include agent label in turn failure notification body

hive-ag3nt/src/bin/hive-ag3nt.rs

@@ -2,6 +2,8 @@ use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
+use hive_ag3nt::web_ui::TurnLock;
+
 use anyhow::Result;
 use clap::{Parser, Subcommand};
 use hive_ag3nt::events::{Bus, LiveEvent, TurnState};
@@ -71,14 +73,16 @@ async fn main() -> Result<()> {
             let login_state = Arc::new(Mutex::new(initial));
             let bus = Bus::new();
             let files = turn::TurnFiles::prepare(&cli.socket, &label, mcp::Flavor::Agent).await?;
+            let turn_lock: TurnLock = Arc::new(tokio::sync::Mutex::new(()));
             plugins::install_configured(&cli.socket, Some("manager")).await;
             tokio::spawn(web_ui::serve(
-                label,
+                label.clone(),
                 port,
                 login_state.clone(),
                 bus.clone(),
                 cli.socket.clone(),
                 files.clone(),
+                turn_lock.clone(),
             ));
             match initial {
                 LoginState::Online => {
@@ -88,6 +92,8 @@ async fn main() -> Result<()> {
                         login_state,
                         bus,
                         &files,
+                        turn_lock,
+                        &label,
                     )
                     .await
                 }
@@ -102,6 +108,8 @@ async fn main() -> Result<()> {
                         login_state,
                         bus,
                         &files,
+                        turn_lock,
+                        &label,
                     )
                     .await
                 }
@@ -136,6 +144,8 @@ async fn serve(
     state: Arc<Mutex<LoginState>>,
     bus: Bus,
     files: &turn::TurnFiles,
+    turn_lock: TurnLock,
+    label: &str,
 ) -> Result<()> {
     tracing::info!(socket = %socket.display(), "hive-ag3nt serve");
     let _ = state; // reserved for future state transitions (turn-loop -> needs-login)
@@ -163,7 +173,10 @@ async fn serve(
                 });
                 bus.set_state(TurnState::Thinking);
                 let prompt = format_wake_prompt(&from, &body, unread);
-                let outcome = turn::drive_turn(&prompt, files, &bus).await;
+                let outcome = {
+                    let _guard = turn_lock.lock().await;
+                    turn::drive_turn(&prompt, files, &bus).await
+                };
                 turn::emit_turn_end(&bus, &outcome);
                 bus.set_state(TurnState::Idle);
                 // Failures are unhandled by definition — PromptTooLong is
@@ -172,7 +185,7 @@ async fn serve(
                 // manager so it can investigate / restart / page the
                 // operator; best-effort, swallow the send error.
                 if let turn::TurnOutcome::Failed(e) = &outcome {
-                    notify_manager_of_failure(socket, e).await;
+                    notify_manager_of_failure(socket, label, e).await;
                 }
 
                 // After turn completes, check if there are pending messages waiting.
@@ -225,13 +238,15 @@ fn format_wake_prompt(from: &str, body: &str, unread: u64) -> String {
 /// Best-effort: tell the manager that this agent's last turn crashed
 /// (claude exited non-zero, compaction didn't help, etc.). Routed
 /// through the normal send path so the manager's inbox surfaces it
-/// like any other message; the agent's label is what the broker
+/// as a system-style event; `label` is included explicitly in the
-/// stamps as `from`, so the message body doesn't need to repeat it.
+/// body so the manager can identify the failing agent without having
-/// Swallows transport errors — we just logged the failure, the worst
+/// to look at the `from` field (which is broker-stamped and may
-/// case is the manager learns about the crash from the dashboard
+/// differ from what the operator sees in the dashboard). Swallows
-/// instead of inbox.
+/// transport errors — we just logged the failure, the worst case is
-async fn notify_manager_of_failure(socket: &Path, err: &anyhow::Error) {
+/// the manager learns about the crash from the dashboard instead of
-    let body = format!("claude turn failed:\n{err:#}");
+/// inbox.
+async fn notify_manager_of_failure(socket: &Path, label: &str, err: &anyhow::Error) {
+    let body = format!("[system] agent `{label}` claude turn failed:\n{err:#}");
     let res = client::request::<_, AgentResponse>(
         socket,
         &AgentRequest::Send {

hive-ag3nt/src/bin/hive-m1nd.rs

@@ -6,6 +6,8 @@ use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
+use hive_ag3nt::web_ui::TurnLock;
+
 use anyhow::Result;
 use clap::{Parser, Subcommand};
 use hive_ag3nt::events::{Bus, LiveEvent, TurnState};
@@ -61,6 +63,7 @@ async fn main() -> Result<()> {
             let login_state = Arc::new(Mutex::new(initial));
             let bus = Bus::new();
             let files = turn::TurnFiles::prepare(&cli.socket, &label, mcp::Flavor::Manager).await?;
+            let turn_lock: TurnLock = Arc::new(tokio::sync::Mutex::new(()));
             plugins::install_configured(&cli.socket, None).await;
             tokio::spawn(web_ui::serve(
                 label,
@@ -69,14 +72,15 @@ async fn main() -> Result<()> {
                 bus.clone(),
                 cli.socket.clone(),
                 files.clone(),
+                turn_lock.clone(),
             ));
             match initial {
                 LoginState::Online => {
-                    serve(&cli.socket, Duration::from_millis(poll_ms), bus, &files).await
+                    serve(&cli.socket, Duration::from_millis(poll_ms), bus, &files, turn_lock).await
                 }
                 LoginState::NeedsLogin => {
                     turn::wait_for_login(&claude_dir, login_state, poll_ms).await;
-                    serve(&cli.socket, Duration::from_millis(poll_ms), bus, &files).await
+                    serve(&cli.socket, Duration::from_millis(poll_ms), bus, &files, turn_lock).await
                 }
             }
         }
@@ -89,6 +93,7 @@ async fn serve(
     interval: Duration,
     bus: Bus,
     files: &turn::TurnFiles,
+    turn_lock: TurnLock,
 ) -> Result<()> {
     tracing::info!(socket = %socket.display(), "hive-m1nd serve");
     loop {
@@ -131,16 +136,30 @@ async fn serve(
                 });
                 let prompt = format_wake_prompt(&from, &body, unread);
                 bus.set_state(TurnState::Thinking);
-                let outcome = turn::drive_turn(&prompt, files, &bus).await;
+                let outcome = {
+                    let _guard = turn_lock.lock().await;
+                    turn::drive_turn(&prompt, files, &bus).await
+                };
                 turn::emit_turn_end(&bus, &outcome);
                 bus.set_state(TurnState::Idle);
+                // Check for messages that arrived during the turn and loop
+                // immediately if any are waiting — mirrors hive-ag3nt behaviour.
+                let pending = inbox_unread(socket).await;
+                if pending > 0 {
+                    tracing::info!(%pending, "pending messages after turn; fetching next");
+                    continue;
+                }
+            }
+            Ok(ManagerResponse::Empty) => {
+                // Idle: sleep briefly before next long-poll attempt.
+                tokio::time::sleep(interval).await;
             }
-            Ok(ManagerResponse::Empty) => {}
             Ok(
                 ManagerResponse::Ok
                 | ManagerResponse::Status { .. }
                 | ManagerResponse::QuestionQueued { .. }
-                | ManagerResponse::Recent { .. },
+                | ManagerResponse::Recent { .. }
+                | ManagerResponse::Logs { .. },
             ) => {
                 tracing::warn!("recv produced unexpected response kind");
             }
@@ -151,7 +170,6 @@ async fn serve(
                 tracing::warn!(error = ?e, "recv failed; retrying");
             }
         }
-        tokio::time::sleep(interval).await;
     }
 }
 

hive-ag3nt/src/mcp.rs

@@ -39,6 +39,7 @@ pub enum SocketReply {
     Status(u64),
     QuestionQueued(i64),
     Recent(Vec<hive_sh4re::InboxRow>),
+    Logs(String),
 }
 
 impl From<hive_sh4re::AgentResponse> for SocketReply {
@@ -65,6 +66,7 @@ impl From<hive_sh4re::ManagerResponse> for SocketReply {
             hive_sh4re::ManagerResponse::Status { unread } => Self::Status(unread),
             hive_sh4re::ManagerResponse::QuestionQueued { id } => Self::QuestionQueued(id),
             hive_sh4re::ManagerResponse::Recent { rows } => Self::Recent(rows),
+            hive_sh4re::ManagerResponse::Logs { content } => Self::Logs(content),
         }
     }
 }
@@ -351,6 +353,15 @@ pub struct RequestApplyCommitArgs {
     pub description: Option<String>,
 }
 
+#[derive(Debug, serde::Deserialize, schemars::JsonSchema)]
+pub struct GetLogsArgs {
+    /// Logical name of the sub-agent container to fetch logs for.
+    pub agent: String,
+    /// How many journal lines to return (default: 50, max: 500).
+    #[serde(default)]
+    pub lines: Option<u32>,
+}
+
 #[derive(Debug, Clone)]
 pub struct ManagerServer {
     socket: PathBuf,
@@ -580,6 +591,40 @@ impl ManagerServer {
         })
         .await
     }
+
+    #[tool(
+        description = "Fetch recent journal log lines for a sub-agent container. Useful \
+        for diagnosing MCP server registration failures, startup crashes, plugin install \
+        errors, or any harness issue you can't see from inside the container. `lines` \
+        defaults to 50 (max capped at 500 on the host side)."
+    )]
+    async fn get_logs(&self, Parameters(args): Parameters<GetLogsArgs>) -> String {
+        let log = format!("{args:?}");
+        let agent = args.agent.clone();
+        run_tool_envelope("get_logs", log, async move {
+            let lines = args.lines.map(|n| n.min(500));
+            let (resp, retries) = self
+                .dispatch(hive_sh4re::ManagerRequest::GetLogs {
+                    agent: agent.clone(),
+                    lines,
+                })
+                .await;
+            let s = match resp {
+                Ok(SocketReply::Logs(content)) => {
+                    if content.is_empty() {
+                        format!("(no journal output for {agent})")
+                    } else {
+                        content
+                    }
+                }
+                Ok(SocketReply::Err(m)) => format!("get_logs failed: {m}"),
+                Ok(other) => format!("get_logs unexpected response: {other:?}"),
+                Err(e) => format!("get_logs transport error: {e:#}"),
+            };
+            annotate_retries(s, retries)
+        })
+        .await
+    }
 }
 
 #[tool_handler(
@@ -635,6 +680,7 @@ pub fn allowed_mcp_tools(flavor: Flavor) -> Vec<String> {
             "update",
             "request_apply_commit",
             "ask_operator",
+            "get_logs",
         ],
     };
     let mut out: Vec<String> = names

hive-ag3nt/src/web_ui.rs

@@ -36,6 +36,12 @@ use crate::turn::TurnFiles;
 /// render.
 pub type LoginStateCell = Arc<Mutex<LoginState>>;
 
+/// Shared turn lock. The serve loop acquires this (as an async mutex) for the
+/// duration of every `drive_turn` call. The `/api/compact` handler tries
+/// `try_lock()` and rejects immediately if a turn is in flight, preventing
+/// concurrent access to the claude session.
+pub type TurnLock = Arc<tokio::sync::Mutex<()>>;
+
 #[derive(Clone)]
 struct AppState {
     label: String,
@@ -48,6 +54,8 @@ struct AppState {
     /// settings claude saw on the last regular turn — keeps the
     /// session shape identical across compact + normal turns.
     files: TurnFiles,
+    /// Prevents `/api/compact` from racing with an in-flight normal turn.
+    turn_lock: TurnLock,
 }
 
 impl AppState {
@@ -70,6 +78,7 @@ pub async fn serve(
     bus: Bus,
     socket: PathBuf,
     files: TurnFiles,
+    turn_lock: TurnLock,
 ) -> Result<()> {
     let state = AppState {
         label,
@@ -78,6 +87,7 @@ pub async fn serve(
         bus,
         socket,
         files,
+        turn_lock,
     };
     let app = Router::new()
         .route("/", get(serve_index))
@@ -406,9 +416,21 @@ async fn post_set_model(State(state): State<AppState>, Form(form): Form<ModelFor
 }
 
 async fn post_compact(State(state): State<AppState>) -> Response {
+    // Clone the Arc before locking so the guard's lifetime is tied to the
+    // clone (which we can move into the spawn) rather than to `state`.
+    let lock = state.turn_lock.clone();
+    // Reject immediately if a normal turn is in flight — concurrent access
+    // to the claude session is unsafe and produces garbled output.
+    let guard = match lock.try_lock_owned() {
+        Ok(g) => g,
+        Err(_) => {
+            return error_response("turn in flight — wait for it to finish before compacting");
+        }
+    };
     let bus = state.bus.clone();
     let files = state.files.clone();
     tokio::spawn(async move {
+        let _guard = guard; // keep lock alive for the duration of compaction
         bus.emit(crate::events::LiveEvent::Note(
             "operator: /compact — running on persistent session".into(),
         ));

hive-c0re/src/manager_server.rs

@@ -273,6 +273,35 @@ async fn dispatch(req: &ManagerRequest, coord: &Arc<Coordinator>) -> ManagerResp
                 },
             }
         }
+        ManagerRequest::GetLogs { agent, lines } => {
+            let n = lines.unwrap_or(50);
+            tracing::info!(%agent, %n, "manager: get_logs");
+            match tokio::process::Command::new("journalctl")
+                .args([
+                    "-M",
+                    agent,
+                    "-n",
+                    &n.to_string(),
+                    "--no-pager",
+                    "--output=short",
+                ])
+                .output()
+                .await
+            {
+                Ok(out) => {
+                    let content = if out.status.success() || !out.stdout.is_empty() {
+                        String::from_utf8_lossy(&out.stdout).into_owned()
+                    } else {
+                        let stderr = String::from_utf8_lossy(&out.stderr);
+                        format!("journalctl exited {}: {stderr}", out.status)
+                    };
+                    ManagerResponse::Logs { content }
+                }
+                Err(e) => ManagerResponse::Err {
+                    message: format!("journalctl spawn failed: {e:#}"),
+                },
+            }
+        }
         ManagerRequest::RequestApplyCommit {
             agent,
             commit_ref,

hive-sh4re/src/lib.rs

@@ -475,6 +475,17 @@ pub enum ManagerRequest {
         #[serde(default)]
         ttl_seconds: Option<u64>,
     },
+    /// Fetch recent journal lines for a sub-agent container. hive-c0re
+    /// runs `journalctl -M <agent> -n <lines> --no-pager` and returns
+    /// the output as a string. Useful for diagnosing MCP registration
+    /// failures, startup crashes, and harness errors.
+    ///
+    /// `lines` defaults to 50 when omitted.
+    GetLogs {
+        agent: String,
+        #[serde(default)]
+        lines: Option<u32>,
+    },
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -502,4 +513,8 @@ pub enum ManagerResponse {
     Recent {
         rows: Vec<InboxRow>,
     },
+    /// `GetLogs` result: journal lines for the requested container.
+    Logs {
+        content: String,
+    },
 }