Only install skills for clients detected on the system

pkg/api/server.go

@@ -772,9 +772,13 @@ func (a *clientPathAdapter) GetSkillPath(clientType, skillName string, scope ski
 
 func (a *clientPathAdapter) ListSkillSupportingClients() []string {
 	clients := a.cm.ListSkillSupportingClients()
-	result := make([]string, len(clients))
-	for i, c := range clients {
-		result[i] = string(c)
+	var result []string
+	for _, c := range clients {
+		if a.cm.IsClientInstalled(c) {
+			result = append(result, string(c))
+		} else {
+			slog.Debug("skipping client for skill install: not detected on system", "client", c)
+		}
 	}
 	return result
 }

pkg/client/discovery.go

@@ -77,6 +77,24 @@ type ClientAppStatus struct {
 	SupportsSkills bool `json:"supports_skills"`
 }
 
+// IsClientInstalled reports whether the given client appears to be installed on
+// the current system. Detection is based on the presence of the client's
+// configuration directory (or settings file when no relative path is defined).
+func (cm *ClientManager) IsClientInstalled(clientType ClientApp) bool {
+	cfg := cm.lookupClientAppConfig(clientType)
+	if cfg == nil {
+		return false
+	}
+	var pathToCheck string
+	if len(cfg.RelPath) == 0 {
+		pathToCheck = filepath.Join(cm.homeDir, cfg.SettingsFile)
+	} else {
+		pathToCheck = buildConfigDirectoryPath(cfg.RelPath, cfg.PlatformPrefix, []string{cm.homeDir})
+	}
+	_, err := os.Stat(pathToCheck)
+	return err == nil
+}
+
 // GetClientStatus returns the status of all supported MCP clients using this manager's dependencies
 func (cm *ClientManager) GetClientStatus(ctx context.Context) ([]ClientAppStatus, error) {
 	var statuses []ClientAppStatus
@@ -106,26 +124,10 @@ func (cm *ClientManager) GetClientStatus(ctx context.Context) ([]ClientAppStatus
 	for _, cfg := range cm.clientIntegrations {
 		status := ClientAppStatus{
 			ClientType:     cfg.ClientType,
-			Installed:      false, // start with assuming client is not installed
+			Installed:      cm.IsClientInstalled(cfg.ClientType),
 			Registered:     registeredClients[string(cfg.ClientType)],
 			SupportsSkills: cfg.SupportsSkills,
 		}
-
-		// Determine path to check based on configuration
-		var pathToCheck string
-		if len(cfg.RelPath) == 0 {
-			// If RelPath is empty, look at just the settings file
-			pathToCheck = filepath.Join(cm.homeDir, cfg.SettingsFile)
-		} else {
-			// Otherwise build the directory path using RelPath
-			pathToCheck = buildConfigDirectoryPath(cfg.RelPath, cfg.PlatformPrefix, []string{cm.homeDir})
-		}
-
-		// Check if the path exists
-		if _, err := os.Stat(pathToCheck); err == nil {
-			status.Installed = true
-		}
-
 		statuses = append(statuses, status)
 	}
 

pkg/client/discovery_test.go

@@ -200,6 +200,66 @@ func TestGetClientStatus_Sorting(t *testing.T) {
 	}
 }
 
+func TestIsClientInstalled(t *testing.T) {
+	t.Parallel()
+
+	tempHome := t.TempDir()
+
+	// Create a .claude.json file (simulates ClaudeCode installed)
+	_, err := os.Create(filepath.Join(tempHome, ".claude.json"))
+	require.NoError(t, err)
+
+	// Create a .cursor directory (simulates Cursor installed via RelPath)
+	err = os.Mkdir(filepath.Join(tempHome, ".cursor"), 0700)
+	require.NoError(t, err)
+
+	// VSCode path (.config/Code/User) is intentionally not created
+
+	clientIntegrations := []clientAppConfig{
+		{
+			ClientType:   ClaudeCode,
+			SettingsFile: ".claude.json",
+			RelPath:      []string{}, // file directly in home dir
+		},
+		{
+			ClientType:   Cursor,
+			SettingsFile: "mcp.json",
+			RelPath:      []string{".cursor"}, // directory in home dir
+		},
+		{
+			ClientType:   VSCode,
+			SettingsFile: "mcp.json",
+			RelPath:      []string{".config", "Code", "User"}, // not created
+		},
+		{
+			// unknown client, no config
+			ClientType:   ClientApp("nonexistent"),
+			SettingsFile: "settings.json",
+			RelPath:      []string{".nonexistent"},
+		},
+	}
+
+	manager := NewTestClientManager(tempHome, nil, clientIntegrations, nil)
+
+	tests := []struct {
+		name       string
+		clientType ClientApp
+		want       bool
+	}{
+		{name: "ClaudeCode settings file present", clientType: ClaudeCode, want: true},
+		{name: "Cursor directory present", clientType: Cursor, want: true},
+		{name: "VSCode directory absent", clientType: VSCode, want: false},
+		{name: "client not in integrations", clientType: ClientApp("not-registered"), want: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			assert.Equal(t, tt.want, manager.IsClientInstalled(tt.clientType))
+		})
+	}
+}
+
 func TestGetClientStatus_WithGroups(t *testing.T) {
 	t.Parallel()
 

pkg/skills/skillsvc/skillsvc.go

@@ -1448,8 +1448,9 @@ func (s *service) resolveAndValidateClients(
 		clients := s.pathResolver.ListSkillSupportingClients()
 		if len(clients) == 0 {
 			return nil, nil, httperr.WithCode(
-				errors.New("no skill-supporting clients configured"),
-				http.StatusInternalServerError,
+				errors.New("no supported clients detected on this system; "+
+					"use --clients to target a specific client explicitly"),
+				http.StatusBadRequest,
 			)
 		}
 		requested = clients

test/e2e/api_helpers.go

@@ -11,6 +11,7 @@ import (
 	"net/http"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"time"
@@ -78,6 +79,11 @@ func NewServer(config *ServerConfig) (*Server, error) {
 		tempHome = GinkgoT().TempDir()
 	}
 
+	// Create a stub claude-code settings file so that at least one skill-supporting
+	// client is detected as installed. Without this, installs that omit --clients
+	// would fail because no client config paths exist in the temp home dir.
+	_ = os.WriteFile(filepath.Join(tempHome, ".claude.json"), []byte("{}"), 0600)
+
 	ctx, cancel := context.WithCancel(context.Background())
 
 	// Create string builders to capture output