golioth/tinymcp

Let LLMs control embedded devices via the Model Context
Protocol.
> [!WARNING]
> tinymcp is an experimental project. Expect frequent breaking changes.
> Extreme caution should be taken when delegating physical capabilities to AI
> systems.
## Background
The tinymcp project includes an MCP server, which is executed locally, but
communicates with remote devices via the Golioth management
API. It uses two existing
device services on the Golioth platform, LightDB
State and Remote
Procedure Calls (RPCs), to
expose device functionality via MCP.
RPCs can be exposed as
tools
by including a schema in on the mcp/tools/schema path in LightDB State.
Because LightDB State can be updated by devices or users, RPCs on existing
devices can be exposed without needing to modify the device firmware.
## Setup
To use tinymcp, you need to connect a device to the Golioth platform, then run
the tinymcp server on your local machine.
### Firmware
While existing devices can be used without changing the firmware, if you don't
already have a device on Golioth, the blinky example
provides a simple demonstration of how to expose LED control to an LLM via
tinymcp. It uses Zephyr RTOS, which requires
setting up
dependencies
before building. After doing so, you can initialize your workspace with one of
the following commands.
west init -l .
Or, to use the downstream Nordic nRF Connect SDK.
west init -l . --mf west-ncs.yml
With your workspace initialized, use west update to fetch necessary modules
and libraries.
west update --narrow -o=--depth=1
You are now ready to build the firmware and flash your device. See the blinky
documentation for more information.
### Server
In order to run the tinymcp MCP server locally, the following environment
variables need to be supplied.
TINYMCPPROJECT=
TINYMCPDEVICE=
TINYMCPAPIKEY=
The server can be built into an executable using go build -o tinymcp ./server
or run directly with go run ./server.
If you don't already have a device on Golioth, the blinky
example demonstrates how to expose LED control to an LLM via
tinymcp. See the documentation to build and
flash on your device, then expose the registered RPCs in your MCP schema.
There are many MCP client
implementations, most of which should
be compatible with tinymcp. Setup for a few popular options are listed below.
#### MCP Inspector
MCP Inspector is a visual
testing tool for MCP servers. It allows you to interact with MCP methods
directly, rather than going through an LLM. This can be useful when
troubleshooting why an LLM may be failing to interact with your device.
The
documentation
provides information on how to quickly start the inspector. Once it is running,
you can point it to your local tinymcp MCP server by entering