J-Link MCP

Give AI hands to touch silicon. An MCP server that lets LLMs debug embedded devices through SEGGER J-Link probes. Its 40 documented tools cover gdb, rtt, server, telnet. It runs locally over stdio via the published package.

People who work with gdb, rtt and server and want it reachable from Claude, Cursor, VS Code, or another MCP client. The project is written in TypeScript.

VERIFIED ACTIVE

LAST COMMIT 2026-09-15 · ★ 30 · #44 OF 168 MAINTAINED DEVELOPER TOOLS · VERIFIED 2026-09-18

MIT · TypeScript servers · how we verify → /methodology

01 · Install J-Link MCP

before you install - you'll need

Set PROBE_TYPE, OPENOCD_INTERFACE, OPENOCD_TARGET, BMP_SERIAL_PORT before connecting.

Claude Code

claude mcp add klievan-jlink-mcp -- npx -y jlink-mcp

Claude Desktop / Cursor / VS Code - add to config

{
  "mcpServers": {
    "klievan-jlink-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "jlink-mcp"
      ]
    }
  }
}

Same JSON for Cursor. For VS Code, rename the top-level key from `mcpServers` to `servers`.

Using another client? Same JSON, different key

Claude Desktop · mcpServers

Cursor · mcpServers

VS Code · servers

Windsurf · mcpServers

Zed · context_servers

Cline · mcpServers

Roo Code · mcpServers

Continue · mcpServers

LibreChat · mcpServers

Gemini CLI · mcpServers

Codex CLI · mcp_servers

Full setup guides: every client.

02 · Evidence

Security posture

What to check before giving this server access to your agent - from the registry, GitHub, and our own probes. We don't score safety; we show what's verifiable.

runs as local process (stdio) - runs on your machine with your user's permissions

license MIT - declared in the repository

npm package jlink-mcp - unscoped; check the name against the project README before installing

registry namespace io.github.Klievan is GitHub-verified and matches the repo owner

03 · What J-Link MCP can do

Prose above is summarized from the project's README and registry record - no invented capabilities.

What you can build

With this server connected, an agent can capture full device state: registers, fault status, stack dump, RTT output, scan for connected probes and show the configured target, read a peripheral's registers and decode each one's bit fields by name, and read memory at address (clean hex dump output).

Capability map

Tools grouped from the project's README - what J-Link MCP lets an agent do.

Gdb

9 tools - e.g. Start probe's GDB server; Stop GDB server + disconnect RTT; GDB server, RTT, and proxy status

gdb_server_start · gdb_server_stop · gdb_server_status · gdb_connect · gdb_load · gdb_backtrace…

read & search

6 tools - e.g. Scan for connected probes and show the configured target; Current probe, target device, and GDB server state; Every peripheral and base address on the chip

list_devices · get_config · list_peripherals · read_peripheral · read_registers · read_register

Rtt

6 tools - e.g. Connect to RTT telnet port; Disconnect from RTT; Read recent log lines (ANSI stripped, Zephyr format parsed)

rtt_connect · rtt_disconnect · rtt_read · rtt_search · rtt_send · rtt_clear

Telnet

3 tools - e.g. Start TCP proxy that tees RTT for external detokenizers; Stop proxy; Proxy connection status

telnet_proxy_start · telnet_proxy_stop · telnet_proxy_status

Device

2 tools - e.g. Change the target device at runtime - no restart needed; Probe type, target CPU, compact register summary

set_device · device_info

Memory

2 tools - e.g. Read memory at address (clean hex dump output); Write 32-bit value to address

read_memory · write_memory

run & execute

1 tool - e.g. One-call setup. Starts GDB server + connects RTT + returns boot log.

start_debug_session

Snapshot

1 tool - e.g. Captures full device state: registers, fault status, stack dump, RTT output.

snapshot

Latest releases

v0.7.0 · 2026-08-28

Everything three rounds of pointing a fresh agent at real hardware turned up. Most of it was tools stating things they had not checked. · Added · rtt_status - reads SEGGER's control block and reports what the target…

v0.6.0 · 2026-08-28

Aimed at what people reported from using this at work: assistants never loaded the ELF, guessed part numbers, reasoned about hardware instead of asking it, and left GDB servers holding the probe. · Added · An…

v0.5.1 · 2026-08-26

Marketplace metadata only - no code changes, and nothing to gain by upgrading if you already have 0.5.0. · 0.5.0 was published from a build made before the listing was updated, so it went out with the old name and…

04 · Who maintains J-Link MCP

J-Link MCP is maintained by klievan. It's the only MCP server we track from this author; the repo dates to Apr 2026.

05 · Facts

category
developer tools - ranked #44 of 168 actively-maintained developer tools servers as of 2026-09-18.
release cadence
5 releases in the last 90 days (latest 2026-08-28)
registry
io.github.Klievan/jlink-mcp (active, first published 2026-08-28)
packages
npm:jlink-mcp

06 · J-Link MCP FAQ

Is J-Link MCP still maintained?

Yes - as of 2026-09-18, its last commit was 2026-09-15 and it shipped 5 releases in the last 90 days. We re-verify nightly.

What can J-Link MCP do?

With this server connected, an agent can capture full device state: registers, fault status, stack dump, RTT output, scan for connected probes and show the configured target, read a peripheral's registers and decode each one's bit fields by name, and read memory at address (clean hex dump output).

How do I install J-Link MCP?

Run `npx -y jlink-mcp`. The README documents 4 environment variables (PROBE_TYPE, OPENOCD_INTERFACE, OPENOCD_TARGET…) to set first. Set PROBE_TYPE, OPENOCD_INTERFACE, OPENOCD_TARGET, BMP_SERIAL_PORT before connecting. You can also paste the ready-made client config above.

Does J-Link MCP run locally?

Yes - it's a stdio server: it runs on your machine (via npx) with your user's permissions. Your data stays local unless the server itself calls external APIs.

07 · Alternatives to J-Link MCP