fix: enforce json output for az monitor metrics and aks tools

internal/components/azaks/executor.go

@@ -7,6 +7,7 @@ import (
 	"github.com/Azure/aks-mcp/internal/command"
 	"github.com/Azure/aks-mcp/internal/config"
 	"github.com/Azure/aks-mcp/internal/security"
+	"github.com/google/shlex"
 )
 
 // AksOperationsExecutor handles execution of AKS operations
@@ -31,6 +32,12 @@ func (e *AksOperationsExecutor) Execute(params map[string]interface{}, cfg *conf
 		args = ""
 	}
 
+	// Ensure az CLI returns JSON unless caller already specified an output format
+	args, err := ensureOutputFormatArgs(args)
+	if err != nil {
+		return "", err
+	}
+
 	// Validate access for this operation
 	if err := ValidateOperationAccess(operation, cfg); err != nil {
 		return "", err
@@ -91,3 +98,31 @@ func (e *AksOperationsExecutor) ExecuteSpecificCommand(operation string, params
 
 	return e.Execute(newParams, cfg)
 }
+
+// ensureOutputFormatArgs adds --output json when no explicit output format is provided
+func ensureOutputFormatArgs(args string) (string, error) {
+	if strings.TrimSpace(args) == "" {
+		return "--output json", nil
+	}
+
+	parsedArgs, err := shlex.Split(args)
+	if err != nil {
+		return "", fmt.Errorf("parsing args: %w", err)
+	}
+
+	for _, token := range parsedArgs {
+		lowerToken := strings.ToLower(token)
+		switch {
+		case lowerToken == "--output":
+			return args, nil
+		case strings.HasPrefix(lowerToken, "--output="):
+			return args, nil
+		case lowerToken == "-o":
+			return args, nil
+		case strings.HasPrefix(lowerToken, "-o") && len(lowerToken) > 2:
+			return args, nil
+		}
+	}
+
+	return args + " --output json", nil
+}

internal/components/azaks/executor_test.go

@@ -0,0 +1,68 @@
+package azaks
+
+import "testing"
+
+func TestEnsureOutputFormatArgs(t *testing.T) {
+	tests := []struct {
+		name    string
+		input   string
+		want    string
+		wantErr bool
+	}{
+		{
+			name:  "empty args",
+			input: "",
+			want:  "--output json",
+		},
+		{
+			name:  "already has long output flag",
+			input: "--resource-group rg --output table",
+			want:  "--resource-group rg --output table",
+		},
+		{
+			name:  "already has long output flag equals",
+			input: "--output=json --resource-group rg",
+			want:  "--output=json --resource-group rg",
+		},
+		{
+			name:  "already has short output flag",
+			input: "-o json --name test",
+			want:  "-o json --name test",
+		},
+		{
+			name:  "already has short compact output flag",
+			input: "-ojson --name test",
+			want:  "-ojson --name test",
+		},
+		{
+			name:  "no output flag appends json",
+			input: "--name test --resource-group rg",
+			want:  "--name test --resource-group rg --output json",
+		},
+		{
+			name:    "malformed args returns error",
+			input:   "--name \"missing-end",
+			wantErr: true,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := ensureOutputFormatArgs(tc.input)
+			if tc.wantErr {
+				if err == nil {
+					t.Fatalf("expected error, got none")
+				}
+				return
+			}
+
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+
+			if got != tc.want {
+				t.Fatalf("got %q, want %q", got, tc.want)
+			}
+		})
+	}
+}

internal/components/monitor/handlers.go

@@ -329,6 +329,8 @@ func handleMetricsOperation(params map[string]interface{}, cfg *config.ConfigDat
 		args = append(args, fmt.Sprintf("%v", value))
 	}
 
+	args = ensureOutputArg(args)
+
 	// Map query type to command
 	baseCommand, err := MapMetricsQueryTypeToCommand(queryType)
 	if err != nil {
@@ -387,3 +389,22 @@ func handleLogsOperation(params map[string]interface{}, azClient *azureclient.Az
 	// Use existing control plane logs handler
 	return diagnostics.GetControlPlaneLogsHandler(azClient, cfg).Handle(mergedParams, cfg)
 }
+
+// ensureOutputArg appends --output json when no explicit output flag is present
+func ensureOutputArg(args []string) []string {
+	for _, arg := range args {
+		lower := strings.ToLower(arg)
+		switch {
+		case lower == "--output":
+			return args
+		case strings.HasPrefix(lower, "--output="):
+			return args
+		case lower == "-o":
+			return args
+		case strings.HasPrefix(lower, "-o") && len(lower) > 2:
+			return args
+		}
+	}
+
+	return append(args, "--output", "json")
+}

internal/components/monitor/handlers_test.go

@@ -4,6 +4,54 @@ import (
 	"testing"
 )
 
+func TestEnsureOutputArg(t *testing.T) {
+	tests := []struct {
+		name string
+		in   []string
+		out  []string
+	}{
+		{
+			name: "appends when missing",
+			in:   []string{"--name", "test"},
+			out:  []string{"--name", "test", "--output", "json"},
+		},
+		{
+			name: "no change with long flag",
+			in:   []string{"--name", "test", "--output", "table"},
+			out:  []string{"--name", "test", "--output", "table"},
+		},
+		{
+			name: "no change with equals",
+			in:   []string{"--output=json", "--name", "test"},
+			out:  []string{"--output=json", "--name", "test"},
+		},
+		{
+			name: "no change with short flag",
+			in:   []string{"-o", "table", "--name", "test"},
+			out:  []string{"-o", "table", "--name", "test"},
+		},
+		{
+			name: "no change with combined short flag",
+			in:   []string{"-otable", "--name", "test"},
+			out:  []string{"-otable", "--name", "test"},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			result := ensureOutputArg(tc.in)
+			if len(result) != len(tc.out) {
+				t.Fatalf("length mismatch: got %d, want %d", len(result), len(tc.out))
+			}
+			for i := range tc.out {
+				if result[i] != tc.out[i] {
+					t.Fatalf("index %d mismatch: got %q, want %q", i, result[i], tc.out[i])
+				}
+			}
+		})
+	}
+}
+
 func TestHandleAppInsightsQuery_ValidParameters(t *testing.T) {
 	params := map[string]interface{}{
 		"subscription_id":   "test-subscription",