anycubic-slicer-mcp

An MCP server that lets AI agents (Claude Code, Claude Desktop, Cursor, …) use Anycubic Slicer Next without its GUI: list presets, slice models, read print time and filament estimates, and look at a rendered preview of the toolpaths.

Unofficial community project. Not affiliated with or endorsed by Anycubic.

You:    Slice examples/calibration_cube.stl for my Kobra S1 with 15% infill.
Agent:  slice_model → 20m 53s, 3.56 g PLA, 100 layers, first layer 24s
        preview_gcode(layer=1) → [PNG of the first layer, colored by feature]

examples/calibration_cube.stl is a plain 20 mm cube (regenerate it with python examples/make_cube.py).

Requirements

• Windows (the slicer's headless CLI and preset folders are used as installed by Anycubic)

• Anycubic Slicer Next installed and opened at least once

• Python 3.10+

Tested with Anycubic Slicer Next 2.0.0.3 on Kobra S1, S1 Max, Kobra 3 / 3 Max, Kobra 4, Kobra X, Kobra 2 Neo / 2 Pro and Kobra 1 presets. Presets are read from the slicer itself, so other Anycubic printers should work too.

Related MCP server: cura-mcp

Install

git clone https://github.com/EmreTekir/anycubic-slicer-mcp
cd anycubic-slicer-mcp
py -3 -m venv .venv
.venv\Scripts\python.exe -m pip install .

Register it with Claude Code (for all your projects):

claude mcp add --scope user anycubic-slicer -- "$PWD\.venv\Scripts\anycubic-slicer-mcp.exe"

Or in any MCP client config:

{
  "mcpServers": {
    "anycubic-slicer": {
      "command": "C:\\path\\to\\anycubic-slicer-mcp\\.venv\\Scripts\\anycubic-slicer-mcp.exe"
    }
  }
}

With uv you can skip the clone: uvx --from git+https://github.com/EmreTekir/anycubic-slicer-mcp anycubic-slicer-mcp

Environment variables

Tools

Settings are changed with overrides, e.g. {"sparse_infill_density": "20%", "enable_support": true, "brim_type": "outer_only", "nozzle_temperature": 215}. Each key is routed to the process, filament or machine config that owns it. Valid keys that no preset lists (such as ironing_inset) go to the process config. Keys the slicer doesn't know are rejected, and the result lists warnings for values the slicer clamped or ignored (for example a bed temperature key that doesn't match the selected plate type).

Multi-colour prints: give one model file per colour, the filaments, and which filament each model uses. Pass the colours of the loaded spools so the printer maps each filament to the right one:

{"models": ["body.stl", "logo.stl"], "filaments": ["Anycubic PLA", "Anycubic PLA Matte"],
 "object_filaments": [1, 2], "filament_colours": ["#FFFFFF", "#1E6FD9"]}

Each slice writes three files: <name>.gcode, <name>.gcode.3mf (G-code inside, for sending to the printer; the GUI shows it as a G-code preview) and <name>_project.3mf (no G-code, opens in the GUI as a project you can still edit). Overridden settings are recorded so the GUI keeps them instead of falling back to the preset values.

Notes:

• Filament names can be given naturally: with a printer selected, "Anycubic PLA" means Anycubic PLA @<that printer>.

• scale and rotate_z work on STL and OBJ files (the model is transformed before slicing).

• arrange=false keeps the coordinates stored in the file, so a model at the origin may land off the bed.

• Results are written next to the first model unless output_dir is given; existing files with the same name are replaced.

How it works

• Presets live as JSON under %APPDATA%\AnycubicSlicerNext\system\Anycubic\… and user\<folder>\…. Each may inherits a parent; the server merges the chain into the flat config the CLI expects. The active user folder and the GUI's selection come from AnycubicSlicerNext.conf.

• The CLI checks compatible_printers against the printer's system parent, so flattened user printers get that parent written back. Using a process or filament made for another printer works, and is reported as a warning.

• Anycubic filaments carry per-nozzle variants (nozzle_temperature_HS, _BRASS) that win over the plain key; setting the plain key updates them too.

• The slicer's own first-layer estimate is far too low, so first_layer_time is measured from the M73 progress marks when the G-code has them (first_layer_time_source says which was used).

• The slicer's own --scale above 1 and --rotate crash it, so models are transformed in Python.

• Tools run in worker threads: a long slice does not block other requests.

Safety

The server runs locally over stdio with your user's permissions. It is built so a confused or manipulated agent (for example one following instructions hidden in a downloaded file) cannot turn it into more than a slicer:

• post_process (programs the slicer runs after slicing) can never be set through the tools. 3MF files are scanned before they are sliced, inspected or opened, and refused if any settings entry carries a post-processing script or cannot be checked reliably.

• Raw G-code templates (machine_start_gcode, filament_end_gcode, …) are read-only unless you set ANYCUBIC_MCP_ALLOW_GCODE_TEMPLATES=1.

• Setting values may not contain line breaks or control characters, so a value that a G-code template expands (a filament type, a note) cannot smuggle in extra G-code lines.

• Network paths (\\server\share\…, mapped network drives) are refused before anything touches the filesystem, because merely opening one makes Windows send your credentials to that server.

• File tools only accept existing files with model or .gcode extensions. slice_model writes only .gcode / .gcode.3mf files; save_user_preset writes only into the slicer's user preset folder and cannot change a preset's name, parent or compatibility fields.

• Image size, timeout, copies, scale and plate number are bounded.

What it does not protect against:

• Your own presets: a user preset that already contains a post_process script (set up in the GUI) is used as-is, exactly as the GUI would use it.

• A 3MF sliced with use_project_settings brings its own start/end G-code, as it would in the GUI.

• Temperatures and speeds are ordinary settings and are passed through. Check what the agent sliced before you print it.

Development

.venv\Scripts\python.exe -m pip install -e .[test]
.venv\Scripts\python.exe -m pytest

The tests need no slicer install. Changes that touch slicing should also be checked against a real slicer with examples/calibration_cube.stl.

License

MIT