# For Developers

**Server URL:** `https://apps.gomarble.ai/mcp-api/sse`  
**Authentication:** OAuth 2.0 with account authorization required  
**Protocol:** SSE-based (Server-Sent Events) - not Streamable HTTP

#### Sample Implementation

Here's a complete example using the FastMCP client library to connect to the Marble MCP server:

```python
import asyncio
import logging
from pathlib import Path
from fastmcp import Client
from fastmcp.client.auth import OAuth

# Set up logging to see what's happening
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

async def main():
    # Configure OAuth with the MCP server URL
    oauth = OAuth(
        mcp_url="https://apps.gomarble.ai/mcp-api/sse",
        scopes=["read", "write"],  # Adjust scopes as needed
        client_name="FastMCP OAuth Client",
        token_storage_cache_dir=Path.home() / ".fastmcp" / "oauth-mcp-client-cache"
    )

try:
        # Create client with OAuth authentication
        async with Client("https://apps.gomarble.ai/mcp-api/sse", auth=oauth) as client:
            logger.info("OAuth client connected successfully")
            # Test the connection
            await client.ping()
            logger.info("Server ping successful")
            # List available tools
            tools = await client.list_tools()
            logger.info(f"Available tools: {len(tools.tools)}")
            for tool in tools.tools:
                logger.info(f" - {tool.name}: {tool.description}")
            # List available resources
            resources = await client.list_resources()
            logger.info(f"Available resources: {len(resources.resources)}")
            for resource in resources.resources:
                logger.info(f" - {resource.uri}: {resource.name}")
            # List available prompts
            prompts = await client.list_prompts()
            logger.info(f"Available prompts: {len(prompts.prompts)}")
            for prompt in prompts.prompts:
                logger.info(f" - {prompt.name}: {prompt.description}")
    except Exception as e:
        logger.error(f"Error connecting to MCP server: {e}")
        raise

if __name__ == "__main__":
    asyncio.run(main())
```

For more details on FastMCP OAuth implementation, see: [FastMCP OAuth](https://gofastmcp.com/clients/auth/oauth)

#### Client Implementation Requirements

##### Technical Prerequisites

- **SSE Support:** Your MCP client must support Server-Sent Events (SSE) based servers  
- **OAuth 2.0 Flow:** Implement OAuth authentication handling  
- **HTTPS:** All communications must use encrypted HTTPS connections  
- **Rate Limiting:** Implement client-side rate limiting (25 requests per minute per user)

##### Authentication Implementation

The server uses OAuth 2.0 for secure authentication. Your client must:

1. Handle OAuth authentication flows
2. Manage access tokens with limited lifetime and scope
3. Implement token refresh mechanisms
4. Handle authentication errors gracefully

##### Connection Configuration

```json
{
    "server_url": "https://apps.gomarble.ai/mcp-api/sse",
    "authentication": "oauth2",
    "protocol": "sse"
}
```

#### Development Best Practices

##### Error Handling

- **Authentication Errors:** Implement graceful handling for auth failures
- **API Calls:** Use proper error handling for all API interactions
- **Connection Issues:** Handle network connectivity problems
- **Rate Limiting:** Implement exponential backoff for rate limit hits

##### Performance Optimization

- **Caching:** Cache responses when appropriate to improve performance
- **Rate Limiting:** Use client-side rate limiting to prevent API abuse
- **Connection Management:** Maintain stable SSE connections

#### Debugging and Troubleshooting

##### Common Development Issues

##### Connection Issues

**Symptoms:**

- Failed SSE connections  
- Timeout errors  
- Protocol mismatches

**Solutions:**

1. Verify SSE protocol support in your client
2. Check network connectivity to `https://apps.gomarble.ai/mcp-api/sse`
3. Ensure HTTPS handling is correct
4. Validate connection parameters

##### Rate Limiting Issues

**Symptoms:**

- HTTP 429 responses  
- Request throttling  
- Performance degradation

**Solutions:**

1. Implement proper rate limiting (25 requests/minute)
2. Add exponential backoff
3. Cache responses to reduce API calls
4. Monitor request frequency

#### Security Considerations for Developers

##### Implementation Requirements

- **OAuth 2.0:** Proper implementation of OAuth authentication flow
- **HTTPS Only:** All communications must use encrypted connections
- **Token Management:** Secure storage and handling of access tokens
- **Scope Validation:** Respect user permission boundaries

#### Support Resources

##### Developer Support

When seeking technical support, provide:

- **Client Implementation Details:** Programming language, framework, version
- **Error Messages:** Complete error logs and stack traces
- **Connection Configuration:** Your client's MCP server configuration
- **Reproduction Steps:** Detailed steps to reproduce the issue
- **Expected vs Actual Behavior:** Clear description of the problem

##### Technical Support Channels

- **Email Support:** Contact technical support with implementation questions at admin@gomarble.ai
- **Documentation:** Reference this [guide](/content/docs/mcp-server-overview/index.html) for implementation details.