bambu-printer-mcp

STL Manipulation Tools

All STL tools load the full mesh geometry into memory. For files larger than 10 MB, monitor memory usage and prefer testing on smaller files first.

get_stl_info

Inspect an STL file without modifying it. Returns bounding box dimensions, face count, vertex count, and model center.

{
  "stl_path": "/path/to/model.stl"
}

scale_stl

Scale an STL model along individual axes. Omit any axis to leave it unchanged (defaults to 1.0).

{
  "stl_path": "/path/to/model.stl",
  "scale_x": 1.5,
  "scale_y": 1.5,
  "scale_z": 1.0
}

For uniform scaling, set all three axes to the same value:

{
  "stl_path": "/path/to/model.stl",
  "scale_x": 2.0,
  "scale_y": 2.0,
  "scale_z": 2.0
}

rotate_stl

Rotate an STL model around one or more axes. Angles are in degrees. Omitted axes default to 0.

{
  "stl_path": "/path/to/model.stl",
  "angle_x": 0,
  "angle_y": 0,
  "angle_z": 90
}

extend_stl_base

Add solid geometry underneath the model to increase its base height. Useful for improving bed adhesion on models with a small or unstable footprint.

{
  "stl_path": "/path/to/model.stl",
  "extension_height": 3.0
}

extension_height is in millimeters.

merge_vertices

Merge vertices that are closer together than the specified tolerance. This can close small gaps in a mesh and slightly reduce file size. Useful as a cleanup step before slicing.

{
  "stl_path": "/path/to/model.stl",
  "tolerance": 0.01
}

tolerance is in millimeters and defaults to 0.01 if omitted.

center_model

Translate the model so the center of its bounding box sits at the world origin (0, 0, 0). Useful before applying transformations or exporting for use in another tool.

{
  "stl_path": "/path/to/model.stl"
}

lay_flat

Identify the largest flat surface on the model and rotate the model so that face is oriented downward on the XY plane (Z = 0). This is a common preparation step before slicing to minimize the need for supports.

{
  "stl_path": "/path/to/model.stl"
}

Note: this works best on models with a clearly dominant flat face. Results on organic or rounded shapes may be unpredictable.

Printer Control Tools

All printer tools accept optional host, bambu_serial, and bambu_token arguments. If omitted, values fall back to the environment variables PRINTER_HOST, BAMBU_SERIAL, and BAMBU_TOKEN. Passing them explicitly is useful when working with more than one printer.

The server also accepts the alias variables BAMBU_PRINTER_HOST, BAMBU_PRINTER_SERIAL, and BAMBU_PRINTER_ACCESS_TOKEN, plus BAMBU_PRINTER_MODEL and BAMBU_STUDIO_PATH.

get_printer_status

Retrieve current printer state including temperatures, print progress, layer count, time remaining, and AMS slot data. Internally sends a push_all MQTT command to force a fresh status report before reading cached state.

{
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

Chamber status decodes the current temperature from newer firmware’s packed CTC reports, including P2S, while retaining legacy chamber/frame fields.

Returns a structured object with fields including status (gcode_state string), temperatures.nozzle, temperatures.bed, temperatures.chamber, print.progress, print.currentLayer, print.totalLayers, print.timeRemaining, and ams (raw AMS data from the printer).

get_printer_filaments

Read the live AMS inventory and resolve each loaded tray to Bambu Studio filament profile JSON paths when bambu_model is known. The result includes a summary, per-slot display labels, profile match confidence, and a recommended load_filaments value for simple single-material CLI slicing.

{
  "bambu_model": "h2d",
  "nozzle_diameter": "0.4",
  "host": "192.168.1.100",
  "bambu_serial": "094...",
  "bambu_token": "your_access_token"
}

High-signal fields:

• summary.loaded_slots, summary.resolved_profile_slots, summary.unresolved_loaded_slots, summary.empty_slots
• trays[].display_name, trays[].tray_color, trays[].remain_percent
• trays[].resolved_profile_path
• trays[].profile_resolution: exact-model-nozzle, model, generic, or unresolved
• trays[].match_confidence: high, medium, low, or none
• recommended.load_filaments: the profile path the MCP will use for auto-slicing when no explicit filament override is provided

list_printer_files

List files stored on the printer’s SD card. Scans the cache/, timelapse/, and logs/ directories and returns both a flat list and a directory-grouped breakdown.

This is a read-only query: it never creates directories. Optional directories absent from a successful root listing return empty lists. Authentication, TLS, permission, and transfer failures are reported as errors rather than empty or partial results.

{
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

camera_snapshot

Capture a single JPEG frame from the printer’s chamber camera. Read-only.

Two transports are wired in, picked by bambu_model:

• TCP-on-6000 for A1, A1 mini, P1S, P1P. Native protocol per OpenBambuAPI/video.md: TLS on port 6000, 80-byte auth packet (bblp + access token), repeating 16-byte frame header + JPEG payload. The printer first replays the last frame it buffered, which after an idle period can show the chamber as it was long ago, so the tool skips that frame and returns the next live one (about 3 s). If no live frame follows within timeout_ms, it fails instead of returning a possibly stale image.
• RTSP for X1, X1 Carbon, X1E, P2S, X2D and H2, H2S, H2D, H2C, H2D Pro. Shells out to ffmpeg with rtsps://bblp:<token>@<host>:322/streaming/live/1 -frames:v 1. The H2 series wasn’t documented in OpenBambuAPI’s video.md but its firmware uses the same RTSP endpoint as X1 (verified live against an H2S, 2026-04-27).

Requires ffmpeg in PATH for the RTSP path. Install with brew install ffmpeg on macOS. Configure a trusted custom binary with the server-side FFMPEG_PATH environment variable, or set MCP_ALLOW_EXECUTABLE_ARG=1 before using the ffmpeg_path tool argument. The TCP-on-6000 path uses native Node TLS and does not require ffmpeg.

{
  "save_path": "/tmp/snap.jpg",
  "timeout_ms": 8000,
  "bambu_model": "h2s",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

Returns { status, format: "image/jpeg", sizeBytes, base64, savedTo?, transport }. transport is "tcp-6000" or "rtsps-322" so callers can tell which path produced the frame. Pass save_path to also write the bytes to disk; otherwise only the base64 payload is returned.

camera_stream_start, camera_frame, camera_stream_stop

Development capability; discover these tools before using them with an installed server. Start one shared camera connection while a viewer is open, then request changed frames. The connection closes after 30 seconds without a viewer request. Snapshots reuse its latest frame. A1/P1 use the existing TLS protocol; X1/H2/P2S use one ffmpeg process for the stream lifetime.

{"fps": 1, "idle_timeout_ms": 30000, "bambu_model": "p1s"}

Pass the usual optional host, bambu_serial, and bambu_token overrides to each tool. camera_stream_start returns {status: "started" | "running", transport, fps, startedAt}. Then call camera_frame with, for example, { "since_seq": 0, "wait_ms": 10000, "max_width": 300, "max_bytes": 20000 }. A changed frame returns JPEG base64, seq, dimensions and capture time. Keep the last delivered seq on unchanged; those replies carry no image. max_width preserves aspect ratio; optional max_bytes caps JPEG bytes by downscaling further (base64 adds about one third), and changed_only defaults to true with a 0.02 normalized thumbnail threshold.

Stop requests close the shared connection immediately, affecting every viewer of that printer; normally let idle expiry close it. Other printers keep their own connections. These tools send no motion, heating or print commands. See the camera stream contract for limits, cancellation, availability and lifecycle details.

delete_printer_file

Delete a single file from the printer’s SD card via FTPS. Destructive. Requires confirm: true — without it the call returns status: "skipped" and does not contact the printer. Path traversal segments (..) are rejected. Only files under cache/, timelapse/, and logs/ can be deleted.

{
  "filename": "old_print.gcode.3mf",
  "confirm": true,
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

A bare filename defaults to cache/<filename>. To target other directories pass a relative path:

{ "filename": "timelapse/2026-04-26_12-00.mp4", "confirm": true }

{ "filename": "logs/printer.log", "confirm": true }

upload_gcode

Write G-code content from a string directly to the printer’s cache/ directory. The content is written to a temporary file and uploaded via FTPS.

{
  "filename": "calibration.gcode",
  "gcode": "G28\nM104 S210\nG1 X100 Y100 Z10 F3000\n",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

upload_file

Upload a local file (G-code or 3MF) to the printer. If print is true and the file is a .gcode file, start_print_job is called automatically after a successful upload. For .3mf files, upload completes normally but you must use print_3mf to initiate the print (which handles plate selection and metadata).

{
  "file_path": "/Users/yourname/Downloads/part.3mf",
  "filename": "part.3mf",
  "print": false,
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

start_print_job

Start printing a .gcode file that is already on the printer’s SD card. Do not use this for .3mf files – use print_3mf instead, which handles the project_file MQTT command with proper metadata.

{
  "filename": "cache/calibration.gcode",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

If filename does not include a directory prefix, the server prepends cache/ automatically.

cancel_print

Cancel the currently running print job. Sends Bambu Studio’s stop, {"print":{"command":"stop","param":"","sequence_id":"<n>"}}, at MQTT QoS 1, and waits up to 10 seconds for the printer to acknowledge it. A stop that isn’t acknowledged returns an error, and its MQTT client is closed so it can’t be sent late. Not resumable — use pause_print if you may want to continue.

{
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

pause_print

Pause the currently running print job. Sends an UpdateState MQTT command with state: "pause". Resumable via resume_print.

{
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

resume_print

Resume a paused print job that this server inspected and started. Resume reheats and moves the printer, so it is checked like a print start:

1. A fresh report must show that job paused, with the inspected nozzle and filament still in place.
2. The server downloads the job’s file from the printer over FTPS and compares its SHA-256 with the inspected bytes. A P1S deletes an uploaded project once it starts printing and keeps the plate G-code it extracted, cache/<name>_plate_<n>.gcode, which is byte-identical to the 3MF’s Metadata/plate_<n>.gcode. When the project is gone, the server compares that file with the inspected plate. A different file refuses the resume, and the job can no longer be resumed from here.
3. The resume starts without a prompt when the bytes were verified. Only a file that could not be re-read asks a person; that prompt names the job, its peak temperatures, materials and SHA-256.
4. The printer is read again, and on X2D and H2 the native helper rechecks it once more right before sending. Only then does the server send UpdateState with state: "resume".

The server keeps one resume record per printer. Cancelling the job ends it, and so does a report that the job finished, failed or went idle after it was seen running, or another job seen in its place. A later job with the same name, such as the same file reprinted from the touchscreen, is never resumed. The server watches every MQTT report it receives, not just its own reads. It doesn’t see reports while its MQTT session is disconnected.

The result is {status, message, jobName, bytesVerified}, where jobName is the name counterpart_print_progress reports. On the BambuNetwork and X2D native routes, Bambu’s plug-in puts the file on the printer, so its FTPS path isn’t verified. If the file can’t be read back there, the resume matches the job by its unique name and returns bytesVerified: false, and a person is asked, with the prompt saying so. On every other route, a file that can’t be re-read refuses the resume.

{
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

clear_hms_errors

Clear HMS or print error state on the printer. Sends Bambu’s clean_print_error MQTT command.

{
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

set_print_speed

Set the active print speed mode. Accepted mode values are silent, standard, sport, ludicrous, or their numeric equivalents 1, 2, 3, and 4.

{
  "mode": "sport",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

set_airduct_mode

Set H2/P2 airduct mode to cooling or heating. This is intended for supported printers only.

{
  "mode": "cooling",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

reread_ams_rfid

Trigger a Bambu AMS RFID re-read for one AMS slot. This can move AMS filament; use it only when the printer is idle and unloaded.

{
  "ams_id": 0,
  "slot_id": 1,
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

set_temperature

Set a checked target temperature for the bed or nozzle through MQTT. Positive targets require the printer model and fresh matching printer telemetry; nozzle heating also requires the declared loaded material and matching nozzle_diameter (default 0.4). Independent model/component and material ceilings apply. A target of zero turns the heater off without requiring material or nozzle metadata. Accepted component values are bed, nozzle, extruder, tool, and tool0.

Manual nozzle heating checks the reported currently loaded AMS tray or external spool. It refuses ambiguous active-nozzle/material selection on multi-nozzle printers; use a checked sliced job or the printer’s own controls there. Stop and heater-off commands cancel pending server print/heating operations. Resuming through MCP requires the same paused job inspected and started by this server instance, with fresh matching telemetry; other paused jobs remain controllable at the printer.

{
  "component": "nozzle",
  "temperature": 220,
  "bambu_model": "p1s",
  "material": "PLA",
  "nozzle_diameter": 0.4,
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

set_fan_speed

Set a printer fan speed from 0 to 100 percent. Accepted fan values are part, auxiliary, chamber, 1, 2, and 3.

{
  "fan": "chamber",
  "speed": 40,
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

set_light

Set a printer light node mode. Common Bambu firmware reports the chamber light as chamber_light; valid modes are on, off, and flashing.

{
  "light": "chamber_light",
  "mode": "on",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

skip_objects

Skip specific object IDs during a running multi-object print. Use list_3mf_plate_objects on the sliced 3MF to find the IDs first.

{
  "object_ids": [6495, 6496],
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

set_ams_drying

Start or stop the AMS filament drying cycle on heated AMS units (AMS Pro / AMS-HT). The action parameter accepts start or stop. The ams_id must be an integer from 0 to 3.

{
  "action": "start",
  "ams_id": 0,
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token"
}

To stop drying:

{
  "action": "stop",
  "ams_id": 0
}

inspect_print_file

Inspect a prepared sliced 3MF or textual G-code file offline before deciding what to export or print. This tool copies the file into a private read-only snapshot and reuses the same archive, selected-plate, model/nozzle/material and temperature checks used by print preflight. It never contacts a printer or auto-slices an unsliced project.

{
  "file_path": "/path/to/bracket.gcode.3mf",
  "bambu_model": "p1s",
  "plate_index": 0,
  "nozzle_diameters": [0.4],
  "bed_type": "textured_plate"
}

file_path and explicit bambu_model are required; the model is never inferred from configuration. plate_index is zero-based and defaults to 0. Nozzle/bed checks are optional comparisons against file declarations, not observations of installed hardware. Only these five argument names are accepted; credentials, host and executable/bridge overrides are not part of this tool.

The generic result has receipt_version: "1", evidence: "file-only", dispatch_authorized: false, artifact (sha256, byte_length, file_format), the requested selection, and the original inspection including declared model, nozzles, materials/used filament positions, internal plate path and checked temperature peaks. Hash and byte length identify the exact inspected snapshot; a consumer must compare them with its own artifact and selected plate. The temporary snapshot is removed, and its path is not a dispatch capability. The receipt does not prove printer readiness, physical material/nozzle contents, fit, full motion simulation or permission to print. Actual print routes still independently inspect the dispatched snapshot and require fresh hardware state.

Print options

Every print route sends the options Bambu Studio’s Send dialog sends (Bambu Studio 02.08.02.61, SelectMachine.cpp:3344-3356): bed leveling, flow calibration and nozzle offset calibration, vibration calibration, first-layer inspection and extruder_cali_manual_mode. That covers the BambuNetwork bridge, the native helper and LAN project_file. Each option you don’t pass resolves as Studio resolves it:

1. Studio’s saved choice for that printer type in BambuStudio.conf, if the printer offers it. For example, a P1S offers only on/off for bed leveling, so a saved “auto” counts as unset.
2. Otherwise “auto” if the printer offers it, else “on”. On a P1S, flow calibration and nozzle offset calibration are hidden, so they stay “auto”.

Studio hard-codes vibration calibration off, first-layer inspection on and extruder_cali_manual_mode 0. For a P1S with nothing passed, the bridge sends task_bed_leveling: true, auto_bed_leveling: 1, task_flow_cali: false, auto_flow_cali: 2, task_vibration_cali: false, task_layer_inspect: true, auto_offset_cali: 2 and extruder_cali_manual_mode: 0. An option you pass wins. bed_leveling/flow_calibration set “on” or “off”, and auto_bed_leveling, auto_flow_cali and auto_offset_cali take 0 (off), 1 (on) or 2 (auto). On the H2/P2S LAN project_file route, the printer only receives flow calibration as on or off: no verified field requests “auto”, so “auto” sends off, as before. The BambuNetwork and native routes carry auto_flow_cali. Only the printer type’s own section of BambuStudio.conf is read; the file also holds access codes. BAMBU_STUDIO_CONFIG names another file, and an empty value uses no saved choices.

print_3mf

The primary tool for starting a Bambu print. Recommended input: a pre-sliced .gcode.3mf exported from FULU OrcaSlicer-bambulab, OrcaSlicer, or Bambu Studio — see slicing guide. This tool handles the complete workflow:

1. Checks whether the 3MF contains embedded G-code (Metadata/plate_<n>.gcode entries).
2. If no G-code is found, attempts to auto-slice via the configured slicer. Profile preparation or slicing failures stop the operation before upload. See the slicing guide for tested CLI versions and combinations.
3. Parses the sliced 3MF to extract the correct plate file and compute its MD5 hash.
4. Reads slicer metadata and any explicit AMS selection to build the filament mapping.
5. Uploads via basic-ftp to the model-specific location: SD root for H2/full-size A1, cache/ for P1/X1/A1 mini/P2S. X2D print_3mf instead uses its checked native route on macOS or Linux, which stores the job on a ready SD card or USB stick and otherwise on internal storage (eMMC).
6. Sends the correct MQTT print command for the target printer family. For H2S/H2D/H2C that means project_file with project-length ams_mapping, parallel ams_mapping2, and H2-compatible calibration flags.

{
  "three_mf_path": "/Users/yourname/Downloads/bracket.3mf",
  "bambu_model": "p1s",
  "bed_type": "textured_plate",
  "host": "192.168.1.100",
  "bambu_serial": "01P00A123456789",
  "bambu_token": "your_access_token",
  "bed_leveling": true,
  "flow_calibration": true,
  "vibration_calibration": true,
  "timelapse": false,
  "use_ams": true,
  "ams_mapping": [0, 1]
}

bambu_model is required for model-specific routing and preset selection. It does not by itself validate pre-sliced G-code. BambuStudio, FULU, and Orca CLI preparation additionally require the exact model/nozzle machine preset and reject incomplete profiles. Using the wrong model can damage hardware. If bambu_model is not provided in the tool call and BAMBU_MODEL is not set in the environment, the server will ask you interactively via MCP elicitation (if your client supports it) or return a clear error.

bed_type defaults to textured_plate if omitted. nozzle_type (stainless_steel, hardened_steel, tungsten_carbide, brass; default BAMBU_NOZZLE_TYPE) sets the installed nozzle when the project must be auto-sliced; the job’s nozzle type must match the printer’s report, and stock P1S/P1P/A1 presets assume stainless steel. nozzle_volume_type (standard, high_flow; default BAMBU_NOZZLE_VOLUME_TYPE) likewise sets the installed nozzle’s flow type for auto-slicing; it must match the printer’s reported nozzle flow. After an MQTT print command the server listens to the printer’s pushed reports for up to 15 seconds (BAMBU_DISPATCH_CHECK_MS) and returns dispatch: "started" or "unconfirmed"; if firmware 01.08.05+ refuses the command (HMS 0500-0500-0001-0007, needs LAN Only Mode and Developer Mode), the call fails and says so; clear that fatal HMS entry with clear_hms_errors before printing again. ams_slots is the preferred override input; ams_mapping remains the raw escape hatch. On AMS-equipped H2 printers, use_ams: false does not suppress mapping lookup if the sliced file declares filaments. If no mapping is provided for an H2 pre-sliced job with declared filaments, the server fails before sending; pass explicit ams_slots, raw ams_mapping, or auto_match_ams: true.

Set auto_match_ams: true to match the sliced 3MF’s tray_info_idx values against the live AMS inventory and use the matching ams_slots. The matcher joins on (tray_info_idx, tray_color) and tracks already-claimed slots, so prints with two filaments of the same SKU but different colors (e.g. two GFG02 PETG HF in black and white) resolve correctly. Falls back to SKU-only when the 3MF’s filament has no color set or only one tray of that SKU is loaded. Returns a structured missing report (reason: "no_loaded_match" | "color_mismatch" | "exhausted" | "no_sku") when a filament can’t be resolved. Ignored when you provide ams_slots or ams_mapping explicitly.

Layer height, nozzle temperature, and other slicer parameters cannot be overridden via this tool – they are baked into the 3MF’s G-code at slice time. Apply those settings in your slicer before generating the 3MF.

For the optional FULU bridge, set connection_mode: "bambu_network" and explicitly choose connection_type: "cloud" or "lan"; see FULU setup. A successful command submission is not proof that the printer accepted it: inspect printer state, HMS errors, and the printer itself.

bambu_network_bridge_status

Inspect the configured FULU bridge without starting it using {}. Use {"connect": true} to launch the host, handshake, and initialize an agent. See bridge probes for interpreting the result.

bambu_network_call

Call an allowed read-only probe such as {"method": "net.is_user_login", "payload": {}}. The default injects the initialized agent; use with_agent: false for bridge.handshake. Raw printer mutations and unknown methods are refused; use the dedicated checked print or printer tools.

X2D native transport (macOS)

Install Bambu Studio and its networking plug-in, plus the Apple command-line developer tools (clang++). The plug-in is loaded at runtime and is not redistributed. In the installed bambu-printer-mcp package directory, run npm run build:native. For a global install, locate that directory with npm root -g; for an extracted desktop extension, run the same command in the extension directory. Rebuild after updating the package. For Linux, see X2D native transport (Linux); Windows can use status and slicing only.

The npm package and desktop bundle include native/bambu-native-print.cpp, scripts/build-bambu-native.sh and the Linux setup script, never a developer’s compiled binary. The server finds the built helper relative to its installed package, regardless of the launch directory. A trusted server setting BAMBU_NATIVE_HELPER can select an alternate executable.

For X2D, print_3mf defaults to connection_mode: "bambu_native"; legacy lan_mqtt_ftps requests are redirected to it. Supply ams_slots, a complete project-level ams_mapping, or auto_match_ams: true. A job that uses only one external spool requires explicit use_ams: false; a job mixing AMS trays with the external spools maps them as 254 (left/deputy nozzle) and 255 (right/main nozzle). Raw ams_mapping2 and nozzle/extra-option overrides are rejected before dispatch; the server derives both AMS representations from the checked structured mapping. Model/nozzle/material inspection and fresh printer-state checks apply before the helper receives a private snapshot. The native helper requests fresh shared printer-state authorization immediately before each print submission, including a certificate retry, and before checked heating, resume, or error-clearing commands; custom helpers must support this handshake. Stop and heater-off remain available without preflight. Native upload-only requests use the same all-plate inspection as FTPS uploads. They accept project_name, preset_name, bed_type, and an existing plate_index; AMS, nozzle, and calibration print options are rejected. Use print_3mf for checked print settings.

The helper waits for connection/certificate exchange and retries only the initial -4030 send once. Rebuild the helper after upgrading to receive the teardown fix. A successful dispatch receipt ends the helper before plug-in cleanup can turn an accepted job into an error. If an older/custom helper crashes after dispatch, the server reports uncertainty: check the printer state and job name before retrying, because resending can duplicate a print. Previous hardware testing reached RUNNING on X2D; this revision is validated with mocked transport regressions and clean installs, not a new physical print. bambu_connect is an optional macOS handoff for user review in Bambu Connect and does not start a print. Native task, heater, and error controls retain the common safety checks; raw controls cannot bypass them. Request cancellation, stop, and heater-off interrupt pending native helpers; the server waits for process exit before releasing a checked file. A command already sent to the printer cannot be recalled by cancelling the request, so verify printer state before retrying.

X2D native transport (Linux)

On x86-64 Linux, one command builds the helper and installs Bambu’s networking plug-in and the Bambu Studio certificates. It needs a C++ compiler (g++ or clang++) and network access; no desktop or slicer is required:

npx -y -p bambu-printer-mcp bambu-printer-mcp-native-setup

Use the same package version as the server, for example [email protected]; when the installation is missing or stale, the server’s error names the exact command. The setup downloads the Linux plug-in that Bambu Studio itself installs, pinned to an exact version and SHA-256, and stores it with the certificates under ~/.config/bambu-printer-mcp/bambu-native (BAMBU_NATIVE_HOME or XDG_CONFIG_HOME move it; set the same value for the server). The plug-in is not redistributed by this package, and Bambu Studio’s own auto-updating copy is never used. The server finds the installation automatically and passes the plug-in and certificate paths to the helper. Rerun the setup with the server’s package version after upgrading: the server refuses a helper built from another version. Only missing or changed files are downloaded again. The setup then loads the plug-in once, offline, so missing system libraries are reported during installation rather than on a stop command. --verify repeats these checks without network access. On Linux the server uses only this managed helper or BAMBU_NATIVE_HELPER; a package-local npm run build:native binary is not used.

--check-update asks Bambu’s plug-in service for the newest Linux plug-in and compares the PrintParams layout in the matching Bambu Studio header with the helper. It reports only: the setup never installs an unpinned plug-in, because a changed layout would send wrong print parameters. A pin is raised by a package release after the check passes and the offered archive and required libraries are checksum-verified. Offline plug-in loading and physical X2D printing are separate validation steps, reported with each release.

Once the helper, plug-in and certificates are installed, X2D printing, upload and controls use the same routing, safety checks and authorization handshake described for macOS above. On Linux, stop and heater-off go out over the native route and MQTT at the same time, so a stuck helper cannot delay them. MQTT is sent again once every older print or heating helper for that printer has exited and the immediate MQTT attempt has settled, so none can dispatch after it; either the native route or that la