Parallels RAS Server

A community-maintained, read-only Model Context Protocol (MCP) server for querying Parallels Remote Application Server (RAS) infrastructure via the RAS REST API.

Gives AI assistants visibility into your RAS environment — infrastructure, site settings, policies, publishing, and sessions — without making any changes.

Not affiliated with Parallels International GmbH. "Parallels" is a trademark of its respective owner.

Scope and intended use

Two transports are supported, selected via the MCP_TRANSPORT environment variable:

• stdio (default) — launched as a local subprocess by the MCP client (Claude Desktop, Claude Code, Cursor, etc.). Intended for an individual administrator on their own workstation, or for development and test environments. Credentials come from the launching process's environment; there is no network listener.
• http — streamable-HTTP listener with a required bearer token. Intended for trusted-network deployments where one server is shared by multiple clients (e.g. behind a reverse proxy that adds TLS). Defaults to binding 127.0.0.1:3000; binding to all interfaces is opt-in.

In either mode this server holds a RAS administrator session and exposes 41 read-only tools. It does not expose write or destructive tools and does not provide multi-tenancy or rate limiting — treat it as an admin-equivalent service and protect access accordingly.

API compatibility: verified against the Parallels RAS v21 REST API. Resources used are stable across v18–v21.

Prerequisites

• Node.js 18 or later
• npm
• Access to a Parallels RAS server with the REST API enabled (port 20443 by default)

Installation

git clone https://github.com/RMITBLOG/ParallelsRAS_MCP.git
cd ParallelsRAS_MCP
npm install
npm run build

Environment Variables

Connection to RAS

Variable	Required	Default	Description
RAS_HOST	Yes	—	RAS server hostname or IP address
RAS_USERNAME	Yes	—	Administrator username
RAS_PASSWORD	Yes	—	Administrator password
RAS_PORT	No	20443	REST API port
RAS_IGNORE_TLS	No	true	Skip TLS certificate verification (for self-signed certs)

Transport

Variable	Required	Default	Description
MCP_TRANSPORT	No	stdio	stdio or http
MCP_HTTP_BEARER_TOKEN	HTTP only	—	Bearer token clients must present in Authorization: Bearer …. Server refuses to start without it. Generate with openssl rand -hex 32.
MCP_HTTP_HOST	No	127.0.0.1	Bind address. Set to 0.0.0.0 to expose on all interfaces (front with TLS termination).
MCP_HTTP_PORT	No	3000	Listen port.

Configuration

The examples below cover the stdio transport, which is the default and what most users want. For the HTTP transport, see Running over HTTP further down.

Claude Desktop

Edit your claude_desktop_config.json (typically at %APPDATA%\Claude\claude_desktop_config.json on Windows or ~/Library/Application Support/Claude/claude_desktop_config.json on macOS):

{
  "mcpServers": {
    "parallels-ras": {
      "command": "node",
      "args": ["/path/to/ParallelsRAS_MCP/build/index.js"],
      "env": {
        "RAS_HOST": "ras-server.example.com",
        "RAS_USERNAME": "administrator",
        "RAS_PASSWORD": "your-password",
        "RAS_PORT": "20443",
        "RAS_IGNORE_TLS": "true"
      }
    }
  }
}

Claude Code

claude mcp add parallels-ras -- node /path/to/ParallelsRAS_MCP/build/index.js

Set environment variables in your shell or in the Claude Code MCP configuration.

Cursor

In Cursor settings, go to Features → MCP Servers and add:

• Name: parallels-ras
• Command: node /path/to/ParallelsRAS_MCP/build/index.js
• Environment: RAS_HOST, RAS_USERNAME, RAS_PASSWORD

Other MCP-compatible clients

For any client supporting MCP over stdio, point it at:

node /path/to/ParallelsRAS_MCP/build/index.js

with the required environment variables set in the client's MCP server configuration.

Running over HTTP

The HTTP transport implements MCP Streamable HTTP and runs as a long-lived process. Use it when you want one server shared by multiple clients on a trusted network — typically behind a reverse proxy that terminates TLS.

Start the server

export RAS_HOST=ras-server.example.com
export RAS_USERNAME=administrator
export RAS_PASSWORD=your-password
export MCP_TRANSPORT=http
export MCP_HTTP_BEARER_TOKEN=$(openssl rand -hex 32)   # required
# export MCP_HTTP_HOST=127.0.0.1                       # default; set 0.0.0.0 to expose
# export MCP_HTTP_PORT=3000

npm run start:http

The server logs the listen address on startup. The MCP endpoint is POST /mcp. Requests must include Authorization: Bearer <MCP_HTTP_BEARER_TOKEN>; missing or wrong tokens return 401.

Connect a client

For clients that support a streamable-HTTP MCP server, point them at http://<host>:<port>/mcp with the bearer token in the Authorization header. For example, the Claude Code CLI:

claude mcp add parallels-ras --transport http \
  --header "Authorization: Bearer $MCP_HTTP_BEARER_TOKEN" \
  http://your-server:3000/mcp

Production checklist

• Always front this with TLS — a reverse proxy (nginx, Caddy, Traefik) terminating HTTPS, with the MCP server bound to 127.0.0.1 and reached only via the proxy.
• Treat MCP_HTTP_BEARER_TOKEN as a credential — at least 32 bytes of entropy, stored in a secret manager, rotated when staff leave.
• Restrict network reachability (firewall, VPN, private subnet). The bearer check is the only auth layer in the server itself.
• The RAS admin credentials sit on the same host as the listener — anyone with shell access on that host can read them. Do not run this on a multi-tenant box.

Available Tools (41 total)

All tools are read-only and annotated with readOnlyHint: true for automatic approval in compatible clients.

List tools (sessions, hosts, certs, agents, published items, etc.) accept three optional inputs for narrowing large responses:

• fields: string[] — keep only these top-level keys on each row.
• filter: Record<string, string|number|boolean> — equality match on top-level fields (AND across keys; strings are case-insensitive).
• limit: number — cap rows after filtering. Default 50, hard max 200.

Responses lead with a one-line NOTE: header summarising total rows, filter matches, and truncation. A 64 KB byte safety net applies to every response.

Infrastructure (14)

Tool	Description
ras_infra_get_agents	List all RAS agents and their status
ras_infra_get_connection_brokers	Connection broker status and priority
ras_infra_get_providers	Cloud/hypervisor providers (AVD, AWS, Azure, Hyper-V, etc.)
ras_infra_get_rds_hosts	RDS session hosts
ras_infra_get_rds_hostpools	RDS host pools
ras_infra_get_certificates	Certificate inventory
ras_infra_get_halb_status	HALB device status
ras_infra_get_enrollment_status	Enrollment server status
ras_infra_get_vdi_hostpools	VDI host pools
ras_infra_get_vdi_templates	VDI templates
ras_infra_get_gateway_status	Secure Client Gateway status
ras_infra_get_sites	Farm sites and their status
ras_infra_get_saml_idps	SAML identity providers for SSO
ras_infra_get_themes	User portal themes and branding

Site Settings (9)

Tool	Description
ras_site_get_ad_integration	Active Directory integration config
ras_site_get_connection_settings	Connection and authentication settings
ras_site_get_load_balancing	Load balancing settings
ras_site_get_mfa	MFA provider configuration
ras_site_get_printing	Printing settings
ras_site_get_tenant_broker	Tenant broker status
ras_site_get_notifications	Notification event configuration
ras_site_get_url_redirection	URL redirection rules
ras_site_get_cpu_optimization	CPU optimization settings

FSLogix is not exposed at site scope by the REST API — it is configured per host pool / per AVD template, or via PowerShell.

Policies (1)

Tool	Description
ras_policies_list	List all client policies

Farm Settings (7)

Tool	Description
ras_farm_get_administrators	Admin accounts and roles
ras_farm_get_config	Farm configuration
ras_farm_get_licensing	Licensing status and seat usage
ras_farm_get_version	Web service version
ras_farm_get_performance	Performance monitor configuration
ras_farm_get_mailbox	SMTP mailbox settings
ras_farm_get_reporting	Reporting configuration

Publishing (9)

Tool	Description
ras_pub_get_rds_apps	Published RDS applications
ras_pub_get_vdi_apps	Published VDI applications
ras_pub_get_avd_apps	Published AVD applications
ras_pub_get_rds_desktops	Published RDS desktops
ras_pub_get_vdi_desktops	Published VDI desktops
ras_pub_get_avd_desktops	Published AVD desktops
ras_pub_get_folders	Resource folders
ras_pub_get_status	Publishing service status
ras_pub_get_all_items	All published items (combined view)

RD Sessions (1)

Tool	Description
ras_sessions_list	Active remote desktop sessions

Extending

Most tools follow one of two shapes: a list tool (the API returns an array of rows) or a single-object tool (config/status blob). Both are registered through factories in src/tools/_format.ts, so adding a new tool is a small ToolDef record plus one factory call.

To add a new tool:

1. Open the appropriate file in src/tools/ (e.g., infrastructure.ts for a new infra resource), or create a new one.

2. Add a ToolDef record to the file's LIST_TOOLS or OBJECT_TOOLS array:

   {
     name: "ras_infra_get_widgets",
     title: "Widgets",
     description: "List widgets in the farm. Supports `fields`, `filter`, `limit`.",
     path: "/api/Widget",
     errorContext: "Failed to retrieve widgets",
   }
   

3. If you created a new file, export a register(server) function that loops over your ToolDef arrays calling registerListTool and/or registerObjectTool, then import and call it from src/index.ts.

4. Run npm run build. The build runs scripts/verify-tool-paths.mjs, which fails the build if the path: you declared isn't a real GET in the v21 OpenAPI spec.

registerListTool automatically wires the fields / filter / limit schema and routes the response through formatList. registerObjectTool skips the schema but still applies the 64 KB byte safety net.

Module file names (infrastructure.ts, site-settings.ts, etc.) are an internal grouping for related tools. They do not correspond to URL segments — the real RAS API is flat under /api/<PascalCaseResource> (e.g. /api/Agent, /api/License, /api/MFA).

API reference

• Browser reference: https://docs.parallels.com/landing/ras-rest-api-guide
• API base URL: https://<ras-host>:20443/api/

Roadmap

• Write operations — out of scope for this repo. A separate server should host any tool that mutates RAS state, so the read-only tools here can stay safe to auto-approve.
• OAuth / OIDC for the HTTP transport — currently a single shared bearer token. Per-user identity would let multiple clients share a deployment without sharing credentials.

Contributing

Issues and pull requests are welcome. Please open an issue first for anything beyond a small fix so we can agree on the approach.

History

See CHANGELOG.md for the full release log. Recent highlights:

• v1.2.0 — efficiency pass across all 41 tools: fields / filter / limit inputs on every list tool, default row cap of 50, 64 KB byte safety net on every response, shared registration factories. Backward-compatible at the MCP protocol level.
• v1.1.0 — opt-in streamable-HTTP transport with bearer-token auth, alongside the existing stdio transport.
• v1.0.1 — corrects all 41 tool paths against the Parallels RAS v21 REST API and adds a build-time path verifier.

License

MIT