CohostSTR (MCP server for Guesty)

CohostSTR — MCP server for Guesty

An open-source, write-capable MCP (Model Context Protocol) server for Guesty property management. Connect any MCP-compatible AI client (Claude, ChatGPT, Copilot, Cline) to your Guesty account — manage reservations, communicate with guests, track finances, update pricing.

Live now: all 43 Guesty tools, free — reservations, listings, guests, calendars, guest messaging, financial reports, pricing and listing writes, operations, reviews, webhooks, and IoT/property-health. No license key, no paid tier.

Why MCP: Guesty is one of the larger PMS platforms in the short-term-rental space and no MCP integration existed. Every major PMS will need one.

Built and run in production on our own short-term rental portfolio. Node.js + MCP SDK + Express, MIT licensed. Things we learned: Guesty's /reservations endpoint only returns future data (we use the calendar endpoint for historical), and the SSE transport doesn't run on Vercel serverless (expected). All 44 tools free.

Full tool surface: 44 tools registered, all free — 43 Guesty tools (23 read-only, 16 write/guest-messaging including get_conversations and draft_guest_reply, and 4 IoT/property-health) plus get_license_info, which reports this server's own licensing state and makes no Guesty API call. There are no paid tiers. GUESTY_MCP_LICENSE_KEY is optional and does not change what you can call.

Everything is free. All 44 tools work with no license key. Paid-prefix keys are still recognized (they show up in get_license_info) but are not required and unlock nothing extra — there is nothing extra to unlock. Set or omit GUESTY_MCP_LICENSE_KEY; access is the same either way.

Quick Start

Easiest: one command for Claude Desktop (your key is never shown on screen)

npx -y cohoststr-mcp setup

It asks for your Guesty Client ID and Client Secret in a hidden prompt (nothing is echoed, not even asterisks), backs up your existing Claude Desktop config, adds CohostSTR, and keeps any other MCP servers you already have. Then quit and reopen Claude Desktop. When Claude asks to use a tool that changes something, allow it one time only (not "always"), so you approve each change.

Or configure it yourself

npx cohoststr-mcp

Claude Code:

claude mcp add cohoststr -s user -e GUESTY_CLIENT_ID=your-client-id -e GUESTY_CLIENT_SECRET=your-client-secret -- npx -y cohoststr-mcp

Claude Desktop by hand: Settings > Developer > Edit Config, then add under mcpServers:

{

"mcpServers": { "cohoststr": { "command": "npx", "args": ["-y", "cohoststr-mcp"], "env": { "GUESTY_CLIENT_ID": "your-client-id", "GUESTY_CLIENT_SECRET": "your-client-secret" } } } }

Get Guesty API Credentials

Requires a Guesty plan with Open API access (Pro or Enterprise; not Lite, per guesty.com/pricing).

1. Log into Guesty
2. Go to Integrations > Developer tools > OAuth applications and create a new API application (Guesty quick-start guide)
3. Copy your Client ID and Client Secret (Guesty shows the secret only once)

All 44 Tools

Reservations & Guests

Listings & Calendar

Messaging

Financials & Pricing

Operations

Automation & Integrations

Server & Licensing

It is counted in the 44 registered tools but not in the "43 Guesty tools" figure, because it reports our licensing state rather than doing anything with your Guesty account: 43 Guesty tools + this one = 44.

IoT & Property Health

These four tools are free like everything else. They read the local IoT database (IOT_DB_PATH) that the optional webhook receiver (src/webhook/iot-receiver-server.js) populates. With no devices reporting they return empty device and alert lists, a low readiness score that names each missing signal, and null IoT fields in the health snapshot — not errors — and the Guesty-side fields still fill in.

Use Cases

• Guest Communication: guest-messaging tools draft and send replies grounded in real reservation data
• Revenue Management: Pull financial reports, analyze occupancy, optimize pricing
• Operations: Track check-ins/outs, coordinate cleaning schedules, manage availability
• Marketing: Identify low-occupancy periods, create targeted promotions
• Connected Tools: give every MCP-compatible client in your stack access to the same property data

Requirements

• Node.js 18+
• Guesty account with API access (Professional plan or higher)
• MCP-compatible AI client (Claude Code, Cursor, Windsurf, etc.)

Environment Variables

API Reference

This server wraps the Guesty Open API. Authentication uses OAuth2 client credentials flow with automatic token caching, retry logic, and rate limit handling.

Built By

Built and run by a short-term rental operator on its own portfolio, shared with the STR community. Not affiliated with Guesty.

License

MIT