mcpXL30 0.1.0

FastMCP server exposing Philips XL30 ESEM controls via pyxl30 (unofficial)

mcpXL30

WORK IN PROGRESS

mcpXL30 is an MCP (Model Context Protocol) server that exposes a curated subset of the pyxl30 control library to LLM agents (i.e. AI contorl of the XL30 ESEM).

Note that this project was partially generated with LLM support.

Features

• Async MCP tools for common Philips XL30 operations (identify, read/set high tension, change scan modes, trigger pump/vent cycles, capture TIFF images).
• Live MCP resources that describe the connected instrument and active config.
• Safety envelope that limits accelerating voltage and sensitive operations.
• Fine grained settings that control allowed operations for the LLM agent.
• Optional remote HTTP/UDS transport with the authentication workflow explained in my blog post.

Installation

pip install .
# or
pip install ".[remote]"  # adds FastAPI/uvicorn/argon2 for remote mode

Configuration

The server loads JSON configuration from ~/.config/mcpxl30/config.json by default (override via --config). A minimal example:

{
  "instrument": {
    "port": "/dev/ttyUSB0",
    "log_level": "INFO",
    "retry_count": 3,
    "reconnect_count": 3
  },
  "image_capture": {
    "remote_directory": "C:\\\\TEMP",
    "filename_prefix": "MCPIMG_"
  },
  "safety": {
    "max_high_tension_kv": 15.0,
    "allow_venting": false,
    "allow_pumping": true,
    "allow_scan_mode_changes": true,
    "allow_stage_motion": false,
    "allow_detector_switching": true,
    "allow_beam_shift": true,
    "allow_scan_rotation_changes": true,
    "allow_image_filter_changes": true,
    "allow_specimen_current_mode_changes": false,
    "allow_beam_blank_control": true,
    "allow_oplock_control": false
  },
  "logging": {
    "level": "INFO",
    "logfile": null
  },
  "remote_server": {
    "uds": "/var/run/mcpxl30.sock",
    "api_key_kdf": {
      "algorithm": "argon2id",
      "salt": "<base64>",
      "time_cost": 3,
      "memory_cost": 65536,
      "parallelism": 1,
      "hash_len": 32,
      "hash": "<base64>"
    }
  }
}

Use mcpxl30-genkey --config /path/to/config.json (or mcpxl30 --genkey) to generate a new API key and populate the Argon2 hash inside the remote_server block. The plain token prints once to stdout.

The safety block gates riskier capabilities. Keep allow_stage_motion and allow_oplock_control disabled unless you trust the calling agent. Imaging and detector-related fields default to safe-but-capable settings, but you can toggle them per deployment.

Running the server

stdio transport (default)

mcpxl30 --config ~/.config/mcpxl30/config.json

The process utilizes the stdio transport.

Remote FastAPI/uvicorn transport

pip install "mcpXL30[remote]"
mcpxl30 --transport remotehttp --config ~/.config/mcpxl30/config.json

• The FastAPI app exposes /mcp (MCP streaming API) and /status (unauthenticated health check).
• Authentication expects the API key in Authorization: Bearer, X-API-Key, or the ?api_key= query parameter.
• Binding uses a Unix domain socket (remote_server.uds) unless you specify a TCP port, in which case host (default 0.0.0.0) applies.

MCP functionality

Tools

Instrument Basics

Tool	Purpose
instrument_identify	Return the microscopes type/serial, scan mode, high tension.
read_high_tension / set_high_tension	Inspect or change accelerating voltage (safety-capped).
get_scan_mode / set_scan_mode	Read or change scan mode (allow_scan_mode_changes).
capture_image / trigger_photo_capture	Store images (TIFF or console photo).
control_vent, pump_chamber	Chamber vent/pump control (safety gated).

Beam & Detector Controls

Tool	Purpose
get_spot_size / set_spot_size	Read or set probe current (1–10).
get_magnification / set_magnification	Read or set magnification (20–400 000).
get_stigmator / set_stigmator	Inspect/update stigmator X/Y.
get_detector / set_detector	Inspect or switch active detector (allow_detector_switching).
read_high_tension	Included above but relevant for beam tuning.

Scan Timing & Geometry

Tool	Purpose
get_line_time / set_line_time	Read or set line time (ms or TV).
get_lines_per_frame / set_lines_per_frame	Inspect or adjust lines per frame.
get_scan_rotation / set_scan_rotation	Read or set scan rotation (allow_scan_rotation_changes).
get_area_dot_shift / set_area_dot_shift	Manage area/dot shift percentages (allow_beam_shift).
get_selected_area_size / set_selected_area_size	Control selected area dimensions.

Imaging Utilities

Tool	Purpose
get_contrast / set_contrast	Read or set contrast (0–100).
get_brightness / set_brightness	Read or set brightness (0–100).
auto_contrast_brightness, auto_focus	Run built-in adjustment routines.
get_databar_text / set_databar_text	Inspect or update the image databar text.

Stage & Alignment

Tool	Purpose
stage_home	Home the stage (allow_stage_motion).
get_stage_position / set_stage_position	Read or move X/Y/Z/tilt/rotation (allow_stage_motion).
get_beam_shift / set_beam_shift	Inspect or adjust beam shift (allow_beam_shift).

Image Filtering & Specimen Current

Tool	Purpose
get_image_filter_mode / set_image_filter_mode	Manage FastMCP image filter + frame count (allow_image_filter_changes).
get_specimen_current_detector_mode / set_specimen_current_detector_mode	Inspect or change detector mode (allow_specimen_current_mode_changes).
get_specimen_current	Read specimen current (requires measure mode).

Beam Safety & Locks

Tool	Purpose
is_beam_blanked, blank_beam, unblank_beam	Inspect or control beam blank state (allow_beam_blank_control).
get_oplock_state, set_oplock_state	Inspect or control the operator lock (allow_oplock_control).

Every setter uses blocking pyxl30 calls inside asyncio.to_thread, preserving the FastMCP event loop responsiveness. Review the safety settings to enable only the tools you trust agents with.

All setters perform blocking pyxl30 calls inside asyncio.to_thread so the MCP event loop stays responsive.

Resources

• mcpxl30://instrument/capabilities – supported scan modes, image filter names, and the configured safety envelope.
• mcpxl30://instrument/config – sanitized live configuration (excludes API secrets).

Examples

An examples/example_config.json file is included to bootstrap deployments. The repository mirrors mcpMQTT's project layout so existing FastMCP infrastructure (supervisors, packaging, docs) can be reused with minimal changes.