Orcaslicer MCP

What orcaslicer-mcp does

orcaslicer-mcp gives an MCP client control and read access to a live OrcaSlicer project. It can load STL, OBJ, and 3MF models, with STEP and STP support on the specified fork builds, then list, duplicate, delete, transform, arrange, or auto-orient objects on the active plate. It also exposes project configuration, preset-related operations, slicing controls, placement checks, and background-job status.

The slicing workflow covers both asynchronous and blocking use. An agent can start a slice and poll for progress, or wait for final statistics and warnings in one call. Results include print time and filament usage. Where the fork emits the required data, get_slice_breakdown adds per-feature time, filament, speed, and flow information, along with a prediction check for speeds limited by the flow ceiling.

How it works

The MCP server communicates with OrcaSlicer at a configured address, using localhost by default. The model is supplied by the MCP client; the package does not include one. Project changes are reflected in the running GUI. Configuration writes through set_config and apply_and_slice are atomic, but they create unsaved overrides rather than changing preset files. Selecting another preset discards those overrides, while save_preset can persist suitable changes after validation.

For controlled experiments, compare_settings tests multiple values for one key and restores the original value. compare_slices applies named variants independently over the original configuration, slices each one, and restores the prior configuration afterward. Its response includes structured results and precomputed comparisons against a baseline.

Offline setting tools help identify valid keys and values before editing. search_settings and find_config_keys locate candidates, while describe_setting returns a setting's type, unit, range, enum values, default, label, and tooltip. consult retrieves curated slicing guidance and saved context notes. check_profile_physics overlays proposed changes and evaluates flow, temperature, geometry, and cooling constraints before a preset is saved.

Tools and capabilities

• Inspect session, project, preset, slice, object, and background-job state.
• Load supported model files and manipulate objects by stable ID.
• Read or change merged OrcaSlicer configuration values.
• Slice synchronously or asynchronously, cancel stale jobs, and retrieve warnings.
• Compare settings or complete slice variants without leaving test changes applied.
• Diagnose plate fit using object footprints, skirt or brim expansion, and edge clearances.
• Query per-feature timing, filament use, flow ranges, and layer aggregates when available.
• Store machine, user, or project context notes in local plain files.

Limitations and notes

Configuration edits invalidate the previous slice, so a changed project should be sliced again before relying on earlier statistics. set_config does not perform the physics check automatically; temperature, speed, acceleration, and flow changes should be checked before trusting or saving a profile. Deleting an object is permanent within the session and cannot be undone through the API.

Placement checks are estimates based on object footprints and offsets rather than final sliced toolpaths. They exclude details such as skirt arcs, half-line-width effects, and travel or wipe moves, so near-boundary cases should also be checked through slice warnings. Warning completeness depends on what the connected OrcaSlicer fork exposes, and breakdown data can be unavailable when the fork does not emit it or when no valid slice exists.

Arrange and auto-orient run asynchronously; poll get_job_status until the worker is idle before reading positions or slicing. The server does not bundle an AI model. When printer tools are used, they make read-only requests and send no commands or uploads to the printer.