feat(cli): add verbose logging option for CLI commands

* Introduced a new flag `--verbose` to enable detailed logging.
* Implemented logging for connection events in SSE and stdio commands.
* Added a utility function to handle verbose logging.

cmd/amcs-cli/cmd/root.go

@@ -17,6 +17,7 @@ var (
 	serverFlag string
 	tokenFlag  string
 	outputFlag string
+	verbose    bool
 	cfg        Config
 )
 
@@ -42,6 +43,7 @@ func init() {
 	rootCmd.PersistentFlags().StringVar(&serverFlag, "server", "", "AMCS server URL")
 	rootCmd.PersistentFlags().StringVar(&tokenFlag, "token", "", "AMCS bearer token")
 	rootCmd.PersistentFlags().StringVar(&outputFlag, "output", "json", "Output format: json or yaml")
+	rootCmd.PersistentFlags().BoolVar(&verbose, "verbose", false, "Enable verbose logging to stderr")
 }
 
 func loadConfig() error {
@@ -122,6 +124,7 @@ func connectRemote(ctx context.Context) (*mcp.ClientSession, error) {
 	if err := requireServer(); err != nil {
 		return nil, err
 	}
+	verboseLogf("connecting to %s", endpointURL())
 	client := mcp.NewClient(&mcp.Implementation{Name: "amcs-cli", Version: "0.0.1"}, nil)
 	transport := &mcp.StreamableClientTransport{
 		Endpoint:   endpointURL(),
@@ -133,5 +136,13 @@ func connectRemote(ctx context.Context) (*mcp.ClientSession, error) {
 	if err != nil {
 		return nil, fmt.Errorf("connect to AMCS server: %w", err)
 	}
+	verboseLogf("connected to %s", endpointURL())
 	return session, nil
 }
+
+func verboseLogf(format string, args ...any) {
+	if !verbose {
+		return
+	}
+	_, _ = fmt.Fprintf(os.Stderr, "[amcs-cli] "+format+"\n", args...)
+}

cmd/amcs-cli/cmd/root_test.go

@@ -0,0 +1,31 @@
+package cmd
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestBearerTransportFormatsBearerToken(t *testing.T) {
+	const want = "Bearer X"
+
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if got := r.Header.Get("Authorization"); got != want {
+			t.Fatalf("Authorization header = %q, want %q", got, want)
+		}
+		w.WriteHeader(http.StatusNoContent)
+	}))
+	defer ts.Close()
+
+	client := &http.Client{Transport: &bearerTransport{token: "X"}}
+	req, err := http.NewRequest(http.MethodGet, ts.URL, nil)
+	if err != nil {
+		t.Fatalf("NewRequest() error = %v", err)
+	}
+
+	res, err := client.Do(req)
+	if err != nil {
+		t.Fatalf("client.Do() error = %v", err)
+	}
+	_ = res.Body.Close()
+}

cmd/amcs-cli/cmd/sse.go

@@ -29,11 +29,13 @@ var sseCmd = &cobra.Command{
 		connectCtx, cancel := context.WithTimeout(ctx, 30*time.Second)
 		defer cancel()
 
+		verboseLogf("connecting to SSE endpoint %s", sseEndpointURL())
 		remote, err := client.Connect(connectCtx, transport, nil)
 		if err != nil {
 			return fmt.Errorf("connect to AMCS SSE endpoint: %w", err)
 		}
 		defer func() { _ = remote.Close() }()
+		verboseLogf("connected to SSE endpoint %s", sseEndpointURL())
 
 		tools, err := remote.ListTools(ctx, nil)
 		if err != nil {
@@ -67,6 +69,8 @@ var sseCmd = &cobra.Command{
 			return fmt.Errorf("start stdio bridge: %w", err)
 		}
 		defer func() { _ = session.Close() }()
+		verboseLogf("sse stdio bridge ready")
+		verboseLogf("waiting for MCP commands on stdin")
 
 		<-ctx.Done()
 		return nil

cmd/amcs-cli/cmd/stdio.go

@@ -51,6 +51,8 @@ var stdioCmd = &cobra.Command{
 			return fmt.Errorf("start stdio bridge: %w", err)
 		}
 		defer func() { _ = session.Close() }()
+		verboseLogf("stdio bridge connected to remote AMCS and ready")
+		verboseLogf("waiting for MCP commands on stdin")
 
 		<-ctx.Done()
 		return nil