diff --git a/docs/extending/SOCKET_API.md b/docs/extending/SOCKET_API.md
index 5d663a7..0461021 100644
--- a/docs/extending/SOCKET_API.md
+++ b/docs/extending/SOCKET_API.md
@@ -13,6 +13,7 @@ list_agents
 complete_agent
 restart_agent
 trigger_cleanup
+trigger_refresh
 repair_state
 get_repo_config
 update_repo_config
@@ -49,6 +50,7 @@ Each command below matches a `case` in `handleRequest`.
 | `complete_agent` | Mark agent ready for cleanup | `repo`, `name`, `summary`, `failure_reason` |
 | `restart_agent` | Restart a persistent agent | `repo`, `name` |
 | `trigger_cleanup` | Force cleanup cycle | none |
+| `trigger_refresh` | Force worktree refresh cycle | none |
 | `repair_state` | Run state repair routine | none |
 | `get_repo_config` | Get merge-queue / pr-shepherd config | `repo` |
 | `update_repo_config` | Update repo config | `repo`, `config` (JSON object) |
@@ -644,6 +646,27 @@ class MulticlaudeClient {
 }
 ```
 
+#### trigger_refresh
+
+**Description:** Trigger immediate worktree refresh for all agents (syncs with main branch)
+
+**Request:**
+```json
+{
+  "command": "trigger_refresh"
+}
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "data": "Worktree refresh triggered"
+}
+```
+
+**Note:** Refresh runs asynchronously in the background.
+
 #### repair_state
 
 **Description:** Repair inconsistent state (equivalent to `multiclaude repair`)
diff --git a/internal/cli/cli.go b/internal/cli/cli.go
index 3e06628..11acc6b 100644
--- a/internal/cli/cli.go
+++ b/internal/cli/cli.go
@@ -13,6 +13,8 @@ import (
 	"strings"
 	"time"
 
+	"github.com/google/uuid"
+
 	"github.com/dlorenc/multiclaude/internal/agents"
 	"github.com/dlorenc/multiclaude/internal/bugreport"
 	"github.com/dlorenc/multiclaude/internal/daemon"
@@ -5538,14 +5540,25 @@ func (c *CLI) restartClaude(args []string) error {
 
 	// Build the command
 	var cmdArgs []string
+	sessionID := agent.SessionID
 	if hasHistory {
 		// Session has history - use --resume to continue
-		cmdArgs = []string{"--resume", agent.SessionID}
-		fmt.Printf("Resuming Claude session %s...\n", agent.SessionID)
+		cmdArgs = []string{"--resume", sessionID}
+		fmt.Printf("Resuming Claude session %s...\n", sessionID)
 	} else {
-		// New session - use --session-id
-		cmdArgs = []string{"--session-id", agent.SessionID}
-		fmt.Printf("Starting new Claude session %s...\n", agent.SessionID)
+		// No history - generate a new session ID to avoid "already in use" errors
+		// This can happen when Claude exits abnormally or the previous session
+		// was started but never used
+		sessionID = uuid.New().String()
+		cmdArgs = []string{"--session-id", sessionID}
+		fmt.Printf("Starting new Claude session %s...\n", sessionID)
+
+		// Update agent with new session ID
+		agent.SessionID = sessionID
+		if err := st.UpdateAgent(repoName, agentName, agent); err != nil {
+			fmt.Printf("Warning: failed to save new session ID: %v\n", err)
+			// Continue anyway - the session will work, just won't persist
+		}
 	}
 
 	// Add common flags