refactor: Simplify remote URL templating using 'variables' array

Replace the complex arguments/environmentVariables approach with a clean
'variables' array that directly maps variable names to {curly_braces} in URLs.

Key changes:
- Replace 'arguments' and 'environmentVariables' with single 'variables' array
- Update Transport struct to include Variables field
- Fix Go validators to support template variables in remote URLs
- Update example to use path-based templating for better namespace validation
- All validation and schema checks now pass

This provides a much cleaner API: variables array contains KeyValueInput
objects where the 'name' field maps directly to {variable_name} in the URL.

Example:
{
  "url": "https://api.example.github.io/mcp/{tenant_id}",
  "variables": [{"name": "tenant_id", "description": "Tenant ID", "isRequired": true}]
}

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: tadasant

cmd/publisher/commands/init.go

@@ -309,7 +309,7 @@ func createServerJSON(
 			URL:    repoURL,
 			Source: repoSource,
 		},
-		Version: version,
+		Version:  version,
 		Packages: []model.Package{pkg},
 	}
 }

cmd/publisher/commands/logout.go

@@ -13,7 +13,7 @@ func LogoutCommand() error {
 	}
 
 	tokenPath := filepath.Join(homeDir, TokenFileName)
-	
+
 	// Check if token file exists
 	if _, err := os.Stat(tokenPath); os.IsNotExist(err) {
 		_, _ = fmt.Fprintln(os.Stdout, "Not logged in")
@@ -30,7 +30,7 @@ func LogoutCommand() error {
 		".mcpregistry_github_token",
 		".mcpregistry_registry_token",
 	}
-	
+
 	for _, file := range legacyFiles {
 		path := filepath.Join(homeDir, file)
 		if _, err := os.Stat(path); err == nil {
@@ -40,4 +40,4 @@ func LogoutCommand() error {
 
 	_, _ = fmt.Fprintln(os.Stdout, "✓ Successfully logged out")
 	return nil
-}
+}

cmd/publisher/main.go

@@ -67,4 +67,4 @@ func printUsage() {
 	_, _ = fmt.Fprintln(os.Stdout, "  publish       Publish server.json to the registry")
 	_, _ = fmt.Fprintln(os.Stdout)
 	_, _ = fmt.Fprintln(os.Stdout, "Use 'mcp-publisher <command> --help' for more information about a command.")
-}
+}

deploy/pkg/k8s/ingress.go

@@ -51,7 +51,7 @@ func SetupIngressController(ctx *pulumi.Context, cluster *providers.ProviderInfo
 		Values: pulumi.Map{
 			"controller": pulumi.Map{
 				"service": pulumi.Map{
-					"type": serviceType,
+					"type":        serviceType,
 					"annotations": pulumi.Map{},
 				},
 				"config": pulumi.Map{

deploy/pkg/providers/gcp/provider.go

@@ -22,19 +22,19 @@ type Provider struct{}
 // createGCPProvider creates a GCP provider with explicit credentials if configured
 func createGCPProvider(ctx *pulumi.Context, name string) (*gcp.Provider, error) {
 	gcpConf := config.New(ctx, "gcp")
-	
+
 	// Get project ID from config
 	projectID := gcpConf.Get("project")
 	if projectID == "" {
 		return nil, fmt.Errorf("GCP project ID not configured. Set gcp:project")
 	}
-	
+
 	// Get region from config or use default
 	region := gcpConf.Get("region")
 	if region == "" {
 		region = "us-central1"
 	}
-	
+
 	// Get credentials from config (base64 encoded service account JSON)
 	credentials := gcpConf.Get("credentials")
 	if credentials != "" {
@@ -45,7 +45,7 @@ func createGCPProvider(ctx *pulumi.Context, name string) (*gcp.Provider, error)
 		}
 		credentials = string(decodedCreds)
 	}
-	
+
 	// Create a GCP provider with explicit credentials if provided
 	if credentials != "" {
 		return gcp.NewProvider(ctx, name, &gcp.ProviderArgs{
@@ -54,7 +54,7 @@ func createGCPProvider(ctx *pulumi.Context, name string) (*gcp.Provider, error)
 			Credentials: pulumi.String(credentials),
 		})
 	}
-	
+
 	return nil, nil
 }
 

docs/reference/server-json/generic-server-json.md

@@ -682,12 +682,11 @@ This example demonstrates URL templating for remote servers, useful for multi-te
   "remotes": [
     {
       "type": "streamable-http",
-      "url": "https://{tenant_host}/api/mcp",
-      "arguments": [
+      "url": "https://api.example.github.io/mcp/{tenant_id}",
+      "variables": [
         {
-          "type": "positional",
-          "valueHint": "tenant_host",
-          "description": "Tenant-specific hostname (e.g., 'us-cell1.example.com')",
+          "name": "tenant_id",
+          "description": "Tenant identifier (e.g., 'us-cell1', 'emea-cell1')",
           "isRequired": true
         }
       ]
@@ -696,7 +695,7 @@ This example demonstrates URL templating for remote servers, useful for multi-te
 }
 ```
 
-Clients would configure the tenant host value, and the `{tenant_host}` variable in the URL gets replaced with the provided argument value to connect to the appropriate deployment (e.g., `us-cell1.example.com` or `emea.example.com`).
+Clients configure the tenant identifier, and the `{tenant_id}` variable in the URL gets replaced with the provided variable value to connect to the appropriate tenant endpoint (e.g., `https://api.example.github.io/mcp/us-cell1` or `https://api.example.github.io/mcp/emea-cell1`).
 
 ### Deprecated Server Example
 

docs/reference/server-json/server.schema.json

@@ -377,7 +377,7 @@
         },
         "url": {
           "type": "string",
-          "description": "URL template for the streamable-http transport. Variables in {curly_braces} reference argument valueHints from 'arguments' array or names from 'environmentVariables' array. If arguments/environmentVariables are not provided, {curly_braces} should be treated as literal text. After variable substitution, this should produce a valid URI.",
+          "description": "URL template for the streamable-http transport. Variables in {curly_braces} reference variable names from the 'variables' array. If variables are not provided, {curly_braces} should be treated as literal text. After variable substitution, this should produce a valid URI.",
           "example": "https://api.example.com/mcp"
         },
         "headers": {
@@ -387,16 +387,9 @@
             "$ref": "#/definitions/KeyValueInput"
           }
         },
-        "arguments": {
+        "variables": {
           "type": "array",
-          "description": "Arguments that can be referenced in URL template {curly_braces} via their valueHint property",
-          "items": {
-            "$ref": "#/definitions/Argument"
-          }
-        },
-        "environmentVariables": {
-          "type": "array",
-          "description": "Environment variables that can be referenced in URL template {curly_braces} via their name property",
+          "description": "Configuration variables that can be referenced in URL template {curly_braces} via their name property",
           "items": {
             "$ref": "#/definitions/KeyValueInput"
           }
@@ -421,7 +414,7 @@
         "url": {
           "type": "string",
           "format": "uri",
-          "description": "Server-Sent Events endpoint URL template. Variables in {curly_braces} reference argument valueHints from 'arguments' array or names from 'environmentVariables' array. If arguments/environmentVariables are not provided, {curly_braces} should be treated as literal text. After variable substitution, this should produce a valid URI.",
+          "description": "Server-Sent Events endpoint URL template. Variables in {curly_braces} reference variable names from the 'variables' array. If variables are not provided, {curly_braces} should be treated as literal text. After variable substitution, this should produce a valid URI.",
           "example": "https://mcp-fs.example.com/sse"
         },
         "headers": {
@@ -431,16 +424,9 @@
             "$ref": "#/definitions/KeyValueInput"
           }
         },
-        "arguments": {
-          "type": "array",
-          "description": "Arguments that can be referenced in URL template {curly_braces} via their valueHint property",
-          "items": {
-            "$ref": "#/definitions/Argument"
-          }
-        },
-        "environmentVariables": {
+        "variables": {
           "type": "array",
-          "description": "Environment variables that can be referenced in URL template {curly_braces} via their name property",
+          "description": "Configuration variables that can be referenced in URL template {curly_braces} via their name property",
           "items": {
             "$ref": "#/definitions/KeyValueInput"
           }

internal/api/handlers/v0/publish.go

@@ -75,14 +75,14 @@ func buildPermissionErrorMessage(attemptedResource string, permissions []auth.Pe
 			permissionStrs = append(permissionStrs, perm.ResourcePattern)
 		}
 	}
-	
+
 	errorMsg := "You do not have permission to publish this server"
 	if len(permissionStrs) > 0 {
 		errorMsg += ". You have permission to publish: " + strings.Join(permissionStrs, ", ")
 	} else {
 		errorMsg += ". You do not have any publish permissions"
 	}
 	errorMsg += ". Attempting to publish: " + attemptedResource
-	
+
 	return errorMsg
 }

internal/api/handlers/v0/publish_integration_test.go

@@ -160,9 +160,9 @@ func TestPublishIntegration(t *testing.T) {
 
 	t.Run("publish fails with invalid token", func(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
-			Name:          "io.github.domdomegg/test-server",
-			Description:   "Test server",
-			Version: "1.0.0",
+			Name:        "io.github.domdomegg/test-server",
+			Description: "Test server",
+			Version:     "1.0.0",
 		}
 
 		body, err := json.Marshal(publishReq)
@@ -183,7 +183,7 @@ func TestPublishIntegration(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
 			Name:        "io.github.other/test-server",
 			Description: "A test server",
-			Version: "1.0.0",
+			Version:     "1.0.0",
 			Repository: model.Repository{
 				URL:    "https://github.com/example/test-server",
 				Source: "github",
@@ -219,8 +219,8 @@ func TestPublishIntegration(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
 			Name:        "io.github.domdomegg/airtable-mcp-server",
 			Description: "A test server with MCPB package",
-			Version: "1.7.2",
-			Status: model.StatusActive,
+			Version:     "1.7.2",
+			Status:      model.StatusActive,
 			Packages: []model.Package{
 				{
 					RegistryType: model.RegistryTypeMCPB,

internal/api/handlers/v0/publish_registry_validation_test.go

@@ -47,7 +47,7 @@ func TestPublishRegistryValidation(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
 			Name:        "com.example/test-server-with-npm",
 			Description: "A test server with invalid npm package reference",
-			Version: "1.0.0",
+			Version:     "1.0.0",
 			Packages: []model.Package{
 				{
 					RegistryType: model.RegistryTypeNPM,
@@ -88,7 +88,7 @@ func TestPublishRegistryValidation(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
 			Name:        "com.example/test-server-mcpb-validation",
 			Description: "A test server with MCPB package and registry validation enabled",
-			Version: "0.0.36",
+			Version:     "0.0.36",
 			Packages: []model.Package{
 				{
 					RegistryType: model.RegistryTypeMCPB,
@@ -138,7 +138,7 @@ func TestPublishRegistryValidation(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
 			Name:        "com.example/test-server-multiple-packages",
 			Description: "A test server with multiple packages where second fails",
-			Version: "1.0.0",
+			Version:     "1.0.0",
 			Packages: []model.Package{
 				{
 					RegistryType: model.RegistryTypeMCPB,
@@ -189,7 +189,7 @@ func TestPublishRegistryValidation(t *testing.T) {
 		publishReq := apiv0.ServerJSON{
 			Name:        "com.example/test-server-first-package-fails",
 			Description: "A test server where first package fails",
-			Version: "1.0.0",
+			Version:     "1.0.0",
 			Packages: []model.Package{
 				{
 					RegistryType: model.RegistryTypeNPM,