Implementation:BerriAI Litellm MCP Registry

Overview

Description

The litellm/proxy/mcp_registry.json file is a curated catalog of well-known MCP (Model Context Protocol) servers that can be added to a LiteLLM Proxy deployment. The registry powers the MCP Server Discovery UI in the proxy dashboard, providing a browsable grid of pre-configured server options across categories like Developer Tools, Databases, Communication, Productivity, Cloud, and more.

Each server entry includes connection details (transport type, URL or command), required environment variables, and display metadata (icons, descriptions, categories). The registry supports three transport types: HTTP (streamable HTTP), SSE (Server-Sent Events), and stdio (command-line process).

Usage

The file is loaded by the _load_mcp_registry() function in litellm/proxy/management_endpoints/mcp_management_endpoints.py. It is cached in memory after first read and served via the GET /mcp/discover endpoint. Only proxy administrators can access this endpoint.

# Loading path:
_MCP_REGISTRY_PATH = os.path.join(
    os.path.dirname(os.path.dirname(os.path.abspath(__file__))),
    "mcp_registry.json",
)
# Cached after first load
_mcp_registry_cache: Optional[Dict[str, Any]] = None

Data Schema

Top-Level Structure

{
    "servers": [
        {
            "name": "github",
            "title": "GitHub",
            "description": "Manage repos, issues, PRs, and workflows...",
            "icon_url": "https://cdn.simpleicons.org/github",
            "category": "Developer Tools",
            "registry_url": "https://registry.modelcontextprotocol.io/servers/...",
            "transport": "http",
            "url": "https://api.githubcopilot.com/mcp/",
            "env_vars": [
                {"name": "GITHUB_PERSONAL_ACCESS_TOKEN", "description": "...", "secret": true}
            ]
        },
        ...
    ]
}

Schema Fields

Server Entry Object

Field	Type	Required	Description
name	String	Yes	Unique slug identifier (e.g., "github", "postgresql", "slack")
title	String	Yes	Human-readable display name (e.g., "GitHub", "PostgreSQL")
description	String	Yes	Brief description of the server's capabilities
icon_url	String	Yes	URL to the server's icon image (typically from cdn.simpleicons.org)
category	String	Yes	Category for UI grouping and filtering
registry_url	String/null	Yes	URL to the official MCP registry entry, or null if not registered
transport	String	Yes	Connection type: "http", "sse", or "stdio"
url	String	Conditional	Server endpoint URL (required for http and sse transports)
command	String	Conditional	Command to run (required for stdio transport, e.g., "npx", "uvx")
args	Array[String]	Conditional	Command arguments (required for stdio transport)
env_vars	Array[Object]	Yes	Required environment variables for the server

Environment Variable Object

Field	Type	Description
name	String	Environment variable name (e.g., "GITHUB_PERSONAL_ACCESS_TOKEN")
description	String	Human-readable description of what the variable is for
secret	Boolean	Whether the value should be treated as a secret (masked in UI)

Transport Types

Transport	Connection Fields	Description
http	url	Streamable HTTP connection to a remote MCP server
sse	url	Server-Sent Events connection to a remote MCP server
stdio	command, args	Local process spawned via command execution

Categories

The registry organizes servers into the following categories:

Category	Example Servers
Developer Tools	GitHub, GitLab, Atlassian (Jira & Confluence), Linear, Sentry
Communication	Slack, Discord, Twilio
Databases	PostgreSQL, SQLite, MySQL, MongoDB, Redis, Snowflake, Supabase
Productivity	Notion, Google Drive
Web & Browser	Playwright, Browserbase
Cloud	AWS, Cloudflare
System	Filesystem, Docker
Finance	Stripe
E-Commerce	Shopify

Registered Servers

The registry contains entries for the following servers (non-exhaustive):

Server	Transport	Notable Env Vars
GitHub	http	GITHUB_PERSONAL_ACCESS_TOKEN
GitLab	http	GITLAB_PERSONAL_ACCESS_TOKEN
Atlassian	sse	(none -- uses OAuth)
Linear	sse	(none -- uses OAuth)
Sentry	stdio	SENTRY_ACCESS_TOKEN
Slack	stdio	SLACK_BOT_TOKEN, SLACK_TEAM_ID
Discord	stdio	DISCORD_BOT_TOKEN
PostgreSQL	stdio	POSTGRES_CONNECTION_STRING
SQLite	stdio	SQLITE_DB_PATH
MySQL	stdio	MYSQL_HOST, MYSQL_USER, MYSQL_PASSWORD, MYSQL_DATABASE
MongoDB	stdio	MONGODB_CONNECTION_STRING
Redis	stdio	REDIS_URL
Snowflake	stdio	SNOWFLAKE_ACCOUNT, SNOWFLAKE_USER, SNOWFLAKE_PASSWORD
Notion	sse	(none -- uses OAuth)
Stripe	http	(none -- uses OAuth)
AWS	stdio	AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION
Cloudflare	sse	(none -- uses OAuth)

Usage Examples

How the Discovery Endpoint Works

# From litellm/proxy/management_endpoints/mcp_management_endpoints.py:

@router.get("/discover",
    description="Returns a curated list of well-known MCP servers for discovery UI")
async def discover_mcp_servers(
    query: Optional[str] = Query(None, description="Search filter"),
    category: Optional[str] = Query(None, description="Filter by category"),
    ...
):
    """Used by the UI to show a discovery grid when adding new MCP servers."""
    registry = _load_mcp_registry()
    servers = registry.get("servers", [])

    # Apply query filter (searches name, title, description)
    if query:
        query_lower = query.lower()
        servers = [
            s for s in servers
            if query_lower in s.get("name", "").lower()
            or query_lower in s.get("title", "").lower()
            or query_lower in s.get("description", "").lower()
        ]

    # Apply category filter
    if category:
        servers = [s for s in servers if s.get("category", "") == category]

    # Extract unique categories for filter sidebar
    categories = sorted(set(s.get("category", "") for s in all_servers))

    return {"servers": servers, "categories": categories, ...}

How MCP Registry Data is Used for Semantic Filtering

The registry is also used by the semantic tool filter to build a router for MCP tool discovery:

# From litellm/proxy/_experimental/mcp_server/semantic_tool_filter.py:
async def build_router_from_mcp_registry(self) -> None:
    """Build a semantic router from the MCP registry server entries."""
    ...

Related Pages

• Provider Endpoints Support - Provider capability matrix for LLM endpoints
• Callback Configs - Callback integration configuration