Cloudhil

npx add-mcp 'https://cloudhil.com/mcp'

Test your firmware on a real board, from your agent

Compile locally, send the ELF: it runs on a real STM32 or LPC and you get the serial output in under 20 seconds.

4 real boards: Nucleo N6 · Discovery H7 · Nucleo F4 · LPCXpresso55S69

Bench under maintenance

claude mcp add --transport http cloudhil https://cloudhil.com/mcp
# Then: “flash nucleo-f4.elf and read the UART”

How it works

Compile

arm-none-eabi-gcc on your machine. Cloudhil never compiles.

Send the ELF

POST /api/v1/jobs/flash, or ask your agent. One Pay With Prompt voucher: 10 credits = 1 flash.

Read the output

UART, or the NNOK mailbox (0x4E4E4F4B). Under 20 seconds, then erase.

For agents

Remote MCP, recipes, and payment kept separate.

MCP

https://cloudhil.com/mcp

HTTP connector for Claude and other MCP clients. The recipe is in install.md.

install.md AGENTS.md

AGENTS.md

The recipe to paste into the project.

AGENTS.md SKILL.md

SKILL.md

The short move: compile, flash, read.

SKILL.md Pay With Prompt

Payment

10 credits = 1 flash, merchant cloudhil.

paywithprompt.com

Sample ELF

One NNOK hello per board. Success is result.mailbox.ok.

Simulator, bought board, or Cloudhil

A simulator is fast but still a model. A bought board is real but takes time to arrive. Cloudhil gives you a real board in minutes, for a short run.

	Simulator (Renode, Wokwi, QEMU)	Buying the board	Cloudhil
Where the code runs	On a software model of the chip	On your board, at your desk	On a real board, remotely
Time to first run	Minutes	Days or weeks of shipping	Minutes
Peripherals and timing	Whatever the model covers	Real	Real
An AI agent can drive it alone	Yes	No, someone must be at the bench	Yes: HTTP API and MCP connector
Run length	Unlimited	Unlimited	20 seconds at most
Step debugging (GDB, SWD)	Yes	Yes	No: serial output and verdict only
Cost	Free or subscription	Price of board and probe	10 Pay With Prompt credits per flash

FAQ

What is Cloudhil?

Cloudhil is a remote hardware-in-the-loop test bench. You compile your firmware locally, send the ELF or BIN file, it runs on a real STM32 or LPC board, and you read serial output and a pass/fail verdict in under 20 seconds.

Is this a simulator?

No. The firmware runs on the real microcontroller, then the board is erased. Renode, Wokwi and QEMU run code on a software model; Cloudhil runs it on silicon.

When is a simulator the better choice?

For long runs, step debugging, or high-volume continuous integration. Cloudhil is for confirming on real hardware what a simulator cannot guarantee: peripherals, clocks, FPU, DSP or TinyML performance.

Which boards are available?

Four STM32 and LPC evaluation boards, including a NUCLEO-N657X0-Q (Cortex-M55) and a Nucleo-F429ZI (Cortex-M4). The list and the live state of each bench are shown on this page.

Who compiles?

You, or your agent, locally with arm-none-eabi-gcc. Cloudhil does not compile: it only accepts a pre-built ELF or BIN.

How does an AI agent use Cloudhil?

Through the MCP connector at https://cloudhil.com/mcp or the HTTP API (POST /api/v1/jobs/flash). The full recipe is in install.md, AGENTS.md and SKILL.md. No human is needed at the bench.

How long does a run last?

At most 20 seconds, then the board is halted and erased. It is a smoke test, not a long soak.

How much does it cost?

One flash costs 10 Pay With Prompt credits, paid with a one-time voucher. A bench that is down returns 503 and does not spend the voucher.

Is my firmware kept?

No. The board is erased after every run. Do not put secrets in firmware; logs keep only hashed IP addresses and hashed emails.

What is not allowed?

Programming option bytes, RDP, OTP or protected configuration areas; opening a GDB, SWD or SSH session. Such images are rejected with a 400 error.