[FEATURE] Support MCP protocol in ML connector

[ylwu-amzn]

Is your feature request related to a problem?
We support http and aws sigv4 in ML connector now. Can we also support MCP protocol?

What solution would you like?
Add a new protocol "mcp". User can create connector with "mcp".

What alternatives have you considered?
N/A

Do you have any additional context?
Add any other context or screenshots about the feature request here.

[rithin-pullela-aws]

Hi @ylwu-amzn , can you please assign this to me

[ylwu-amzn]

Sure, thanks @rithin-pullela-aws

[ylwu-amzn]

Allow Custom Headers via MCP Client modelcontextprotocol/java-sdk#68

[ylwu-amzn]

Create connector with MCP

POST /_plugins/_ml/connectors/_create
{
    "name": "My MCP Connector",
    "description": "The connector to MCP server",
    "version": 1,
    "protocol": "mcp_sse",
    "credential": {
        "mcp_server_key": "..." # you can change to your own credential, like basic auth, AWS temp credential 
    },
    "url":"<MCP_SERVER_URL>",
    "headers": {
        "Authorization": "Bearer ${credential.mcp_server_key}"
    }
}

Use MCP connector in Agent

You can configure Agent to use tools from MCP server through MCP connector

For example

POST /_plugins/_ml/agents/_register
{
  "name": "My Chat Agent with OpenAI GPT-4",
  "type": "conversational",
  "description": "this is a test agent",
  "llm": {
    "model_id": "OJ2X2ZUBZ_3SyqdODx0W",
    "parameters": {
      "max_iteration": 3,
      "system_instruction": "Assistant is a large language model.\nAssistant is designed to be able to assist with a wide range of tasks.",
      "prompt": "${parameters.question}",
      "disable_trace": true
    }
  },
  "memory": {
    "type": "conversation_index"
  },
  "parameters": {
    "_llm_interface": "openai/v1/chat/completions",
    "mcp_connectors": [ # You can configure multiple MCP connectors each connecting with one MCP server.
        {
            "mcp_connector_id": "NZ2W2ZUBZ_3SyqdOvh2n",
            "tool_filters": [  # filter will be used to choose tools matching these regex
                "get*"
            ]
        },
        {
            "mcp_connector_id": "QZ2c2ZUBZ_3SyqdOXh2H",
            "tool_filters": [
                "get_forecast"
            ]
        }
    ]
  },
  "tools": [
    {
      "type": "ListIndexTool",
      "include_output_in_agent_response": false
    }
  ],
  "app_type": "os_chat"
}