_id, *branch_id, description);
                 if let Some(message_id) = reply_to_message_id {
-                    self.branch_reply_targets.insert(*branch_id, *message_id);
+                    self.branch_reply_targets
+                        .insert(*branch_id, message_id.clone());
                 }
             }
             ProcessEvent::BranchResult {

src/agent/channel_attachments.rs

@@ -417,9 +417,10 @@ async fn download_text_attachment(
 
     // Truncate very large files to avoid blowing up context
     let truncated = if content.len() > 50_000 {
+        let end = content.floor_char_boundary(50_000);
         format!(
             "{}...\n[truncated — {} bytes total]",
-            &content[..50_000],
+            &content[..end],
             content.len()
         )
     } else {

src/agent/channel_dispatch.rs

@@ -199,7 +199,7 @@ async fn spawn_branch(
             branch_id,
             channel_id: state.channel_id.clone(),
             description: status_label.to_string(),
-            reply_to_message_id: *state.reply_target_message_id.read().await,
+            reply_to_message_id: state.reply_target_message_id.read().await.clone(),
         })
         .ok();
 

src/agent/channel_history.rs

@@ -334,11 +334,15 @@ pub(crate) fn format_batched_user_message(
     format!("[{display_name}] ({absolute_timestamp}; {relative_text}): {text_content}")
 }
 
-pub(crate) fn extract_message_id(message: &InboundMessage) -> Option<u64> {
+pub(crate) fn extract_message_id(message: &InboundMessage) -> Option<String> {
     message
         .metadata
         .get(crate::metadata_keys::MESSAGE_ID)
-        .and_then(|value| value.as_u64())
+        .and_then(|value| match value {
+            serde_json::Value::String(s) => Some(s.clone()),
+            serde_json::Value::Number(n) => Some(n.to_string()),
+            _ => None,
+        })
 }
 
 /// Check if a ProcessEvent is targeted at a specific channel.

src/lib.rs

@@ -104,7 +104,7 @@ pub enum ProcessEvent {
         branch_id: BranchId,
         channel_id: ChannelId,
         description: String,
-        reply_to_message_id: Option<u64>,
+        reply_to_message_id: Option<String>,
     },
     BranchResult {
         agent_id: AgentId,

src/messaging/discord.rs

@@ -89,7 +89,11 @@ impl DiscordAdapter {
         message
             .metadata
             .get(crate::metadata_keys::REPLY_TO_MESSAGE_ID)
-            .and_then(|value| value.as_u64())
+            .and_then(|value| match value {
+                serde_json::Value::String(s) => s.parse::<u64>().ok(),
+                serde_json::Value::Number(n) => n.as_u64(),
+                _ => None,
+            })
             .map(MessageId::new)
     }
 }

src/messaging/telegram.rs

@@ -818,7 +818,16 @@ fn build_metadata(
         metadata.insert("telegram_chat_title".into(), (*title).into());
         metadata.insert(crate::metadata_keys::SERVER_NAME.into(), (*title).into());
     }
-    metadata.insert(crate::metadata_keys::CHANNEL_NAME.into(), chat_type.into());
+    let channel_name = message
+        .chat
+        .title()
+        .map(|title| title.to_string())
+        .or_else(|| message.from.as_ref().map(build_display_name))
+        .unwrap_or_else(|| chat_type.to_string());
+    metadata.insert(
+        crate::metadata_keys::CHANNEL_NAME.into(),
+        channel_name.into(),
+    );
 
     let formatted_author = if let Some(from) = &message.from {
         metadata.insert(

src/messaging/webhook.rs

@@ -268,6 +268,10 @@ async fn handle_send(
         "sender_display_name".into(),
         serde_json::Value::String(request.sender_id.clone()),
     );
+    metadata.insert(
+        crate::metadata_keys::CHANNEL_NAME.into(),
+        serde_json::Value::String(request.conversation_id.clone()),
+    );
 
     let conversation_id = format!("webhook:{}", request.conversation_id);