diff --git a/server/src/agents/pty/events.rs b/server/src/agents/pty/events.rs
new file mode 100644
index 00000000..36d568a2
--- /dev/null
+++ b/server/src/agents/pty/events.rs
@@ -0,0 +1,80 @@
+//! Event emission helpers: routing PTY output lines to the broadcast channel and log.
+use std::sync::Mutex;
+
+use tokio::sync::broadcast;
+
+use crate::agent_log::AgentLogWriter;
+use crate::agents::AgentEvent;
+
+/// Dispatch a `stream_event` from Claude Code's `--include-partial-messages` output.
+///
+/// Extracts `thinking_delta` and `text_delta` from `content_block_delta` events
+/// and routes them as `AgentEvent::Thinking` and `AgentEvent::Output` respectively.
+/// This ensures thinking traces flow through the dedicated `ThinkingBlock` UI
+/// component rather than appearing as unbounded regular output.
+pub(super) fn handle_agent_stream_event(
+    event: &serde_json::Value,
+    story_id: &str,
+    agent_name: &str,
+    tx: &broadcast::Sender<AgentEvent>,
+    event_log: &Mutex<Vec<AgentEvent>>,
+    log_writer: Option<&Mutex<AgentLogWriter>>,
+) {
+    let event_type = event.get("type").and_then(|t| t.as_str()).unwrap_or("");
+
+    if event_type == "content_block_delta"
+        && let Some(delta) = event.get("delta")
+    {
+        let delta_type = delta.get("type").and_then(|t| t.as_str()).unwrap_or("");
+        match delta_type {
+            "thinking_delta" => {
+                if let Some(thinking) = delta.get("thinking").and_then(|t| t.as_str()) {
+                    emit_event(
+                        AgentEvent::Thinking {
+                            story_id: story_id.to_string(),
+                            agent_name: agent_name.to_string(),
+                            text: thinking.to_string(),
+                        },
+                        tx,
+                        event_log,
+                        log_writer,
+                    );
+                }
+            }
+            "text_delta" => {
+                if let Some(text) = delta.get("text").and_then(|t| t.as_str()) {
+                    emit_event(
+                        AgentEvent::Output {
+                            story_id: story_id.to_string(),
+                            agent_name: agent_name.to_string(),
+                            text: text.to_string(),
+                        },
+                        tx,
+                        event_log,
+                        log_writer,
+                    );
+                }
+            }
+            _ => {}
+        }
+    }
+}
+
+/// Helper to send an event to broadcast, event log, and optional persistent log file.
+pub(in crate::agents) fn emit_event(
+    event: AgentEvent,
+    tx: &broadcast::Sender<AgentEvent>,
+    event_log: &Mutex<Vec<AgentEvent>>,
+    log_writer: Option<&Mutex<AgentLogWriter>>,
+) {
+    if let Ok(mut log) = event_log.lock() {
+        log.push(event.clone());
+    }
+    if let Some(writer) = log_writer
+        && let Ok(mut w) = writer.lock()
+        && let Err(e) = w.write_event(&event)
+    {
+        eprintln!("[agent_log] Failed to write event to log file: {e}");
+    }
+    let _ = tx.send(event);
+}
diff --git a/server/src/agents/pty/mod.rs b/server/src/agents/pty/mod.rs
new file mode 100644
index 00000000..2f56477b
--- /dev/null
+++ b/server/src/agents/pty/mod.rs
@@ -0,0 +1,328 @@
+//! PTY runner — spawns agent processes in pseudo-terminals and streams their output.
+
+mod events;
+mod runner;
+mod types;
+
+pub(in crate::agents) use events::emit_event;
+pub(in crate::agents) use runner::run_agent_pty_streaming;
+
+#[cfg(test)]
+mod tests {
+    use super::events::handle_agent_stream_event;
+    use super::*;
+    use crate::agents::AgentEvent;
+    use crate::io::watcher::WatcherEvent;
+    use std::collections::HashMap;
+    use std::sync::{Arc, Mutex};
+    use tokio::sync::broadcast;
+
+    // ── AC1: pty detects rate_limit_event and emits RateLimitWarning ─────────
+
+    /// Verify that when a `rate_limit_event` JSON line appears in PTY output,
+    /// `run_agent_pty_streaming` sends a `WatcherEvent::RateLimitWarning` with
+    /// the correct story_id and agent_name.
+    ///
+    /// The command invoked is: `sh -p -- <script>` where `--` terminates
+    /// option parsing so the script path is treated as the operand.
+    #[tokio::test]
+    async fn rate_limit_event_json_sends_watcher_warning() {
+        use std::os::unix::fs::PermissionsExt;
+
+        let tmp = tempfile::tempdir().unwrap();
+        let script = tmp.path().join("emit_rate_limit.sh");
+        std::fs::write(
+            &script,
+            "#!/bin/sh\nprintf '%s\\n' '{\"type\":\"rate_limit_event\",\"rate_limit_info\":{\"status\":\"allowed_warning\"}}'\n",
+        )
+        .unwrap();
+        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
+
+        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
+        let (watcher_tx, mut watcher_rx) = broadcast::channel::<WatcherEvent>(16);
+        let event_log = Arc::new(Mutex::new(Vec::new()));
+        let child_killers = Arc::new(Mutex::new(HashMap::new()));
+
+        // sh -p "--" <script>: -p = privileged mode, "--" = end options,
+        // then the script path is the file operand.
+        let result = run_agent_pty_streaming(
+            "365_story_test",
+            "coder-1",
+            "sh",
+            &[script.to_string_lossy().to_string()],
+            "--",
+            "/tmp",
+            &tx,
+            &event_log,
+            None,
+            0,
+            child_killers,
+            watcher_tx,
+            None,
+        )
+        .await;
+
+        assert!(result.is_ok(), "PTY run should succeed: {:?}", result.err());
+
+        let evt = watcher_rx
+            .try_recv()
+            .expect("Expected a RateLimitWarning to be sent on watcher_tx");
+        match evt {
+            WatcherEvent::RateLimitWarning {
+                story_id,
+                agent_name,
+            } => {
+                assert_eq!(story_id, "365_story_test");
+                assert_eq!(agent_name, "coder-1");
+            }
+            other => panic!("Expected RateLimitWarning, got: {other:?}"),
+        }
+    }
+
+    /// AC1: hard block with `reset_at` emits `RateLimitHardBlock` with the
+    /// correct story_id, agent_name, and parsed reset_at timestamp.
+    #[tokio::test]
+    async fn rate_limit_hard_block_sends_watcher_hard_block_event() {
+        use std::os::unix::fs::PermissionsExt;
+
+        let tmp = tempfile::tempdir().unwrap();
+        let script = tmp.path().join("emit_hard_block.sh");
+        std::fs::write(
+            &script,
+            "#!/bin/sh\nprintf '%s\\n' '{\"type\":\"rate_limit_event\",\"rate_limit_info\":{\"status\":\"hard_block\",\"reset_at\":\"2099-01-01T12:00:00Z\"}}'\n",
+        )
+        .unwrap();
+        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
+
+        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
+        let (watcher_tx, mut watcher_rx) = broadcast::channel::<WatcherEvent>(16);
+        let event_log = Arc::new(Mutex::new(Vec::new()));
+        let child_killers = Arc::new(Mutex::new(HashMap::new()));
+
+        let result = run_agent_pty_streaming(
+            "423_story_rate_limit",
+            "coder-1",
+            "sh",
+            &[script.to_string_lossy().to_string()],
+            "--",
+            "/tmp",
+            &tx,
+            &event_log,
+            None,
+            0,
+            child_killers,
+            watcher_tx,
+            None,
+        )
+        .await;
+
+        assert!(result.is_ok(), "PTY run should succeed: {:?}", result.err());
+
+        let evt = watcher_rx
+            .try_recv()
+            .expect("Expected a RateLimitHardBlock to be sent on watcher_tx");
+        match evt {
+            WatcherEvent::RateLimitHardBlock {
+                story_id,
+                agent_name,
+                reset_at,
+            } => {
+                assert_eq!(story_id, "423_story_rate_limit");
+                assert_eq!(agent_name, "coder-1");
+                assert_eq!(
+                    reset_at.to_rfc3339(),
+                    "2099-01-01T12:00:00+00:00",
+                    "reset_at should match the parsed timestamp"
+                );
+            }
+            other => panic!("Expected RateLimitHardBlock, got: {other:?}"),
+        }
+    }
+
+    /// Bug 496: hard block WITHOUT `reset_at` must still emit `RateLimitHardBlock`
+    /// (not `RateLimitWarning`), using a default 5-minute backoff so the
+    /// auto-scheduler can set a retry timer.
+    #[tokio::test]
+    async fn rate_limit_hard_block_without_reset_at_sends_hard_block_event() {
+        use std::os::unix::fs::PermissionsExt;
+
+        let tmp = tempfile::tempdir().unwrap();
+        let script = tmp.path().join("emit_hard_block_no_reset.sh");
+        std::fs::write(
+            &script,
+            "#!/bin/sh\nprintf '%s\\n' '{\"type\":\"rate_limit_event\",\"rate_limit_info\":{\"status\":\"rejected\"}}'\n",
+        )
+        .unwrap();
+        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
+
+        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
+        let (watcher_tx, mut watcher_rx) = broadcast::channel::<WatcherEvent>(16);
+        let event_log = Arc::new(Mutex::new(Vec::new()));
+        let child_killers = Arc::new(Mutex::new(HashMap::new()));
+
+        let before = chrono::Utc::now();
+        let result = run_agent_pty_streaming(
+            "496_bug_hard_rate_limit",
+            "coder-1",
+            "sh",
+            &[script.to_string_lossy().to_string()],
+            "--",
+            "/tmp",
+            &tx,
+            &event_log,
+            None,
+            0,
+            child_killers,
+            watcher_tx,
+            None,
+        )
+        .await;
+        let after = chrono::Utc::now();
+
+        assert!(result.is_ok(), "PTY run should succeed: {:?}", result.err());
+
+        let evt = watcher_rx
+            .try_recv()
+            .expect("Expected a RateLimitHardBlock to be sent on watcher_tx");
+        match evt {
+            WatcherEvent::RateLimitHardBlock {
+                story_id,
+                agent_name,
+                reset_at,
+            } => {
+                assert_eq!(story_id, "496_bug_hard_rate_limit");
+                assert_eq!(agent_name, "coder-1");
+                // reset_at should be ~5 minutes from when the event fired
+                let min_expected = before + chrono::Duration::minutes(4);
+                let max_expected = after + chrono::Duration::minutes(6);
+                assert!(
+                    reset_at >= min_expected && reset_at <= max_expected,
+                    "reset_at {reset_at} should be ~5 minutes from now"
+                );
+            }
+            other => panic!("Expected RateLimitHardBlock (with default backoff), got: {other:?}"),
+        }
+    }
+
+    #[test]
+    fn test_emit_event_writes_to_log_writer() {
+        let tmp = tempfile::tempdir().unwrap();
+        let root = tmp.path();
+
+        let log_writer =
+            crate::agent_log::AgentLogWriter::new(root, "42_story_foo", "coder-1", "sess-emit")
+                .unwrap();
+        let log_mutex = Mutex::new(log_writer);
+
+        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
+        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
+
+        let event = AgentEvent::Status {
+            story_id: "42_story_foo".to_string(),
+            agent_name: "coder-1".to_string(),
+            status: "running".to_string(),
+        };
+
+        emit_event(event, &tx, &event_log, Some(&log_mutex));
+
+        // Verify event was added to in-memory log
+        let mem_events = event_log.lock().unwrap();
+        assert_eq!(mem_events.len(), 1);
+        drop(mem_events);
+
+        // Verify event was written to the log file
+        let log_path =
+            crate::agent_log::log_file_path(root, "42_story_foo", "coder-1", "sess-emit");
+        let entries = crate::agent_log::read_log(&log_path).unwrap();
+        assert_eq!(entries.len(), 1);
+        assert_eq!(entries[0].event["type"], "status");
+        assert_eq!(entries[0].event["status"], "running");
+    }
+
+    // ── bug 167: handle_agent_stream_event routes thinking/text correctly ───
+
+    #[test]
+    fn stream_event_thinking_delta_emits_thinking_event() {
+        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
+        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
+
+        let event = serde_json::json!({
+            "type": "content_block_delta",
+            "delta": {"type": "thinking_delta", "thinking": "Let me analyze this..."}
+        });
+
+        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
+
+        let received = rx.try_recv().unwrap();
+        match received {
+            AgentEvent::Thinking {
+                story_id,
+                agent_name,
+                text,
+            } => {
+                assert_eq!(story_id, "s1");
+                assert_eq!(agent_name, "coder-1");
+                assert_eq!(text, "Let me analyze this...");
+            }
+            other => panic!("Expected Thinking event, got: {other:?}"),
+        }
+    }
+
+    #[test]
+    fn stream_event_text_delta_emits_output_event() {
+        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
+        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
+
+        let event = serde_json::json!({
+            "type": "content_block_delta",
+            "delta": {"type": "text_delta", "text": "Here is the result."}
+        });
+
+        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
+
+        let received = rx.try_recv().unwrap();
+        match received {
+            AgentEvent::Output {
+                story_id,
+                agent_name,
+                text,
+            } => {
+                assert_eq!(story_id, "s1");
+                assert_eq!(agent_name, "coder-1");
+                assert_eq!(text, "Here is the result.");
+            }
+            other => panic!("Expected Output event, got: {other:?}"),
+        }
+    }
+
+    #[test]
+    fn stream_event_input_json_delta_ignored() {
+        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
+        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
+
+        let event = serde_json::json!({
+            "type": "content_block_delta",
+            "delta": {"type": "input_json_delta", "partial_json": "{\"file\":"}
+        });
+
+        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
+
+        // No event should be emitted for tool argument deltas
+        assert!(rx.try_recv().is_err());
+    }
+
+    #[test]
+    fn stream_event_non_delta_type_ignored() {
+        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
+        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
+
+        let event = serde_json::json!({
+            "type": "message_start",
+            "message": {"role": "assistant"}
+        });
+
+        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
+
+        assert!(rx.try_recv().is_err());
+    }
+}
diff --git a/server/src/agents/pty.rs b/server/src/agents/pty/runner.rs
similarity index 51%
rename from server/src/agents/pty.rs
rename to server/src/agents/pty/runner.rs
index 322df415..b36b3c3b 100644
--- a/server/src/agents/pty.rs
+++ b/server/src/agents/pty/runner.rs
@@ -1,4 +1,5 @@
-//! PTY runner — spawns agent processes in pseudo-terminals and streams their output.
+//! PTY process spawning and output loop: builds the command, drives the reader thread,
+//! and dispatches parsed JSON events to the broadcast channel.
 use std::collections::HashMap;
 use std::io::{BufRead, BufReader};
 use std::sync::{Arc, Mutex};
@@ -6,34 +7,14 @@ use std::sync::{Arc, Mutex};
 use portable_pty::{ChildKiller, CommandBuilder, PtySize, native_pty_system};
 use tokio::sync::broadcast;
 
-use super::{AgentEvent, TokenUsage};
 use crate::agent_log::AgentLogWriter;
+use crate::agents::{AgentEvent, TokenUsage};
 use crate::io::watcher::WatcherEvent;
 use crate::slog;
 use crate::slog_warn;
 
-/// Result from a PTY agent session, containing the session ID and token usage.
-pub(in crate::agents) struct PtyResult {
-    pub session_id: Option<String>,
-    pub token_usage: Option<TokenUsage>,
-}
-
-fn composite_key(story_id: &str, agent_name: &str) -> String {
-    format!("{story_id}:{agent_name}")
-}
-
-struct ChildKillerGuard {
-    killers: Arc<Mutex<HashMap<String, Box<dyn ChildKiller + Send + Sync>>>>,
-    key: String,
-}
-
-impl Drop for ChildKillerGuard {
-    fn drop(&mut self) {
-        if let Ok(mut killers) = self.killers.lock() {
-            killers.remove(&self.key);
-        }
-    }
-}
+use super::events::{emit_event, handle_agent_stream_event};
+use super::types::{ChildKillerGuard, PtyResult, composite_key};
 
 /// Spawn claude agent in a PTY and stream events through the broadcast channel.
 ///
@@ -99,79 +80,6 @@ pub(in crate::agents) async fn run_agent_pty_streaming(
     .map_err(|e| format!("Agent task panicked: {e}"))?
 }
 
-/// Dispatch a `stream_event` from Claude Code's `--include-partial-messages` output.
-///
-/// Extracts `thinking_delta` and `text_delta` from `content_block_delta` events
-/// and routes them as `AgentEvent::Thinking` and `AgentEvent::Output` respectively.
-/// This ensures thinking traces flow through the dedicated `ThinkingBlock` UI
-/// component rather than appearing as unbounded regular output.
-fn handle_agent_stream_event(
-    event: &serde_json::Value,
-    story_id: &str,
-    agent_name: &str,
-    tx: &broadcast::Sender<AgentEvent>,
-    event_log: &Mutex<Vec<AgentEvent>>,
-    log_writer: Option<&Mutex<AgentLogWriter>>,
-) {
-    let event_type = event.get("type").and_then(|t| t.as_str()).unwrap_or("");
-
-    if event_type == "content_block_delta"
-        && let Some(delta) = event.get("delta")
-    {
-        let delta_type = delta.get("type").and_then(|t| t.as_str()).unwrap_or("");
-        match delta_type {
-            "thinking_delta" => {
-                if let Some(thinking) = delta.get("thinking").and_then(|t| t.as_str()) {
-                    emit_event(
-                        AgentEvent::Thinking {
-                            story_id: story_id.to_string(),
-                            agent_name: agent_name.to_string(),
-                            text: thinking.to_string(),
-                        },
-                        tx,
-                        event_log,
-                        log_writer,
-                    );
-                }
-            }
-            "text_delta" => {
-                if let Some(text) = delta.get("text").and_then(|t| t.as_str()) {
-                    emit_event(
-                        AgentEvent::Output {
-                            story_id: story_id.to_string(),
-                            agent_name: agent_name.to_string(),
-                            text: text.to_string(),
-                        },
-                        tx,
-                        event_log,
-                        log_writer,
-                    );
-                }
-            }
-            _ => {}
-        }
-    }
-}
-
-/// Helper to send an event to broadcast, event log, and optional persistent log file.
-pub(super) fn emit_event(
-    event: AgentEvent,
-    tx: &broadcast::Sender<AgentEvent>,
-    event_log: &Mutex<Vec<AgentEvent>>,
-    log_writer: Option<&Mutex<AgentLogWriter>>,
-) {
-    if let Ok(mut log) = event_log.lock() {
-        log.push(event.clone());
-    }
-    if let Some(writer) = log_writer
-        && let Ok(mut w) = writer.lock()
-        && let Err(e) = w.write_event(&event)
-    {
-        eprintln!("[agent_log] Failed to write event to log file: {e}");
-    }
-    let _ = tx.send(event);
-}
-
 #[allow(clippy::too_many_arguments)]
 fn run_agent_pty_blocking(
     story_id: &str,
@@ -527,319 +435,3 @@ fn run_agent_pty_blocking(
         token_usage,
     })
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::agents::AgentEvent;
-    use crate::io::watcher::WatcherEvent;
-    use std::collections::HashMap;
-    use std::sync::Arc;
-
-    // ── AC1: pty detects rate_limit_event and emits RateLimitWarning ─────────
-
-    /// Verify that when a `rate_limit_event` JSON line appears in PTY output,
-    /// `run_agent_pty_streaming` sends a `WatcherEvent::RateLimitWarning` with
-    /// the correct story_id and agent_name.
-    ///
-    /// The command invoked is: `sh -p -- <script>` where `--` terminates
-    /// option parsing so the script path is treated as the operand.
-    #[tokio::test]
-    async fn rate_limit_event_json_sends_watcher_warning() {
-        use std::os::unix::fs::PermissionsExt;
-
-        let tmp = tempfile::tempdir().unwrap();
-        let script = tmp.path().join("emit_rate_limit.sh");
-        std::fs::write(
-            &script,
-            "#!/bin/sh\nprintf '%s\\n' '{\"type\":\"rate_limit_event\",\"rate_limit_info\":{\"status\":\"allowed_warning\"}}'\n",
-        )
-        .unwrap();
-        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
-
-        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
-        let (watcher_tx, mut watcher_rx) = broadcast::channel::<WatcherEvent>(16);
-        let event_log = Arc::new(Mutex::new(Vec::new()));
-        let child_killers = Arc::new(Mutex::new(HashMap::new()));
-
-        // sh -p "--" <script>: -p = privileged mode, "--" = end options,
-        // then the script path is the file operand.
-        let result = run_agent_pty_streaming(
-            "365_story_test",
-            "coder-1",
-            "sh",
-            &[script.to_string_lossy().to_string()],
-            "--",
-            "/tmp",
-            &tx,
-            &event_log,
-            None,
-            0,
-            child_killers,
-            watcher_tx,
-            None,
-        )
-        .await;
-
-        assert!(result.is_ok(), "PTY run should succeed: {:?}", result.err());
-
-        let evt = watcher_rx
-            .try_recv()
-            .expect("Expected a RateLimitWarning to be sent on watcher_tx");
-        match evt {
-            WatcherEvent::RateLimitWarning {
-                story_id,
-                agent_name,
-            } => {
-                assert_eq!(story_id, "365_story_test");
-                assert_eq!(agent_name, "coder-1");
-            }
-            other => panic!("Expected RateLimitWarning, got: {other:?}"),
-        }
-    }
-
-    /// AC1: hard block with `reset_at` emits `RateLimitHardBlock` with the
-    /// correct story_id, agent_name, and parsed reset_at timestamp.
-    #[tokio::test]
-    async fn rate_limit_hard_block_sends_watcher_hard_block_event() {
-        use std::os::unix::fs::PermissionsExt;
-
-        let tmp = tempfile::tempdir().unwrap();
-        let script = tmp.path().join("emit_hard_block.sh");
-        std::fs::write(
-            &script,
-            "#!/bin/sh\nprintf '%s\\n' '{\"type\":\"rate_limit_event\",\"rate_limit_info\":{\"status\":\"hard_block\",\"reset_at\":\"2099-01-01T12:00:00Z\"}}'\n",
-        )
-        .unwrap();
-        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
-
-        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
-        let (watcher_tx, mut watcher_rx) = broadcast::channel::<WatcherEvent>(16);
-        let event_log = Arc::new(Mutex::new(Vec::new()));
-        let child_killers = Arc::new(Mutex::new(HashMap::new()));
-
-        let result = run_agent_pty_streaming(
-            "423_story_rate_limit",
-            "coder-1",
-            "sh",
-            &[script.to_string_lossy().to_string()],
-            "--",
-            "/tmp",
-            &tx,
-            &event_log,
-            None,
-            0,
-            child_killers,
-            watcher_tx,
-            None,
-        )
-        .await;
-
-        assert!(result.is_ok(), "PTY run should succeed: {:?}", result.err());
-
-        let evt = watcher_rx
-            .try_recv()
-            .expect("Expected a RateLimitHardBlock to be sent on watcher_tx");
-        match evt {
-            WatcherEvent::RateLimitHardBlock {
-                story_id,
-                agent_name,
-                reset_at,
-            } => {
-                assert_eq!(story_id, "423_story_rate_limit");
-                assert_eq!(agent_name, "coder-1");
-                assert_eq!(
-                    reset_at.to_rfc3339(),
-                    "2099-01-01T12:00:00+00:00",
-                    "reset_at should match the parsed timestamp"
-                );
-            }
-            other => panic!("Expected RateLimitHardBlock, got: {other:?}"),
-        }
-    }
-
-    /// Bug 496: hard block WITHOUT `reset_at` must still emit `RateLimitHardBlock`
-    /// (not `RateLimitWarning`), using a default 5-minute backoff so the
-    /// auto-scheduler can set a retry timer.
-    #[tokio::test]
-    async fn rate_limit_hard_block_without_reset_at_sends_hard_block_event() {
-        use std::os::unix::fs::PermissionsExt;
-
-        let tmp = tempfile::tempdir().unwrap();
-        let script = tmp.path().join("emit_hard_block_no_reset.sh");
-        std::fs::write(
-            &script,
-            "#!/bin/sh\nprintf '%s\\n' '{\"type\":\"rate_limit_event\",\"rate_limit_info\":{\"status\":\"rejected\"}}'\n",
-        )
-        .unwrap();
-        std::fs::set_permissions(&script, std::fs::Permissions::from_mode(0o755)).unwrap();
-
-        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
-        let (watcher_tx, mut watcher_rx) = broadcast::channel::<WatcherEvent>(16);
-        let event_log = Arc::new(Mutex::new(Vec::new()));
-        let child_killers = Arc::new(Mutex::new(HashMap::new()));
-
-        let before = chrono::Utc::now();
-        let result = run_agent_pty_streaming(
-            "496_bug_hard_rate_limit",
-            "coder-1",
-            "sh",
-            &[script.to_string_lossy().to_string()],
-            "--",
-            "/tmp",
-            &tx,
-            &event_log,
-            None,
-            0,
-            child_killers,
-            watcher_tx,
-            None,
-        )
-        .await;
-        let after = chrono::Utc::now();
-
-        assert!(result.is_ok(), "PTY run should succeed: {:?}", result.err());
-
-        let evt = watcher_rx
-            .try_recv()
-            .expect("Expected a RateLimitHardBlock to be sent on watcher_tx");
-        match evt {
-            WatcherEvent::RateLimitHardBlock {
-                story_id,
-                agent_name,
-                reset_at,
-            } => {
-                assert_eq!(story_id, "496_bug_hard_rate_limit");
-                assert_eq!(agent_name, "coder-1");
-                // reset_at should be ~5 minutes from when the event fired
-                let min_expected = before + chrono::Duration::minutes(4);
-                let max_expected = after + chrono::Duration::minutes(6);
-                assert!(
-                    reset_at >= min_expected && reset_at <= max_expected,
-                    "reset_at {reset_at} should be ~5 minutes from now"
-                );
-            }
-            other => panic!("Expected RateLimitHardBlock (with default backoff), got: {other:?}"),
-        }
-    }
-
-    #[test]
-    fn test_emit_event_writes_to_log_writer() {
-        let tmp = tempfile::tempdir().unwrap();
-        let root = tmp.path();
-
-        let log_writer = AgentLogWriter::new(root, "42_story_foo", "coder-1", "sess-emit").unwrap();
-        let log_mutex = Mutex::new(log_writer);
-
-        let (tx, _rx) = broadcast::channel::<AgentEvent>(64);
-        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
-
-        let event = AgentEvent::Status {
-            story_id: "42_story_foo".to_string(),
-            agent_name: "coder-1".to_string(),
-            status: "running".to_string(),
-        };
-
-        emit_event(event, &tx, &event_log, Some(&log_mutex));
-
-        // Verify event was added to in-memory log
-        let mem_events = event_log.lock().unwrap();
-        assert_eq!(mem_events.len(), 1);
-        drop(mem_events);
-
-        // Verify event was written to the log file
-        let log_path =
-            crate::agent_log::log_file_path(root, "42_story_foo", "coder-1", "sess-emit");
-        let entries = crate::agent_log::read_log(&log_path).unwrap();
-        assert_eq!(entries.len(), 1);
-        assert_eq!(entries[0].event["type"], "status");
-        assert_eq!(entries[0].event["status"], "running");
-    }
-
-    // ── bug 167: handle_agent_stream_event routes thinking/text correctly ───
-
-    #[test]
-    fn stream_event_thinking_delta_emits_thinking_event() {
-        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
-        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
-
-        let event = serde_json::json!({
-            "type": "content_block_delta",
-            "delta": {"type": "thinking_delta", "thinking": "Let me analyze this..."}
-        });
-
-        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
-
-        let received = rx.try_recv().unwrap();
-        match received {
-            AgentEvent::Thinking {
-                story_id,
-                agent_name,
-                text,
-            } => {
-                assert_eq!(story_id, "s1");
-                assert_eq!(agent_name, "coder-1");
-                assert_eq!(text, "Let me analyze this...");
-            }
-            other => panic!("Expected Thinking event, got: {other:?}"),
-        }
-    }
-
-    #[test]
-    fn stream_event_text_delta_emits_output_event() {
-        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
-        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
-
-        let event = serde_json::json!({
-            "type": "content_block_delta",
-            "delta": {"type": "text_delta", "text": "Here is the result."}
-        });
-
-        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
-
-        let received = rx.try_recv().unwrap();
-        match received {
-            AgentEvent::Output {
-                story_id,
-                agent_name,
-                text,
-            } => {
-                assert_eq!(story_id, "s1");
-                assert_eq!(agent_name, "coder-1");
-                assert_eq!(text, "Here is the result.");
-            }
-            other => panic!("Expected Output event, got: {other:?}"),
-        }
-    }
-
-    #[test]
-    fn stream_event_input_json_delta_ignored() {
-        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
-        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
-
-        let event = serde_json::json!({
-            "type": "content_block_delta",
-            "delta": {"type": "input_json_delta", "partial_json": "{\"file\":"}
-        });
-
-        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
-
-        // No event should be emitted for tool argument deltas
-        assert!(rx.try_recv().is_err());
-    }
-
-    #[test]
-    fn stream_event_non_delta_type_ignored() {
-        let (tx, mut rx) = broadcast::channel::<AgentEvent>(64);
-        let event_log: Mutex<Vec<AgentEvent>> = Mutex::new(Vec::new());
-
-        let event = serde_json::json!({
-            "type": "message_start",
-            "message": {"role": "assistant"}
-        });
-
-        handle_agent_stream_event(&event, "s1", "coder-1", &tx, &event_log, None);
-
-        assert!(rx.try_recv().is_err());
-    }
-}
diff --git a/server/src/agents/pty/types.rs b/server/src/agents/pty/types.rs
new file mode 100644
index 00000000..b628e3b3
--- /dev/null
+++ b/server/src/agents/pty/types.rs
@@ -0,0 +1,30 @@
+//! Core types for the PTY runner: result container and process lifecycle helpers.
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
+
+use portable_pty::ChildKiller;
+
+use crate::agents::TokenUsage;
+
+/// Result from a PTY agent session, containing the session ID and token usage.
+pub(in crate::agents) struct PtyResult {
+    pub session_id: Option<String>,
+    pub token_usage: Option<TokenUsage>,
+}
+
+pub(super) fn composite_key(story_id: &str, agent_name: &str) -> String {
+    format!("{story_id}:{agent_name}")
+}
+
+pub(super) struct ChildKillerGuard {
+    pub killers: Arc<Mutex<HashMap<String, Box<dyn ChildKiller + Send + Sync>>>>,
+    pub key: String,
+}
+
+impl Drop for ChildKillerGuard {
+    fn drop(&mut self) {
+        if let Ok(mut killers) = self.killers.lock() {
+            killers.remove(&self.key);
+        }
+    }
+}