diff --git a/commands/cc_statusline.go b/commands/cc_statusline.go
index bf1dfa8..ec9b5f7 100644
--- a/commands/cc_statusline.go
+++ b/commands/cc_statusline.go
@@ -66,6 +66,24 @@ func commandCCStatusline(c *cli.Context) error {
 	var result ccStatuslineResult
 	config, err := configService.ReadConfigFile(ctx)
 	if err == nil {
+		// Send session-project mapping via daemon socket (fire-and-forget, ~1ms)
+		if data.SessionID != "" {
+			projectPath := ""
+			if data.Workspace != nil {
+				projectPath = data.Workspace.CurrentDir
+				if projectPath == "" {
+					projectPath = data.Workspace.ProjectDir
+				}
+			}
+			if projectPath != "" {
+				socketPath := config.SocketPath
+				if socketPath == "" {
+					socketPath = model.DefaultSocketPath
+				}
+				daemon.SendSessionProject(socketPath, data.SessionID, projectPath)
+			}
+		}
+
 		result = getDaemonInfoWithFallback(ctx, config, data.Cwd)
 	}
 
diff --git a/daemon/client.go b/daemon/client.go
index 0b9d4cc..77a146f 100644
--- a/daemon/client.go
+++ b/daemon/client.go
@@ -51,6 +51,25 @@ func SendLocalDataToSocket(
 	return nil
 }
 
+// SendSessionProject sends a session-to-project mapping to the daemon (fire-and-forget)
+func SendSessionProject(socketPath string, sessionID, projectPath string) {
+	conn, err := net.DialTimeout("unix", socketPath, 10*time.Millisecond)
+	if err != nil {
+		return
+	}
+	defer conn.Close()
+
+	msg := SocketMessage{
+		Type: SocketMessageTypeSessionProject,
+		Payload: SessionProjectRequest{
+			SessionID:   sessionID,
+			ProjectPath: projectPath,
+		},
+	}
+
+	json.NewEncoder(conn).Encode(msg)
+}
+
 // RequestCCInfo requests CC info (cost data and git info) from the daemon
 func RequestCCInfo(socketPath string, timeRange CCInfoTimeRange, workingDir string, timeout time.Duration) (*CCInfoResponse, error) {
 	conn, err := net.DialTimeout("unix", socketPath, timeout)
diff --git a/daemon/socket.go b/daemon/socket.go
index 17ada67..e7cfde1 100644
--- a/daemon/socket.go
+++ b/daemon/socket.go
@@ -1,6 +1,7 @@
 package daemon
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"log/slog"
@@ -17,12 +18,18 @@ import (
 type SocketMessageType string
 
 const (
-	SocketMessageTypeSync      SocketMessageType = "sync"
-	SocketMessageTypeHeartbeat SocketMessageType = "heartbeat"
-	SocketMessageTypeStatus    SocketMessageType = "status"
-	SocketMessageTypeCCInfo    SocketMessageType = "cc_info"
+	SocketMessageTypeSync           SocketMessageType = "sync"
+	SocketMessageTypeHeartbeat      SocketMessageType = "heartbeat"
+	SocketMessageTypeStatus         SocketMessageType = "status"
+	SocketMessageTypeCCInfo         SocketMessageType = "cc_info"
+	SocketMessageTypeSessionProject SocketMessageType = "session_project"
 )
 
+type SessionProjectRequest struct {
+	SessionID   string `json:"sessionId"`
+	ProjectPath string `json:"projectPath"`
+}
+
 type CCInfoTimeRange string
 
 const (
@@ -179,6 +186,15 @@ func (p *SocketHandler) handleConnection(conn net.Conn) {
 		encoder.Encode(map[string]string{"status": "ok"})
 	case SocketMessageTypeCCInfo:
 		p.handleCCInfo(conn, msg)
+	case SocketMessageTypeSessionProject:
+		if payload, ok := msg.Payload.(map[string]interface{}); ok {
+			sessionID, _ := payload["sessionId"].(string)
+			projectPath, _ := payload["projectPath"].(string)
+			if sessionID != "" && projectPath != "" {
+				go model.SendSessionProjectUpdate(context.Background(), *p.config, sessionID, projectPath)
+				slog.Debug("session_project update dispatched", slog.String("sessionId", sessionID))
+			}
+		}
 	default:
 		slog.Error("Unknown message type:", slog.String("messageType", string(msg.Type)))
 	}
diff --git a/model/api_session_project.go b/model/api_session_project.go
new file mode 100644
index 0000000..ed5e6f8
--- /dev/null
+++ b/model/api_session_project.go
@@ -0,0 +1,39 @@
+package model
+
+import (
+	"context"
+	"net/http"
+	"time"
+)
+
+type sessionProjectRequest struct {
+	SessionID   string `json:"session_id"`
+	ProjectPath string `json:"project_path"`
+}
+
+type sessionProjectResponse struct{}
+
+// SendSessionProjectUpdate sends a session-to-project path mapping to the server
+func SendSessionProjectUpdate(ctx context.Context, config ShellTimeConfig, sessionID, projectPath string) error {
+	ctx, span := modelTracer.Start(ctx, "session_project.send")
+	defer span.End()
+
+	var resp sessionProjectResponse
+	err := SendHTTPRequestJSON(HTTPRequestOptions[*sessionProjectRequest, sessionProjectResponse]{
+		Context: ctx,
+		Endpoint: Endpoint{
+			APIEndpoint: config.APIEndpoint,
+			Token:       config.Token,
+		},
+		Method:  http.MethodPost,
+		Path:    "/api/v1/cc/session-project",
+		Payload: &sessionProjectRequest{
+			SessionID:   sessionID,
+			ProjectPath: projectPath,
+		},
+		Response: &resp,
+		Timeout:  5 * time.Second,
+	})
+
+	return err
+}
diff --git a/model/cc_statusline_types.go b/model/cc_statusline_types.go
index 0278d47..53b1927 100644
--- a/model/cc_statusline_types.go
+++ b/model/cc_statusline_types.go
@@ -8,6 +8,14 @@ type CCStatuslineInput struct {
 	ContextWindow CCStatuslineContextWindow `json:"context_window"`
 	Cwd           string                    `json:"cwd"`
 	Version       string                    `json:"version"`
+	SessionID     string                    `json:"session_id"`
+	Workspace     *CCStatuslineWorkspace    `json:"workspace"`
+}
+
+// CCStatuslineWorkspace represents workspace information from Claude Code
+type CCStatuslineWorkspace struct {
+	CurrentDir string `json:"current_dir"`
+	ProjectDir string `json:"project_dir"`
 }
 
 // CCStatuslineModel represents model information