AI MCP Proxy

The AI MCP Proxy plugin lets you connect any Kong-managed Service to the Model Context Protocol (MCP). It acts as a protocol bridge, translating between MCP and HTTP so that MCP-compatible clients can either call existing APIs or interact with upstream MCP servers through Kong.

The plugin’s mode parameter controls whether it proxies MCP requests, converts RESTful APIs into MCP tools, or exposes grouped tools as an MCP server. This flexibility allows you to integrate existing HTTP APIs into MCP workflows, front third-party MCP servers with Kong’s policies, or expose multiple tool sets as a managed MCP server.

Because the plugin runs directly on Kong AI Gateway, MCP endpoints are provisioned dynamically on demand. You don’t need to host or scale them separately, and the Kong AI Gateway applies its authentication, traffic control, and observability features to MCP traffic at the same scale it delivers for traditional APIs.

Note: Unlike other available AI plugins, the AI MCP Proxy plugin is not invoked as part of an LLM request flow. Instead, it’s part of an MCP request flow. It’s registered and executed as a regular plugin, between the MCP client and the MCP server, allowing it to capture MCP traffic independently of LLM request flow.

Do not configure the AI MCP Proxy plugin together with other AI plugins on the same Service or Route.

The AI MCP Proxy bridges the Kong plugin ecosystem with the MCP world, enabling you to bring all of Kong’s traffic management, security, and observability capabilities to MCP endpoints:

The AI MCP Proxy plugin handles MCP requests by converting them into standard HTTP calls and returning the responses in MCP format. The flow works as follows:

1. Accepts MCP protocol requests from a client.
2. Parses the MCP tool call and matches it to an OpenAPI operation.
3. Converts the operation into a standard HTTP request.
4. Sends the request to the upstream Service.
5. Wraps the HTTP response in MCP-compatible format and returns it.

 
sequenceDiagram
    participant C as MCP Client
    participant K as Kong (AI MCP Proxy plugin)
    participant U as Upstream Service

    C->>K: MCP request (tool invocation)
    activate K
    K->>K: Parse MCP payload
    K->>K: Map to HTTP endpoint (OpenAPI schema)
    K->>U: HTTP request
    deactivate K
    activate U
    U-->>K: HTTP response
    deactivate U
    activate K
    K->>K: Convert to MCP format
    K-->>C: MCP response
    deactivate K
  

Pings from your MCP client are included in the total request count for your Kong AI Gateway instance, in addition to the requests made to the MCP server.

Before using the AI MCP Proxy plugin, ensure your setup meets these requirements:

• The upstream Service exposes a valid OpenAPI schema.
• That Service is configured and accessible in Kong.
• An MCP-compatible client (such as Claude, Cursor, or LMstudio) is available to connect to Kong.
• The Kong AI Gateway instance supports the AI MCP Proxy plugin (is 3.12 or higher).

The AI MCP Proxy plugin operates in four modes, controlled by the config.mode parameter. Each mode determines how Kong handles MCP requests and whether it converts RESTful APIs into MCP tools.

The AI MCP Proxy plugin provides support for key MCP operations and upstream interactions, while certain advanced features and non-HTTP protocols are not currently supported. The table below summarizes what is fully supported and what is outside the current scope.