MCP Configuration Guide

Overview

In Javelin, MCP registries define how your gateway connects to external Model Context Protocol (MCP) servers and exposes their tools to applications.
Each registry includes connection details, authentication credentials, and baseline policy controls. You can also selectively enable tools on a per-registry basis to safely extend application capabilities.

MCP Registry Payload Example

mcp_registry:
  name: "deepwiki"                                # Unique server key
  description: "Deepwiki MCP server"              # Optional description
  type: "streamable-http"                         # MCP server transport/type
  endpoint: "https://mcp.deepwiki.com/mcp"        # MCP server endpoint URL
  is_active: true                                 # Enable/disable the registry
  config:
    authorization_token: "<SECRET_TOKEN>"         # Optional. Token used by MCP server, if needed
  policy:
    dlp:
      enabled: false
      strategy: ""
    prompt_safety:
      enabled: false
      content_types: []
      reject_prompt: ""

Field Descriptions

Name	Type	Required	Default	Description
name	string	Yes	—	Unique key for this MCP server (e.g., deepwiki).
description	string	No	—	Human-readable description.
type	string	Yes	—	MCP server type/transport (e.g., streamable-http).
endpoint	string	Yes	—	Base URL for the MCP server.
is_active	boolean	No	true	Whether the MCP registry is enabled.
config.authorization_token	string	No	—	Optional. Credential used to authenticate with the MCP server, if needed.

Policy Fields

Name	Type	Required	Default	Description
dlp	object	No	—	Detects and prevents the exposure of sensitive information such as personally identifiable data, credentials, or confidential terms in model interactions.
prompt_safety	object	No	—	Protects against manipulation attempts like prompt injections or jailbreaks that try to bypass model restrictions or redirect behavior.

Tool Enable/Disable Payload

Use this payload to enable or disable a specific tool for an MCP server.

tool:
  enabled: true

Name	Type	Required	Description
enabled	boolean	Yes	Whether the tool is enabled for this MCP server.

Policy Precedence

• If a request uses a gateway key (X-Javelin-Apikey), the MCP registry policy is applied.
• If a request uses an application key (X-Javelin-Apikey), the application policy is applied.