mcp-3D-printer-server

Abstracts 8+ distinct 3D printer APIs (Bambu Lab, OctoPrint, Klipper via Moonraker, Duet, Repetier, Prusa, Creality, Orca Slicer) behind a single MCP tool interface, translating normalized commands into printer-specific API calls and response schemas. Uses adapter pattern with per-printer protocol handlers that map common operations (start print, pause, resume, cancel, temperature control) to native API endpoints while normalizing heterogeneous response formats into consistent JSON structures.

Parses and modifies 3D model files (STL, 3MF formats) to perform structural operations including scaling, rotation, translation, and sectional editing. Likely uses a 3D geometry library (Three.js mentioned in tags) to load mesh data, apply transformation matrices, and serialize back to file format. Supports both ASCII and binary STL formats with format auto-detection and preservation of original file properties during round-trip operations.

Stores and manages printer profiles containing hardware specifications (bed size, nozzle diameter, max speeds), firmware settings, and slicing defaults. Enables quick printer registration with minimal manual configuration and provides configuration templates for common printer models. Supports configuration versioning and rollback to previous settings.

Polls or subscribes to printer status endpoints (temperature, print progress, nozzle position, bed state, error codes) and aggregates heterogeneous telemetry into normalized status objects. Implements per-printer polling intervals or webhook subscriptions depending on API capabilities (e.g., Klipper supports WebSocket subscriptions via Moonraker, OctoPrint uses REST polling). Maintains in-memory state cache to enable fast status queries without repeated API calls.

Invokes slicing engines (Orca Slicer, Bambu Studio, Prusa Slicer, Creality Slicer) via their native APIs or CLI interfaces to convert STL/3MF models into printer-ready G-code. Passes model files, printer profiles, and slicing parameters (layer height, infill, support type) to the slicer and retrieves generated G-code output. Handles slicer-specific configuration formats (e.g., Bambu's .3mf project files with embedded settings) and normalizes output G-code for target printer compatibility.

Renders STL/3MF models to 2D preview images or interactive 3D visualizations using Three.js, enabling LLMs and users to inspect models before printing. Generates orthographic or perspective projections, applies lighting and shading, and optionally overlays printer bed dimensions or support structures. May support multiple output formats (PNG, JPEG, WebGL canvas) depending on client capabilities.

Applies printer-specific transformations to G-code files before sending to printer, including firmware-specific command translation, coordinate system adjustments, and compatibility checks. Validates G-code syntax, detects unsupported commands, and optionally injects printer-specific preambles (e.g., bed leveling sequences, nozzle priming). Handles firmware variants (Marlin, Klipper, RepRapFirmware, Repetier) with different command dialects and parameter formats.

Manages a queue of print jobs with support for prioritization, scheduling, and automatic dispatch to available printers. Tracks job state (queued, printing, completed, failed) and implements simple scheduling logic (FIFO, priority-based, or round-robin across printers). Integrates with real-time status monitoring to detect when printers become available and automatically start next queued job. Supports job dependencies (e.g., print B only after A completes) and conditional logic based on printer state.

Monitors printer telemetry for error conditions (temperature faults, mechanical failures, connectivity loss) and implements recovery strategies (retry, pause, cancel, alert). Maintains printer-specific error code mappings to translate firmware error codes into human-readable diagnostics. Supports automatic recovery actions (e.g., resume after brief pause, retry failed command) with configurable thresholds and backoff strategies.

Exposes all 3D printer operations as standardized MCP tools with JSON schemas, enabling LLMs to discover and invoke capabilities through natural language. Generates tool descriptions, parameter schemas, and usage examples that guide LLM behavior. Implements tool validation to ensure LLM-generated parameters are within safe ranges (e.g., temperature limits, bed size constraints) before execution.

Modifies model geometry to extend or modify base structures for improved print stability. Adds raft-like extensions, thickens bases, or adjusts support contact points programmatically. Works with parsed STL/3MF mesh data to identify base geometry, compute extension vectors, and merge new geometry with original model. Supports both automatic base detection and manual specification of base regions.