diff --git a/fs/sessionfiles.go b/fs/sessionfiles.go
index ee93d4b..2307be3 100644
--- a/fs/sessionfiles.go
+++ b/fs/sessionfiles.go
@@ -33,6 +33,14 @@ func listSessions(ctx HandlerCtx) ([]FsNodeDecl, error) {
 				return []byte(sessionEnvContent(s)), nil
 			})),
 
+			// paused — session pause status (read-only)
+			Leaf("paused", 0444, Read(func(_ HandlerCtx) ([]byte, error) {
+				if s.IsPaused() {
+					return []byte("true\n"), nil
+				}
+				return []byte("false\n"), nil
+			})),
+
 			// ctl — session control
 			Leaf("ctl", 0666,
 				Read(nopRead),
@@ -143,6 +151,10 @@ func handleSessionCtl(sess *Session, kill func(), data []byte) error {
 		}
 	case "invalidate":
 		sess.InvalidateModelsCache()
+	case "pause":
+		return sess.Pause()
+	case "resume":
+		return sess.Resume()
 	default:
 		return fmt.Errorf("unknown session ctl command: %s", cmd[0])
 	}
diff --git a/fs/types.go b/fs/types.go
index 75cfc1b..ac72c1f 100644
--- a/fs/types.go
+++ b/fs/types.go
@@ -25,6 +25,7 @@ type Session struct {
 	cancel     context.CancelFunc
 	proc       *toolsrv.Process        // toolsrv subprocess (session owns lifecycle)
 	keeper     *toolsrv.ProcessKeeper  // resilient process manager (respawns on failure)
+	paused     bool                    // true when session is paused (process stopped)
 
 	// toolsConn is the multiplexed connection to the remote tool server,
 	// shared by agent execution and 9P tool-management handlers.
@@ -227,6 +228,59 @@ func (sess *Session) Interrupt() {
 	}
 }
 
+// IsPaused returns true if the session is paused.
+func (sess *Session) IsPaused() bool {
+	sess.mu.RLock()
+	defer sess.mu.RUnlock()
+	return sess.paused
+}
+
+// Pause stops the tool server process to save resources. Tool calls will
+// return errors until Resume is called. Returns an error if already paused.
+func (sess *Session) Pause() error {
+	sess.mu.Lock()
+	defer sess.mu.Unlock()
+	if sess.paused {
+		return fmt.Errorf("session already paused")
+	}
+	// Close the keeper which kills the underlying process
+	if sess.keeper != nil {
+		sess.keeper.Close()
+	} else if sess.proc != nil {
+		sess.proc.Close()
+	}
+	// Close the connection (it will fail on next use anyway)
+	if sess.toolsConn != nil {
+		if c, ok := sess.toolsConn.(interface{ Close() }); ok {
+			c.Close()
+		}
+		sess.toolsConn = nil
+	}
+	sess.paused = true
+	return nil
+}
+
+// Resume restarts the tool server process after a Pause. Returns an error
+// if not paused or if respawn fails.
+func (sess *Session) Resume() error {
+	sess.mu.Lock()
+	defer sess.mu.Unlock()
+	if !sess.paused {
+		return fmt.Errorf("session not paused")
+	}
+	if sess.keeper == nil {
+		return fmt.Errorf("no process keeper available")
+	}
+	// Dial triggers respawn if needed
+	conn, err := sess.keeper.Dial()
+	if err != nil {
+		return fmt.Errorf("resume failed: %w", err)
+	}
+	sess.toolsConn = conn
+	sess.paused = false
+	return nil
+}
+
 // --- AgentLog methods ---
 
 // AppendLog appends data to the agent's log and bumps the version.