Read Codex rate limits at startup so Status always shows them

internal/codex/session.go

@@ -116,6 +116,45 @@ type Session struct {
 }
 
 func Start(ctx context.Context, opts Options) (*Session, error) {
+	s, err := spawn(opts)
+	if err != nil {
+		return nil, err
+	}
+
+	err = s.open(ctx, opts)
+	if err != nil {
+		s.Close()
+		return nil, err
+	}
+	return s, nil
+}
+
+func ReadRateLimits(ctx context.Context, cwd string, env []string) (RateLimitSnapshot, error) {
+	s, err := spawn(Options{Cwd: cwd, Env: env})
+	if err != nil {
+		return RateLimitSnapshot{}, err
+	}
+	defer s.Close()
+
+	go func() {
+		for range s.events {
+		}
+	}()
+
+	err = s.initialize(ctx)
+	if err != nil {
+		return RateLimitSnapshot{}, err
+	}
+
+	resp := GetAccountRateLimitsResponse{}
+	err = s.Call(ctx, MethodAccountRateLimitsRead, GetAccountRateLimitsParams{ExcludeResetCreditDetails: true}, &resp)
+	if err != nil {
+		return RateLimitSnapshot{}, fmt.Errorf("read rate limits: %w", err)
+	}
+	return resp.RateLimits, nil
+}
+
+func spawn(opts Options) (*Session, error) {
 	cmd := exec.Command("codex", "app-server", "-c", "check_for_update_on_startup=false")
 	cmd.Dir = opts.Cwd
 	cmd.Stderr = os.Stderr
@@ -138,12 +177,6 @@ func Start(ctx context.Context, opts Options) (*Session, error) {
 
 	s := newSession(opts, stdin, stdout)
 	s.cmd = cmd
-
-	err = s.open(ctx, opts)
-	if err != nil {
-		s.Close()
-		return nil, err
-	}
 	return s, nil
 }
 
@@ -167,20 +200,7 @@ func newSession(opts Options, stdin io.WriteCloser, stdout io.Reader) *Session {
 }
 
 func (s *Session) open(ctx context.Context, opts Options) error {
-	init := InitializeResponse{}
-	err := s.Call(ctx, MethodInitialize, InitializeParams{
-		ClientInfo:   ClientInfo{Name: "byre", Title: "byre", Version: "0.0.0"},
-		Capabilities: &InitializeCapabilities{ExperimentalApi: true},
-	}, &init)
-	if err != nil {
-		return fmt.Errorf("initialize: %w", err)
-	}
-
-	s.stateMu.Lock()
-	s.userAgent = init.UserAgent
-	s.stateMu.Unlock()
-
-	err = s.notify("initialized", nil)
+	err := s.initialize(ctx)
 	if err != nil {
 		return err
 	}
@@ -239,6 +259,23 @@ func (s *Session) open(ctx context.Context, opts Options) error {
 	return nil
 }
 
+func (s *Session) initialize(ctx context.Context) error {
+	init := InitializeResponse{}
+	err := s.Call(ctx, MethodInitialize, InitializeParams{
+		ClientInfo:   ClientInfo{Name: "byre", Title: "byre", Version: "0.0.0"},
+		Capabilities: &InitializeCapabilities{ExperimentalApi: true},
+	}, &init)
+	if err != nil {
+		return fmt.Errorf("initialize: %w", err)
+	}
+
+	s.stateMu.Lock()
+	s.userAgent = init.UserAgent
+	s.stateMu.Unlock()
+
+	return s.notify("initialized", nil)
+}
+
 func stdioConfig(servers []mcp.Stdio) map[string]any {
 	if len(servers) == 0 {
 		return nil