io.github.gjlmoteaPublished by GitHub account gjlmoteav0.1.0Updated Nov 8, 2026
Pre-print checks for Bambu Studio: GUI-faithful CLI slicing, override audit, printability.
Local MCP server that lets an assistant check, slice and audit 3D models against Bambu Studio presets before printing.
Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.
Follow the launch instructions in the repository.
English | 繁體中文
Slicewise lets Claude Code, Codex, Gemini CLI or any other Model Context Protocol client work with Bambu Studio's presets, slicer and model checks: find out whether a model will fail before you print it, decide which settings to change and why, then audit the sliced result to see which settings actually took effect.
It does not control printers. No MQTT, no uploads, no starting prints.
inherits, so slicing a stock preset from the CLI silently falls back to built-in defaults. Slicewise flattens the inheritance chain (and the per-printer G-code templates) first, then reads the sliced 3MF back and reports, override by override, whether each one was honoured.Unofficial. Not affiliated with, endorsed or sponsored by Bambu Lab. Tool descriptions and messages are in English.
bambu_diagnoseandbambu_plan_settingsalso match symptoms and goals written in Chinese (e.g. 翹邊, 省時).
Requires Node.js 22 or newer. Slicing needs Bambu Studio installed locally; the parameter and model tools work without it.
Claude Code:
Other clients (Codex, Gemini CLI, Cursor, Claude Desktop…):
Then ask the agent to call bambu_get_status: it shows the Bambu Studio data folder, whether the slicer was found, preset counts, the printer and filament currently selected in Studio, and the folders the model tools may read.
macOS privacy note. macOS restricts access to ~/Desktop, ~/Documents and ~/Downloads. If a model tool returns EPERM, grant the MCP host (the actual executable, e.g. the claude CLI rather than the Claude desktop app) access in System Settings and restart it, or point BAMBU_MODEL_DIR at an unrestricted folder.
16 tools, all prefixed bambu_.
Bambu Lab's stock presets are four-level inheritance chains. The leaf declares a few dozen keys and inherits the rest:
When a leaf preset is passed to the CLI with --load-settings, inherits is not resolved. Only the leaf's own keys apply; everything else falls back to the executable's built-in defaults, which are not Bambu Lab's stock values. Measured on an X1 Carbon 0.4 nozzle, 0.20mm Standard, Bambu PLA Basic, 20 mm cube:
This is the cause of bambulab/BambuStudio#1704 (CLI and GUI slicing differ).
Two more traps are handled:
system/BBL.json as <preset> template <key> entries. Following inherits alone ends at a generic start sequence that matches no Bambu printer. Slicewise applies the templates layer by layer; on a P2S 0.4 the resulting G-code is byte-identical to the GUI's.A real case: a birthday-cake topper built from boxes in Tinkercad. The legs ended at z = 50 mm and the body started at z = 51 mm. Bambu Studio reports "Levitating objects cannot be printed without supports", but enabling supports is the wrong fix: the support fills the 1 mm gap and the legs snap off when it is removed. Bounding boxes and overhang angles look fine; what matters is connectivity.
bambu_check_printability therefore:
Gaps of 2 mm or less are flagged as a likely modelling seam: fix the model with some overlap instead of adding supports. This is a rule of thumb, not a certainty: intentional print-in-place clearances (captive balls, hinges) land in the same range, so the report asks you to confirm the design intent. Wider gaps are real overhangs that need support.
Bambu Studio's negative parts, modifiers and support controls are not mesh edits. They are extra parts with a subtype label in the 3MF:
So bambu_compose_model needs no boolean engine and no GUI automation. It accepts exactly five subtypes, taken from ModelVolume::type_to_string() in Bambu Studio's source: normal_part, negative_part, modifier_part, support_blocker, support_enforcer. The list is closed on purpose. Studio's reader silently treats an unknown string as a solid part, so a one-letter typo turns "cut this away" into "add this as solid" with no error. Measured on a 20 mm cube with the same body on top: no part, 20.00 mm tall; negative_part, 15.00 mm; normal_part, 25.00 mm.
BAMBU_MODEL_DIR (and the output folder) are refused, including .. traversal and same-prefix neighbours (/models-evil does not pass a check for /models).bambu_diagnose says so when a symptom is unknown and lists the ones it knows, because a wrong guess can make things worse.bambu_measure_clearance reads 3MF and OBJ; an STL is one undivided soup of triangles, and the tool says so instead of returning an empty report.bambu_inspect_project reads any Bambu project 3MF; bambu_compose_model always writes a new file.Bug reports with your OS, Studio version and printer are welcome.
The smoke test uses a fixture data folder, so it runs without Bambu Studio (including in CI). node scripts/verify-real-slicer.mjs runs the real slicer end to end and is deliberately not part of verify.
The ZIP reader and writer, STL and OBJ parsers and 3MF builder are hand-written; the only runtime dependencies are the MCP SDK and zod.
src/domain/parameters/known-keys.ts is generated: the 568 setting keys of a flattened Bambu Studio configuration, used to catch typos in overrides (Bambu Studio silently ignores unknown keys). Regenerate it when a Bambu Studio release adds parameters:
It is not every key of every printer: multi-nozzle and other models may have extra keys, so an unknown key is reported as a warning, not an error.
MIT. Bambu Lab, Bambu Studio and MakerWorld are trademarks of Bambu Lab. Thingiverse and Printables are trademarks of their respective owners. This project is not affiliated with or endorsed by any of them. It runs Bambu Studio's command-line interface as a separate process and contains no Bambu Studio (AGPL-3.0) code.
Source: README.md at commit b324cf3
Get Bambu Studio companion status
Reports the BambuStudio data directory, whether the slicer executable is available, preset counts, the machine and filaments currently selected in Studio, the allowed model directories, and the integration level of each model platform. Use it first to see what this server can do on this machine. No side effects.
Takes no parameters.
List presets
Lists machine, process or filament presets. By default only presets selectable in the UI are returned; intermediate presets that exist only to be inherited from (e.g. fdm_process_common) are filtered out. Names listed here do not show real setting values; use bambu_resolve_preset for that. No side effects.
kindrequiredlimitsearchincludeAbstractFlatten a preset inheritance chain
Flattens a preset's inherits chain into the complete settings and records which level each value comes from. A BambuStudio leaf preset usually declares only a few dozen keys and inherits everything else from its parents, so to know the real value of any parameter you must look at the flattened result, not the leaf preset file. Use this whenever you need an actual setting value. No side effects.
keyskindrequirednamerequiredCompare two presets
Flattens two presets of the same kind and lists the settings that differ. Use it to answer questions like "what exactly is the difference between 0.20 Standard and 0.20 Strength" without reading four levels of JSON by hand. No side effects.
kindrequiredleftrequiredlimitrightrequiredExplain parameters and their trade-offs
Explains what a parameter does, its unit, its typical range, the cost of raising or lowering it, and related parameters. Call this before changing any parameter, instead of tuning by what merely sounds reasonable. No side effects.
keysgroupDiagnose a print failure from its symptom
Takes an observed symptom (warping, stringing, layer separation, elephant's foot, holes in the top surface, ...) and returns an ordered list of remedies, each with its mechanism, a suggested value and its cost. Use it when the user describes what went wrong rather than which parameter to change; apply one remedy at a time. If no known symptom matches, it says so instead of guessing. It also points out problems that no parameter can fix. No side effects.
symptommaterialsymptomIdPlan settings for a goal
Given what you want (safe and failure-free / fast / strong under load / good surface / economical), returns ordered parameter adjustments grouped by what they counter: adhesion and warping, nozzle collisions, surface quality, structural strength, time, filament. Each move includes its mechanism, a suggested value, its cost, and **the actual value in the current preset and its shape** (per-extruder parameters must be overridden with an array; a scalar is silently not applied). If modelPath is given, a printability analysis runs first and conditional adjustments are added based on the geometry. This is for planning before a print; to work back from a print that already failed, use bambu_diagnose. It only returns a plan and changes nothing. No side effects.
goalgoalIdmaterialmodelPathprocessPresetfilamentPresetCreate a stabilised print-in-place preset
Creates an auto-stabilised copy of the given (or currently selected) process preset that can be used directly in Bambu Studio. Use it when small print-in-place parts detach from the bed or get dragged off by the nozzle. It applies exactly: first-layer outer wall 20 mm/s, first-layer infill 30 mm/s, outer wall capped at 60 mm/s, slowdown for overhangs, avoid crossing printed walls, Monotonic line, and ironing and Fuzzy Skin turned off. If the source is an existing user preset, its leaf-level calibrations (dimensions, elephant's foot, etc.) are kept, but the new file still inherits directly from the system preset. By default Auto Brim is explicitly turned off so the brim does not fuse gear clearances; Brim Ears can be requested explicitly, and you will still be reminded to check the first layer. It does not change filament temperature, cooling or flow, because regular PLA and Silk PLA must be calibrated separately. Writes a file to the user profile directory; takes effect after Bambu Studio is restarted.
nameoverwriteprocessPresetincludeBrimEarsSave a user preset to Bambu Studio
Creates a custom preset that inherits from a system preset, in the BambuStudio user profile directory; it appears in the dropdown after Bambu Studio is restarted. BambuStudio has no plugin API (see bambulab/BambuStudio#9614), so this is the only way to get parameters tuned by an AI into the GUI. Writes a file; an existing preset with the same name is never silently overwritten.
kindrequirednamerequiredinheritsrequiredoverridesrequiredoverwriteSlice (after flattening the inheritance chain)
Slices with the BambuStudio CLI and reports real statistics: layer count, print time, filament weight. Presets are flattened before they are passed to the CLI; feeding the raw presets to the CLI makes every inherited parameter fall back to the built-in default (BambuStudio#1704), so do not call the CLI directly. After slicing, it reads the settings that actually took effect back from the output and audits each override you requested; an overrideAudit entry with honoured = false was not applied. Starts a child process and writes a .gcode.3mf to the configured output directory. It does not send anything to a printer or start a print.
platemodelPathrequiredoverridesplacementmachinePresetprocessPresetreportSettingsfilamentPresetsInspect model geometry
Parses an STL (binary or ASCII), 3MF or OBJ and reports triangle count, bounding box, volume, surface area, and whether the mesh is closed. The format is detected from the file content, not the extension. For 3MF and OBJ it also reports the part count and part list (3MF coordinates have the placement transform applied; OBJ is split into parts by o / g, and Tinkercad's colour export is OBJ). Reads only files inside the allowed directories. No side effects.
modelPathrequiredCheck printability
Finds problems visible before slicing: exceeding the build volume, floating bodies that do not touch the plate, an unclosed mesh, the share of steep overhangs, too small a base area, too high an aspect ratio, features that are too thin, and warping risk on large bottom surfaces. Each finding lists the related parameters. Floating detection splits the mesh into shells, merges shells that touch or intersect into bodies, merges shells fully enclosed by another body into it, then checks whether each body reaches the plate and measures the gap to the nearest body: a narrow gap means the parts were not joined in the model (turning on support would make them print as separate pieces); only a wide gap really needs support. Accepts STL, 3MF and OBJ. This is geometric analysis, not a slicing simulation; thin walls inside the model only show up when actually sliced. No side effects.
modelPathrequiredbuildVolumelineWidthMmoverhangThresholdDegreesMeasure clearance between parts
Measures the smallest clearance between the parts in a 3MF or OBJ, to judge whether a print-in-place mechanism will fuse when printed. Parts that touch each other are first merged into rigid bodies before comparing, because Bambu also stores the colour-change segments of a single solid as separate parts; without merging, one piece would be reported as "clearance 0". When the clearance is too small it suggests compensation, distinguishing outer contours from holes (the enclosed side is a hole to the slicer and is controlled by a different parameter). STL has no part boundaries, so it cannot be measured. No side effects.
modelPathrequiredsamplingMmreportThresholdMmminimumClearanceMmCompose a 3MF with negative / modifier parts
Builds a Bambu project 3MF from a base body STL plus extra parts. A negative part (negative_part) cuts away where it overlaps, a modifier (modifier_part) applies different settings to its region, and support_blocker / support_enforcer control support. In a Bambu model each of these is just one more part with a label, so no geometry (boolean) engine is needed. The output can be read back item by item with bambu_inspect_project, or passed straight to bambu_slice. Writes a file to the output directory.
namerequiredpartsrequiredbaseNamebasePathrequiredplateCentreRead back the part structure of a 3MF
Reads the objects and parts from a Bambu project 3MF, including each part's subtype and per-part settings. Use it to verify that what was written is really in the file; this is the key advantage of working with files over the GUI: you can compare item by item instead of only looking at the screen. It also flags subtypes that BambuStudio does not recognise. No side effects.
projectPathrequiredSearch for 3D models
Searches for models across platforms. Thingiverse uses its official API (requires THINGIVERSE_TOKEN). MakerWorld and Printables have no official public API, so for them only a search link is returned for a person to open; this is a deliberate downgrade: no scraping or private endpoints pretending to be an API. Do not claim to have searched or downloaded models from those platforms. Does not download any model. Accesses the internet.
limitqueryrequiredsources90% of the applicable checks met
How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.
Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.
claude mcp add slicewise \ -e BAMBU_MODEL_DIR="$HOME/Desktop/bambu-work" \ -e BAMBU_OUTPUT_DIR="$HOME/Desktop/bambu-work/out" \ -- npx -y @gjlmotea/slicewise-mcp{ "mcpServers": { "slicewise": { "command": "npx", "args": ["-y", "@gjlmotea/slicewise-mcp"], "env": { "BAMBU_MODEL_DIR": "/Users/you/Desktop/bambu-work", "BAMBU_OUTPUT_DIR": "/Users/you/Desktop/bambu-work/out" } } }}0.20mm Standard @BBL X1C <- fdm_process_single_0.20 <- fdm_process_single_common <- fdm_process_common<part id="2" subtype="negative_part"> <metadata key="name" value="hole"/></part>pnpm installpnpm verify # typecheck, 226 tests, build, stdio smoke testsrc/ domain/ pure logic: preset flattening, parameter knowledge, slicing audit, model geometry, 3MF ports/ PresetStore, Slicer, ModelCatalog adapters/ Bambu Studio CLI, preset store, Thingiverse, hand-off catalogs application/ BambuService server/ tool registration and schemasnode scripts/verify-real-slicer.mjs # writes a .gcode.3mf# take the key list from Metadata/project_settings.config in that file and overwrite known-keys.ts