serial-console-mcp
AI for the configuration of telecommunication equipment, through the console port it already has.
MIT licensed · Python 3.10+ · status: 0.3.2, verified live on a Juniper EX2200 console
serial-console-mcp connects an AI assistant such as Claude to the serial console
of the equipment that runs networks and radio stations, and of anything else
with a serial port:
- Routers and switches. Juniper (Junos) and Cisco (IOS, IOS-XE) console and
craft ports: log in, read state, change configuration with a safety net
(
commit confirmed on Junos, reload in on IOS), and leave the console as it
was found.
- Radio transceivers. Icom and Xiegu over CI-V; Kenwood, Yaesu and Elecraft
over their text CAT protocols: identify the rig, read and set frequency and
mode.
- Antenna rotators. Yaesu GS-232 and the many controllers that speak it:
read the heading, turn, stop.
- Anything else with a serial port. Nothing is tied to telecom: the server
talks raw bytes, cleans up ANSI output, or keeps a full VT100/xterm screen, so
IoT gateways, alarm and access-control panels, UPS and PDU menus, lab
instruments, industrial controllers, Linux and BIOS consoles and
microcontrollers work too.
You say what you want in plain language. The assistant drives the console
through this server, Claude Desktop asks you to approve each step, and bundled
operating skills teach it the Junos and IOS basics: which mode a prompt means,
how to get in and out, which show commands answer everyday questions.
Juniper support is verified on a real EX2200 console. Cisco, CI-V, CAT and
rotator support follows the vendors' protocol references and has not yet met
hardware on this bench. The other device types use the generic tools rather than
device-specific helpers.
You do not need to know any programming. After it's installed you talk to Claude
normally:
You: What serial ports do you see?
Claude: I found two. One looks like a Silicon Labs CP210x on COM4 — that's
probably your device.
You: Connect to COM4 at 9600 baud.
Claude: Connected.
You: Log in and show me the version.
How it works (the important part)
A serial console isn't a simple question-and-answer channel. It echoes what you
type, prints unsolicited messages on its own (logs, interface flaps), and can dump
pages of output. So the moment a port is open, a background reader keeps draining
it into a buffer. That means Claude can:
- send a command (writes only — doesn't guess when the reply is done), then
- read until a prompt appears (
# , > , login: …) to capture the whole
reply — even a long one — without cutting it off, or
- read whatever's waiting for streaming/unsolicited output.
This is the same model minicom and expect use, which is why it handles
interactive CLIs properly.
| Tool | What it does |
|---|
list_serial_ports | Enumerate ports with description and USB hardware id; marks ones open here |
list_presets | Usual settings per device family: Cisco/Juniper/Linux consoles, full-screen consoles (BIOS, BMC, menus), Kenwood/Elecraft/Yaesu CAT, Icom and Xiegu CI-V, rotators, Arduino, NMEA GPS |
connect / reconnect_last / disconnect | Open a port by name. Defaults 9600 8N1, no flow control; baud, data bits, parity, stop bits, RTS/CTS, XON/XOFF, line ending and prompt are all settable, or loaded from a preset. Several ports at once |
send_keys / screen | Press Ctrl-C, Esc, Tab, arrows, F-keys by name; view the VT100/xterm screen of a full-screen console (BIOS, BMC, menu switches, vi) |
send_text / send_hex | Write an ASCII line (CR / LF / CRLF / none) or raw hex bytes. Write-only |
read_until_prompt | Return buffered output up to a literal or regex prompt, leaving the rest; auto_reply pages through --More-- |
read_available | Return whatever has arrived, as text and hex |
query_text | Clear, send, then read until the prompt or until the line goes idle |
expect | A scripted list of send-and-wait steps in one call: logins, command sequences |
set_lines / pulse_line / send_break | Drive DTR and RTS (PTT, Arduino reset), send BREAK |
capture_start / capture_stop / get_transcript | Log a session to a file (raw or timestamped TX/RX); re-read the rolling transcript |
port_in_use_by / detect_baud | Which program holds a port; which baud rate produces readable text |
cat_build / cat_parse | Kenwood, Elecraft and Yaesu ; commands: build a frequency set, decode ID, FA, MD, IF and error replies |
civ_build / civ_parse / civ_freq | Icom CI-V frames: build, decode (echo vs reply, BCD frequency, mode, PTT), convert |
rotator_build / rotator_parse | GS-232 rotator commands (read, move, stop, speed) and position replies |
clear_buffer / status | Housekeeping; status shows every open port with control-line states |
Ports are opened by name ("rig", "rotator"); tools default to the most recently
used one. Each connection has a terminal mode: dumb (raw bytes, the default),
ansi (colours and escape sequences stripped, CR/backspace overwrites applied,
prompts matched on the line as displayed even after a device redraws it with
spaces and backspaces; used by the console presets), or xterm/vt100 (a real screen you can read
with screen; needs pip install 'serial-console-mcp[screen]', included in
the desktop extension). The receive buffer is capped at 4 MB per port; if a device streams for
hours unread, the oldest bytes are dropped and status says how many.
Operating skills
Three skill files in skills/ teach an agent the discipline, the way the
fldigi-mcp skills do; copy them into ~/.claude/skills/ or a project's
.claude/skills/:
| Skill | What it teaches |
|---|
serial-console | The console model, the six rules, terminal modes, keys, presets |
junos-operating | Junos modes from the prompt (% shell, > operational, # configure), out of the BSD shell and back, configure exclusive, show | compare, commit confirmed, rollback, cli -c and start shell, health and interface show commands verified on an EX2200 (show chassis routing-engine, show interfaces terse/brief) |
ios-operating | IOS modes (>, #, (config)#), enable/configure terminal/end, reload in 10 as the safety net, write memory, everyday show commands (show ip interface brief, show processes cpu sorted) |
Environment variables
| Variable | Effect |
|---|
SERIAL_CONSOLE_READ_ONLY=1 | Refuse writes except read-style commands (show, ID;, CI-V reads) and refuse control-line changes |
SERIAL_CONSOLE_ALLOW=<regex> | Override the read-only allowlist |
SERIAL_CONSOLE_IDLE_MINUTES=15 | Auto-close a port idle that long (default: never) |
Set them in the server's entry in claude_desktop_config.json under "env".
Installing
- Download
serial-console-mcp.mcpb from the
Releases page.
The same file works on Mac, Windows and Linux.
- In Claude Desktop, go to Settings → Extensions → Advanced settings →
Install Extension… and choose the file. A short settings form offers
read-only mode and an idle timeout; both are off unless you turn them on.
- In a new chat, type: "What serial ports do you see?" If Claude lists your
ports, you're done.
No terminal, no Python, nothing to configure by hand.
Upgrading from the 0.3.x .pkg or .exe installer? Remove the old copy
first, or Claude Desktop starts two servers. On a Mac:
"/Library/Application Support/SerialConsoleMCP/serial-console-mcp" configure --remove
sudo rm -rf "/Library/Application Support/SerialConsoleMCP"
On Windows, uninstall Serial Console MCP under Settings → Apps. Then quit
and reopen Claude Desktop.
Installing from PyPI
If you already have Python 3.10+ and uv or pipx,
you can skip the extension:
uvx serial-console-mcp --version
uvx serial-console-mcp configure --command uvx --arg serial-console-mcp
or
pipx install serial-console-mcp
serial-console-mcp configure --command "$(which serial-console-mcp)"
configure writes a serial-console entry into claude_desktop_config.json
(merging with whatever is already there and backing the old file up first).
Quit and reopen Claude Desktop. serial-console-mcp configure --remove undoes
it. Any other MCP client can launch the same command over stdio.
Installing from source (developers)
git clone https://github.com/sbrunner-atx/serial-console-mcp.git
cd serial-console-mcp
uv sync
uv run pytest
uv run serial-console-mcp configure --command "$PWD/.venv/bin/serial-console-mcp"
The package lives in src/serial_console_mcp/: server.py is the MCP server,
configure.py the Claude Desktop registrar. manifest.json describes the
desktop extension; npx @anthropic-ai/mcpb pack builds it. BUILD.md
covers the retired .pkg and .exe installers.
Using it
Plain-English requests work. Some examples:
- "List my serial ports."
- "Connect to the console on /dev/cu.usbserial-10 at 9600 baud."
- "Connect to /dev/cu.BLTH at 38400, 8 data bits, no parity, 1 stop bit, XON/XOFF flow control."
- "Connect to the Kenwood with the kenwood-cat preset and call it rig; connect the rotator on the other port."
- "Log in as admin and run show version" (one
expect call: return, login, password, command).
- "What baud rate is this thing?" (
detect_baud).
- "Key the rig for two seconds" (
pulse_line("RTS", 2000), after you confirm).
- "Ask the IC-7300 for its frequency" (
civ_build, send_hex, read_available, civ_parse).
- "What is the TS-590 tuned to?" (
query_text("FA;"), cat_parse).
- "Turn the rotator to 45 degrees and confirm" (
rotator_build, query_text, rotator_parse).
- "Record this console session to a file."
- "Hit Ctrl-C, that ping is still running." (
send_keys)
- "Open the BIOS console at 115200 and show me the screen; go down two and press Enter." (
screen-console preset, screen, send_keys)
- "Reconnect to the same port as last time." (it remembers)
- "Send a return, then read until the login prompt."
- "Log in as admin and run
show interfaces terse, then show me all of it."
- "Just read whatever the device is printing right now."
- "Disconnect when you're done."
For a router/switch console, tell Claude the prompt it should wait for (often #
for enable mode or > for user mode) and it will read until it sees it. For an
Icom radio (CI-V), tell Claude — it can send the hex commands those radios expect.
If something doesn't work
"No serial ports found."
- Is the device turned on?
- Is the USB cable a real data cable, not a charge-only one? (A very common gotcha.)
- On Windows, open Device Manager and look under Ports (COM & LPT). If nothing's
there, Windows needs the cable's driver (often FTDI, CP210x, or CH340).
"Could not open the port" / "access denied."
- A serial port can only be used by one program at a time. Close anything else that
might be holding it: a terminal (PuTTY/minicom/screen), WSJT-X, your contest
logger, the device's own software.
Claude says it can't access serial ports at all.
- Make sure you fully quit and reopened Claude Desktop after installing.
- Start a brand-new chat and ask "What serial ports do you see?" again.
It connected but a command gets no reply.
- Almost always the baud rate is wrong, or the line ending is wrong for your
gear. Most Unix-style consoles want a plain newline (LF); most rigs want a carriage
return (CR). Ask Claude to send a return first to draw a fresh prompt.
A word on safety
These tools send exactly what you (through Claude) ask them to send, to whatever
device is on the cable. Claude Desktop asks you to approve each tool call, so you
see every command before it runs. Read it. A console session on a router or a
rig can reconfigure, reboot, or transmit, and this server does not try to guess
which commands are dangerous. If something looks wrong, decline it, and keep a
real terminal handy for anything you would not want an assistant to type.
License
MIT. See LICENSE.
73!