Bambu Lab CLI for slicing and printing 3D models

Migrating the Python Print Operator? See the command and configuration guide.

Slice, check, send and monitor Bambu Lab prints from the terminal over your LAN. It's built for humans and for AI agents.

• Headless slicing: it drives the Bambu Studio CLI with the correct system presets for your printer and nozzle, plus recipes and--set overrides.
• Safety first: - Preflight gates check that the printer is idle, the right filament is in the slot, the plate and nozzle match, Developer Mode is on, and there's enough filament.
  • print send refuses to run without--confirm .
  • No command ever changes printer settings.
• LAN only: MQTT and FTPS go directly to the printer. No cloud account, no Bambu Connect.
• Agent-friendly:--json everywhere (NDJSON for streams), stable exit codes,schema introspection, and no prompts with--no-input .
• Single static binary for macOS, Linux and Windows.

$ bambu status
workshop (192.168.1.50)  IDLE / idle   dev_mode=true  sdcard=true  liveview=true
  temps    nozzle 26/0  bed 24/0   nozzle 0.4 mm hardened_steel
  errors   none
  AMS A1   PLA    PLA Matte    #FF6A13  33% (~330 g)
  AMS A2   PETG   PETG Basic   #FFFFFF  80% (~800 g)
  protect  first_layer=true spaghetti=true halt=true (medium)

$ bambu slice bracket.stl --recipe functional-petg
sliced  bracket-functional-petg
  time      35m 38s  (2138 s)
  filament  13.22 g PETG (GFG00)   layers 113
  temps     bed 70 C (textured_plate)   nozzle 252 C, first layer 252 C
  3mf       ./bracket-functional-petg.gcode.3mf

$ bambu print send bracket-functional-petg.gcode.3mf --slot A2 --dry-run   # preflight + exact payload, sends nothing
$ bambu print send bracket-functional-petg.gcode.3mf --slot A2 --confirm   # after you've checked the plate is clear
$ bambu monitor --snapshot-at-layer 2

• A Bambu Lab printer in LAN Only mode with Developer Mode enabled. Since the January 2025 "Authorization Control" firmware, the printer rejects unsigned third-party control commands otherwise.
  • On the printer, go to Settings → LAN Only , enableLAN Only Mode , thenDeveloper Mode . Note theaccess code shown there.
  • Developer Mode disconnects the printer from Bambu Cloud and the Handy app. That's Bambu's tradeoff, not ours.
  • Status (bambu status ) is read-only and works without Developer Mode. FTPS upload and control need it.
• On the printer, go to
• Bambu Studio installed, forslice .
• ffmpeg , for camera snapshots.
• Tested models: X1 Carbon. The X1/X1E/P1/A1/H2/P2S series use the same LAN protocol and should work, but they are untested. Camera snapshots are X1/H2/P2S-series only for now; P1/A1 use a different camera protocol.

brew install voska/tap/bambu            # macOS / Linux
go install github.com/voska/bambu/cmd/bambu@latest

Binaries for macOS, Linux and Windows are on Releases.

bambu printer discover                       # listens for the printer's SSDP broadcast (UDP 2021)
bambu printer add workshop --host 192.168.1.50 --serial 00M00A000000000 --model X1C --nozzle 0.4 --plate textured_plate

bambu auth set workshop                      # prompts; or: echo CODE | bambu auth set workshop

bambu auth status --check
bambu slicer info
bambu status

Config: ~/.config/bambu/config.toml (%AppData%\bambu\config.toml on Windows, or $BAMBU_CONFIG). Printers are named, and --printer/ BAMBU_PRINTER picks one. bambu only reads and writes config.toml, so it coexists with other tools that use ~/.config/bambu/config.json.

Access code: looked up in this order:

1. The OS keychain (service bambu , account = the printer serial)
2. BAMBU_ACCESS_CODE
3. Bambu Studio's BambuStudio.conf , as a last-resort fallback

It is never printed, and never written to the config.

bambu recipe list                                   # prototype-pla, solid-pla, functional-pla, functional-petg
bambu slice part.3mf --recipe solid-pla             # STL / 3MF / OBJ
bambu slice part.stl --recipe prototype-pla --set wall_loops=3 --filament "Bambu PLA Matte"
bambu camera snapshot -o plate.jpg                  # look at the plate
bambu preflight part-solid-pla.gcode.3mf --slot 4   # PASS/WARN/FAIL gates
bambu print send part-solid-pla.gcode.3mf --slot 4 --confirm
bambu monitor --snapshot-at-layer 2 --exec 'notify-send "$BAMBU_EVENT $BAMBU_STATE"'

A two-filament job changes colour at a layer height, and the AMS swaps by itself: no , nobody at the printer.

bambu slice sign.3mf --recipe prototype-pla \
  --filament "Generic PLA" --color FFFFFF --filament "Bambu PLA Matte" --color 000000 \
  --filament-change-z 4.0                           # white through Z 4.0, black from the next layer up
bambu print send sign-prototype-pla.gcode.3mf --slot A4 --slot A1 --dry-run   # one slot per filament, in order

• --filament-change-z must be a layer top.slice reads the change back from the G-code and fails (exit 11) if Bambu Studio didn't place it.
• The summary has grams per filament, including purge and prime-tower waste, and filament_changes .
• To change colour by hand at a (e.g. a spool that isn't in the job), bambu filament load --slot A1 --confirm swaps the toolhead to another AMS slot remotely, thenbambu print resume --confirm .

Recipes name presets generically ("0.20mm Standard", "Bambu PLA Basic"), and bambu resolves the right system preset for your printer model and nozzle.

• No recipe adds a brim. Brims are opt-in:--set brim_type=outer_only --set brim_width=5 .
• Custom recipes: drop JSON files in~/.config/bambu/recipes/ . The same name overrides a built-in. Seebambu recipe show solid-pla .
• --set key=value takes any Bambu Studio setting key. Unknown keys are rejected before slicing. At 100% infill, patterns the slicer rejects (grid, gyroid, …) switch to zig-zag automatically.

1. preflight checks before anything is sent: - the printer is idle, with no blocking errors (informational HMS codes like "Inspecting first layer" are ignored)

• Developer Mode is on and an SD card is present
• the 3MF is intact and sliced for this printer model, with one --slot per filament
• the nozzle diameter and plate match
• each slot is loaded with its filament's type (a different product of that type is a WARN)
• each slot has enough filament (unknown remaining is a WARN), and the temperatures are sane
• the printer's AI protections are on (WARN only) and FTPS login works

2. print send re-runs preflight and refuses on any FAIL. It requires--confirm , uploads over FTPS, reads the file back to verify its MD5, then starts the job with bed leveling, flow calibration, vibration compensation and first-layer inspectionon .
3. print |resume|stop require--confirm .resume exits 0 only once the printer reports RUNNING. It refuses mid-filament-change, and with an empty toolhead on the X1 series.
4. filament load requires--confirm and works only while d or idle. When d, the toolhead must hold an AMS filament and the slot must hold the same material. It exits 0 only once the printer reports that slot in the toolhead.

bambu has no command that changes printer settings.

bambu exit-codes

• bambu schema --json returns the full command tree with flags.bambu schema print send returns one command.

• Every command takes --json . Errors come back as{"error":{"code","name","message","hint"}} , and thehint says what to do next.

• status --watch --json andmonitor --json stream NDJSON events.

• There's an agent skill in skills/bambu/SKILL.md . The recommended flow: status → slice → dry-run → show the human the summary, preview and snapshot →--confirm only after explicit approval.

Bambu Studio is discovered in this order:

1. BAMBU_STUDIO_PATH /[slicer] path
2. /Applications/BambuStudio.app (macOS)
3. bambu-studio in the usual Linux paths, Flatpak, or an extracted AppImage
4. Program Files\Bambu Studio (Windows) Only macOS is tested. A packed AppImage can't be read, so extract it ( --appimage-extract ) or set[slicer] resources .

Presets are flattened by bambu. The Bambu Studio CLI does not resolve inherits /include in preset files. Unflattened presets slice "successfully" with a generic 200×200 bed and no printer start G-code. #

STEP is not supported by the Bambu Studio CLI. Export STL or 3MF instead. #

OrcaSlicer isn't supported yet. Its 2.4.x CLI has the sameinherits problem (fixed upstream after 2.4.2).

The LAN protocol details come from these open projects' public documentation and code. No code was copied.

• OpenBambuAPI (GFDL docs): MQTT, FTPS and video.
• ha-bambulab (MIT): HMS decoding, stage names,print.fun Developer Mode bit,project_file usage.
• bambulabs_api (MIT): implicit FTPS with TLS session reuse.
• Bambu Studio (AGPL-3.0): preset resolution order and AMS mapping format were read from its source;bambu invokes the installed app and ships none of its files.

Not affiliated with Bambu Lab. "Bambu Lab" is a trademark of its owner.

MIT