fix: make env refresh tolerant of unsupported service hosts

cli/azd/cmd/env.go

@@ -1151,12 +1151,19 @@ func (ef *envRefreshAction) Run(ctx context.Context) (*actions.ActionResult, err
 		Title: fmt.Sprintf("Refreshing environment %s (azd env refresh)", ef.env.Name()),
 	})
 
+	// Initialize services, skipping any with unsupported hosts (e.g., extension-provided hosts
+	// that are not currently loaded). Env refresh only needs infrastructure outputs from Azure;
+	// services with unsupported hosts simply won't receive the environment-updated event.
 	if err := ef.projectManager.Initialize(ctx, ef.projectConfig); err != nil {
-		return nil, err
+		if !hasUnsupportedHostError(err) {
+			return nil, err
+		}
 	}
 
 	if err := ef.projectManager.EnsureAllTools(ctx, ef.projectConfig, nil); err != nil {
-		return nil, err
+		if !hasUnsupportedHostError(err) {
+			return nil, err
+		}
 	}
 
 	infra, err := ef.importManager.ProjectInfrastructure(ctx, ef.projectConfig)
@@ -1253,6 +1260,14 @@ func (ef *envRefreshAction) Run(ctx context.Context) (*actions.ActionResult, err
 	}, nil
 }
 
+// hasUnsupportedHostError reports whether err (or any error in its chain) is caused by
+// an unsupported service host. This lets env refresh continue when extension-provided hosts
+// (e.g., azure.ai.agent) are not loaded.
+func hasUnsupportedHostError(err error) bool {
+	_, ok := errors.AsType[*project.UnsupportedServiceHostError](err)
+	return ok
+}
+
 func newEnvGetValuesFlags(cmd *cobra.Command, global *internal.GlobalCommandOptions) *envGetValuesFlags {
 	flags := &envGetValuesFlags{}
 	flags.Bind(cmd.Flags(), global)

cli/azd/cmd/env_test.go

@@ -4,8 +4,11 @@
 package cmd
 
 import (
+	"fmt"
 	"testing"
 
+	"github.com/azure/azure-dev/cli/azd/internal"
+	"github.com/azure/azure-dev/cli/azd/pkg/project"
 	"github.com/spf13/cobra"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -170,3 +173,59 @@ func TestNewEnvConfigUnsetCmd(t *testing.T) {
 	require.Equal(t, "unset <path>", cmd.Use)
 	require.NotEmpty(t, cmd.Short)
 }
+
+func TestHasUnsupportedHostError(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name     string
+		err      error
+		expected bool
+	}{
+		{
+			name:     "nil error",
+			err:      nil,
+			expected: false,
+		},
+		{
+			name:     "unrelated error",
+			err:      assert.AnError,
+			expected: false,
+		},
+		{
+			name: "direct UnsupportedServiceHostError",
+			err: &project.UnsupportedServiceHostError{
+				Host:        "azure.ai.agent",
+				ServiceName: "agent",
+			},
+			expected: true,
+		},
+		{
+			name: "wrapped UnsupportedServiceHostError",
+			err: fmt.Errorf("initializing service 'agent', %w", &project.UnsupportedServiceHostError{
+				Host:        "azure.ai.agent",
+				ServiceName: "agent",
+			}),
+			expected: true,
+		},
+		{
+			name: "wrapped in ErrorWithSuggestion",
+			err: fmt.Errorf("getting service target: %w", &internal.ErrorWithSuggestion{
+				Err: &project.UnsupportedServiceHostError{
+					Host:        "azure.ai.agent",
+					ServiceName: "agent",
+				},
+				Suggestion: "install an extension",
+			}),
+			expected: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			got := hasUnsupportedHostError(tt.err)
+			assert.Equal(t, tt.expected, got)
+		})
+	}
+}