Change fields related to server json struct to follow camelCase instead of snake_case (#488)

## Motivation and Context
Aligns with issue
#428
To bring consistency across naming convention

## How Has This Been Tested?
- Locally test cases are tested

## Breaking Changes
- Yes, they have to update the server fields
- 
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update

## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [x] I have added or updated documentation as needed

---------

Co-authored-by: tadasant <[email protected]>

Author: pree-dew

cmd/publisher/commands/init.go

@@ -301,7 +301,7 @@ func createServerJSON(
 
 	// Create server structure
 	return apiv0.ServerJSON{
-		Schema:      "https://static.modelcontextprotocol.io/schemas/2025-07-09/server.schema.json",
+		Schema:      "https://static.modelcontextprotocol.io/schemas/2025-09-16/server.schema.json",
 		Name:        name,
 		Description: description,
 		Status:      model.StatusActive,

cmd/publisher/commands/publish.go

@@ -37,6 +37,17 @@ func PublishCommand(args []string) error {
 		return fmt.Errorf("invalid server.json: %w", err)
 	}
 
+	// Check for deprecated schema and recommend migration
+	// Allow empty schema (will use default) but reject old schemas
+	if serverJSON.Schema != "" && !strings.Contains(serverJSON.Schema, "2025-09-16") {
+		return fmt.Errorf(`deprecated schema detected :%s.
+
+Migrate to the current schema format for new servers.
+
+📋 Migration checklist: https://github.com/modelcontextprotocol/registry/blob/main/docs/reference/server-json/CHANGELOG.md#migration-checklist-for-publishers
+📖 Full changelog with examples: https://github.com/modelcontextprotocol/registry/blob/main/docs/reference/server-json/CHANGELOG.md`, serverJSON.Schema)
+	}
+
 	// Load saved token
 	homeDir, err := os.UserHomeDir()
 	if err != nil {

cmd/publisher/commands/publish_test.go

@@ -0,0 +1,133 @@
+package commands
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	apiv0 "github.com/modelcontextprotocol/registry/pkg/api/v0"
+	"github.com/modelcontextprotocol/registry/pkg/model"
+)
+
+func TestPublishCommand_DeprecatedSchema(t *testing.T) {
+	// Create a temporary directory for test files
+	tempDir, err := os.MkdirTemp("", "mcp-publisher-test")
+	if err != nil {
+		t.Fatalf("Failed to create temp dir: %v", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	// Change to temp directory
+	originalDir, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("Failed to get current dir: %v", err)
+	}
+	defer os.Chdir(originalDir)
+
+	if err := os.Chdir(tempDir); err != nil {
+		t.Fatalf("Failed to change to temp dir: %v", err)
+	}
+
+	tests := []struct {
+		name        string
+		schema      string
+		expectError bool
+		errorSubstr string
+	}{
+		{
+			name:        "deprecated 2025-07-09 schema should show warning",
+			schema:      "https://static.modelcontextprotocol.io/schemas/2025-07-09/server.schema.json",
+			expectError: true,
+			errorSubstr: "deprecated schema detected",
+		},
+		{
+			name:        "current 2025-09-16 schema should pass validation",
+			schema:      "https://static.modelcontextprotocol.io/schemas/2025-09-16/server.schema.json",
+			expectError: false,
+		},
+		{
+			name:        "empty schema should pass validation",
+			schema:      "",
+			expectError: false,
+		},
+		{
+			name:        "custom schema without 2025-07-09 should pass validation",
+			schema:      "https://example.com/custom.schema.json",
+			expectError: true,
+			errorSubstr: "deprecated schema detected",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Create test server.json with specific schema
+			serverJSON := apiv0.ServerJSON{
+				Schema:      tt.schema,
+				Name:        "com.example/test-server",
+				Description: "A test server",
+				Version:     "1.0.0",
+				Status:      model.StatusActive,
+				Repository: model.Repository{
+					URL:    "https://github.com/example/test",
+					Source: "github",
+				},
+				Packages: []model.Package{
+					{
+						RegistryType:    model.RegistryTypeNPM,
+						RegistryBaseURL: model.RegistryURLNPM,
+						Identifier:      "@example/test-server",
+						Version:         "1.0.0",
+						Transport: model.Transport{
+							Type: model.TransportTypeStdio,
+						},
+					},
+				},
+			}
+
+			jsonData, err := json.MarshalIndent(serverJSON, "", "  ")
+			if err != nil {
+				t.Fatalf("Failed to marshal test JSON: %v", err)
+			}
+
+			// Write server.json to temp directory
+			serverFile := filepath.Join(tempDir, "server.json")
+			if err := os.WriteFile(serverFile, jsonData, 0o600); err != nil {
+				t.Fatalf("Failed to write server.json: %v", err)
+			}
+
+			err = PublishCommand([]string{})
+
+			if tt.expectError {
+				if err == nil {
+					t.Errorf("Expected error for deprecated schema, but got none")
+					return
+				}
+				if !strings.Contains(err.Error(), tt.errorSubstr) {
+					t.Errorf("Expected error containing '%s', got: %v", tt.errorSubstr, err)
+				}
+				// Check that the error contains the migration links
+				if !strings.Contains(err.Error(), "Migration checklist:") {
+					t.Errorf("Expected error to contain migration checklist link")
+				}
+				if !strings.Contains(err.Error(), "Full changelog with examples:") {
+					t.Errorf("Expected error to contain changelog link")
+				}
+			} else {
+				// For non-deprecated schemas, we expect the command to fail at auth step, not schema validation
+				if err != nil && strings.Contains(err.Error(), "deprecated schema detected") {
+					t.Errorf("Unexpected deprecated schema error for schema '%s': %v", tt.schema, err)
+				}
+
+				// We expect auth errors for valid schemas since we don't have a token
+				if err != nil && !strings.Contains(err.Error(), "not authenticated") && !strings.Contains(err.Error(), "failed to read token") {
+					t.Logf("Expected auth error for valid schema, got: %v", err)
+				}
+			}
+
+			// Clean up for next test
+			os.Remove(serverFile)
+		})
+	}
+}