ioBroker.mcp

MCP server for ioBroker

Description

This adapter exposes ioBroker as an MCP (Model Context Protocol) server, so MCP-capable clients (e.g. Claude Desktop) can read and control your installation through a well-defined set of tools.

Related MCP server: MCP REST API Server

Features

• MCP server over the Streamable HTTP transport (/mcp endpoint)

• Configurable HTTP/HTTPS web server

• Configurable port and bind address

• Optional authentication

• Optional SSL/TLS support

• Network diagnostics (ICMP ping / TCP probe) to troubleshoot adapter connections

• Adapter repository search to recommend installable adapters

Operating modes

The adapter can run in two ways:

1. Standalone (default) – it starts its own web server on the configured port. The MCP endpoint is http(s)://<host>:<port>/mcp.

2. Web extension – it runs inside an existing web adapter instance and shares its web server (port, authentication, SSL). Select the target web instance in the admin configuration ("Extend WEB adapter"). The MCP endpoint is then served under the web adapter, e.g. http(s)://<host>:8082/mcp/.

   When a web instance is selected, the standalone server settings (port, bind address, authentication, SSL) are hidden because they are inherited from the chosen web instance.

Configuration

The adapter can be configured through the ioBroker admin interface using JSONConfig:

Server Configuration

• Extend WEB adapter: Select a web instance to run as its extension. Leave empty to run standalone.

• Port: The port on which the web server will listen (default: 8093) – standalone only

• Bind Address: IP address to bind the server to (0.0.0.0 for all interfaces) – standalone only

Authentication

• Enable Authentication: Enable ioBroker user authentication for the web server

• Default User: The ioBroker user whose permissions every MCP request runs with (default: admin). All object/state reads and writes performed by the tools are executed in the name of this user, so the user's ACLs are enforced. A plain name like operator is automatically expanded to system.user.operator. When running as a web extension and no user is set here, the host web instance's default user is used.

OAuth

MCP clients such as Claude Desktop connect through a browser login instead of a token you create by hand. The client discovers the server on its own, the user logs in and confirms, and the client never sees the ioBroker password.

• Enable OAuth (browser login): In standalone mode this requires Enable Authentication. As a web extension the selected web instance provides the login, so OAuth has to be enabled there as well ("Allow third-party clients") — otherwise MCP clients only receive a redirect to the login page, which they cannot use.

• Public URL: The externally reachable address of this server, without a path, e.g. https://iobroker.example.com. Required behind a reverse proxy: the URLs published for OAuth discovery must be the ones the client can actually reach. As a web extension it must match the public URL configured in the web instance.

• Allow client self-registration: Let MCP clients register themselves (default: on). With this off, every client has to be registered by hand first. In web-extension mode this is the web instance's setting, so the option is hidden here.

HTTPS is required for anything but localhost — the flow runs through the user's browser, and MCP clients refuse plain http:// for remote hosts.

Access tokens are bound to this endpoint, so a token issued for another service on the same server is rejected. Clients can drop their tokens again via POST /oauth/revoke.

Permissions

• Allow setting states: Allow MCP clients to write state values (the set_state and set_states tools). Default: on.

• Mark setting states as destructive: Declare set_state and set_states with destructiveHint: true, so MCP clients can warn before a state is written. Default: on. When off, both tools are declared as non-destructive writes (readOnlyHint stays false); whether a client still asks for confirmation then depends on the client.

• Allow object/file changes: Allow MCP clients to create/modify/delete objects and files (the set_object, delete_object, create_state, create_scene, write_file, delete_file, rename_file and mkdir tools). Default: off. When off, these tools are not exposed at all.

SSL/TLS Configuration

• Enable HTTPS: Enable HTTPS/SSL for secure connections

• Public Certificate: Path to the public certificate file

• Private Key: Path to the private key file

• Chained Certificate: Path to the chained certificate file (optional)

Connecting ChatGPT and Claude

There is no official ioBroker app in the connector directories of Claude and ChatGPT yet. Until then, add ioBroker as a custom connector. There are two ways to reach your installation:

A: via ioBroker Remote

1. Configure this adapter (standalone or as web extension). Leave Enable Authentication and Enable OAuth off: the login happens on iobroker.pro, and ioBroker.iot connects to this instance locally without credentials. As a web extension, the selected web instance must not use authentication either. The port does not have to be reachable from the internet.

2. In the settings of ioBroker.iot (logged in with your ioBroker.pro account) enable Allow remote access and select this instance as MCP instance. Save.

3. Add the connector in Claude or ChatGPT (see below) with the URL https://mcp.iobroker.in/mcp.

4. A login page "Connect to ioBroker" opens: enter the e-mail and password of your ioBroker.pro account and click Sign in and allow. Only allow the connection if you have just set it up yourself.

Access is granted with a verified e-mail address and a valid ioBroker.pro license. New accounts can use it for 7 days after the registration without a license.

Good to know:

• ioBroker.iot must be connected to the cloud, otherwise the client gets the error "ioBroker is offline".

• Live updates (subscribing to resources) are not available via Remote. All tools work.

• After a restart of the MCP instance, the client starts a new session by itself.

• Removing the connector in the client ends the access. An already issued access token stays valid for up to one hour. To stop the access immediately, clear MCP instance in ioBroker.iot.

B: directly to your server

1. Enable Enable Authentication and Enable OAuth. As a web extension, enable OAuth ("Allow third-party clients") in the web instance as well.

2. Make the server reachable via HTTPS from the internet and enter this address as Public URL.

3. Use the URL https://<your public address>/mcp (as web extension https://<your public address>/mcp/) in the client and log in with an ioBroker user.

Claude (claude.ai, Claude Desktop)

Custom connectors are available on all plans, the Free plan is limited to one custom connector.

1. Open Customize → Connectors, click + and select Add custom connector.

2. Enter a name (e.g. ioBroker) and the server URL. The Advanced settings (OAuth client ID and secret) stay empty, Claude registers itself.

3. Click Add. If the login does not start by itself, click Connect next to the connector.

4. In a chat, click + (lower left) → Connectors and enable ioBroker.

Team and Enterprise: an owner first adds the connector under Organization settings → Connectors → Add → Custom → Web. Members then open Customize → Connectors and click Connect.

Claude Code:

claude mcp add --transport http iobroker https://mcp.iobroker.in/mcp

Then run /mcp in Claude Code, select iobroker and log in in the browser.

ChatGPT

Custom MCP connections need the developer mode, which is available for Plus, Pro, Business, Enterprise and Education accounts in ChatGPT on the web. In Business and Enterprise workspaces an admin has to allow it first.

1. Open Settings → Security and login and turn on Developer mode.

2. Open ChatGPT Plugins and click +.

3. Enter a name (e.g. ioBroker) and a description (e.g. "Reads and controls my ioBroker smart home"). Under Connection choose Public endpoint and enter the server URL. Choose OAuth as authentication.

4. Create the connection and log in. ChatGPT then lists the tools of ioBroker.

5. In a chat, open + → Developer mode and select ioBroker. It helps to name ioBroker explicitly in the request, e.g. "Use ioBroker to switch off the lights in the kitchen".

ChatGPT marks developer mode connections as elevated risk and asks before write actions.

The menu names are taken from the help pages of Claude and ChatGPT (September 2026) and may change.

Recommendations

• Set a Default User with only the rights the AI should have. Every tool runs with its permissions.

• Leave Allow object/file changes off unless you need it.

• Leave Mark setting states as destructive on, so the clients ask before they switch something.

MCP Endpoint

The MCP server is served at POST/GET/DELETE /mcp using the Streamable HTTP transport with per-session state (tracked via the Mcp-Session-Id header). Point your MCP client at:

• standalone: http(s)://<host>:<port>/mcp

• web extension: http(s)://<host>:<webPort>/mcp/

Available tools

All object/state access runs with the permissions of the configured Default User. The write tools are only registered when their respective permission option is enabled.

Resources & live updates (SSE)

States and objects are also exposed as MCP resources using the canonical ioBroker URI scheme, so clients can read and subscribe to them. The server pushes changes over the Streamable HTTP SSE stream (notifications/resources/updated).

• States: iobstate://<id> (e.g. iobstate://javascript.0.temperature) – resources/read returns { id, val, ack, ts, lc, q }.

• Objects: iobobject://<id> (e.g. iobobject://system.adapter.admin.0) – resources/read returns the object.

• Logs: ioblog://all (every source) or ioblog://<source> (e.g. ioblog://admin.0) – resources/read returns the recent log lines ({ source, logs: [{ ts, level, source, message }] }). Subscribing enables log forwarding for the adapter; each new matching line triggers a notifications/resources/updated.

• resources/subscribe subscribes to the underlying ioBroker state/object/log; on every change the client receives a notifications/resources/updated for that URI and re-reads it. resources/unsubscribe stops it.

Subscriptions are tracked per session and ref-counted, so the adapter subscribes to a state/object only once regardless of how many clients/sessions watch it, and unsubscribes when the last one leaves.

(Files use iobfile://<adapter>/<path> in the same scheme; they are available via the read_file/write_file tools rather than as subscribable resources.)

Health endpoints (non-MCP)

• GET / - Basic server information

• GET /status - Server status, uptime and active session count

• GET /api/info - Adapter information

Changelog

1.1.7 (2026-09-15)

• (@GermanBluefox) Added instructions for connecting ChatGPT and Claude (via ioBroker Remote or directly)

• (@GermanBluefox) Added IP address selector

• (@GermanBluefox) New option "Mark setting states as destructive" (default on): set_state/set_states can be declared as non-destructive writes

1.1.4 (2026-09-03)

• (@GermanBluefox) read_file reads large files in chunks: new optional offset/length parameters, at most 512 KiB per call by default; the result now contains size, offset, length, truncated and nextOffset (MCP clients reject tool results above 1 MB, ioBroker/ioBroker.mcp#63)

1.1.3 (2026-09-03)

• (ioBroker-Bot) Adapter requires admin >= 7.8.23 now.

• (@GermanBluefox) Updated packages

1.1.2 (2026-08-26)

• (@GermanBluefox) Node.js 22 is required now

• (@GermanBluefox) Corrected OAuth page

1.1.0 (2026-08-04)

• (@GermanBluefox) Added OAuth: MCP clients can now be connected through a browser login instead of a manually created token

• (@GermanBluefox) OAuth also works as a web extension, using the host web instance as the authorization server (requires OAuth enabled there too)

• (@GermanBluefox) Updated @iobroker/mcp-server and @iobroker/webserver

Older changelogs can be found there

License

MIT License

Copyright (c) 2025-2026 ioBroker

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.