dcc-mcp-3dsmax 0.1.5

3ds Max plugin for the DCC Model Context Protocol (MCP) ecosystem — embeds a Streamable HTTP MCP server directly inside 3ds Max

dcc-mcp-3dsmax

3ds Max plugin for the DCC Model Context Protocol (MCP) ecosystem.

Status: This project is under active development. APIs, packaging, and 3ds Max integration details may change quickly while the adapter tracks the latest dcc-mcp-core releases.

Features

• Sidecar MCP Server: Starts dcc-mcp-server.exe sidecar and keeps 3ds Max scene edits on the main thread
• Progressive Skill Loading: Discover skills without loading them immediately
• Shared Gateway: Registers with the stable gateway at http://127.0.0.1:9765/mcp
• Job Persistence: SQLite-based job storage for long-running operations
• Prometheus Metrics: Optional /metrics endpoint for monitoring

Installation

pip install dcc-mcp-3dsmax

Quickstart (inside 3ds Max MAXScript Listener)

import dcc_mcp_3dsmax

# Start on a random instance port; the public gateway stays fixed.
server = dcc_mcp_3dsmax.start_server()

# Progressive loading — discover skills without loading them immediately
n = server.discover_skills()        # scan paths, register tool metadata
server.load_skill("3dsmax-scene")  # lazy-load a specific skill

dcc_mcp_3dsmax.stop_server()

Sidecar Bridge

Start the sidecar bootstrap inside 3ds Max:

python.ExecuteFile @"C:\path\to\dcc-mcp-3dsmax\examples\start_sidecar_bridge.py"

This starts the random-port /dispatch bridge for main-thread scene edits, a random-port qtserver:// bridge for the sidecar process, and registers the 3ds Max instance with the stable gateway at http://127.0.0.1:9765/mcp. See docs/SIDECAR.md.

The bootstrap also installs a DCC MCP menu with Start Sidecar, Stop Sidecar, Open Gateway Admin, and Print Status commands. 3ds Max shutdown triggers the same stop path via #preSystemShutdown, so the sidecar process and local bridges are cleaned up when the host exits.

Skill Development

Create a skill with SKILL.md metadata file and Python scripts:

# my_skill/action_create_box.py
from dcc_mcp_3dsmax.api import max_success, with_max

@with_max
def main(width: float = 100.0, height: float = 100.0, depth: float = 100.0) -> dict:
    import pymxs
    rt = pymxs.runtime

    box_obj = rt.Box(width=width, height=height, depth=depth)
    return max_success("Created box", object_name=str(box_obj))

Environment Variables

Variable	Description	Default
DCC_MCP_3DSMAX_METRICS	Enable Prometheus /metrics endpoint	0
DCC_MCP_3DSMAX_JOB_STORAGE	Path to SQLite job database	platform default
DCC_MCP_3DSMAX_DISABLE_EXECUTE_PYTHON	Disable execute_python tool	0
DCC_MCP_3DSMAX_DISABLE_ARBITRARY_SCRIPT	Disable all arbitrary script execution	0
DCC_MCP_3DSMAX_ENABLE_GATEWAY_FAILOVER	Enable gateway failover	1
DCC_MCP_3DSMAX_SKILL_PATHS	Extra skill search paths (semicolon-separated)	None
DCC_MCP_3DSMAX_BRIDGE_PORT	Sidecar bridge localhost port	random
DCC_MCP_3DSMAX_SIDECAR_LOG	Explicit stdout/stderr log file for the sidecar subprocess	platform log dir
DCC_MCP_3DSMAX_SIDECAR_LOG_DIR	Directory for default sidecar stdout/stderr logs	core log dir
DCC_MCP_3DSMAX_SIDECAR_LOG_RETENTION_DAYS	Days to keep default sidecar logs	14
DCC_MCP_3DSMAX_SIDECAR_LOG_MAX_BYTES	Rotate a default sidecar log after this size	10485760
DCC_MCP_3DSMAX_SIDECAR_LOG_MAX_FILES	Rotated default sidecar log files to keep	5
DCC_MCP_3DSMAX_BOOTSTRAP_PATHS	Extra package Python roots for startup bootstrapping	None
DCC_MCP_PYTHONPATHS	Shared package Python roots for Rez/pipeline launchers	None
DCC_MCP_3DSMAX_ROOT	Adapter package root; startup probes python, python37, src, and root	None
DCC_MCP_CORE_ROOT	dcc-mcp-core package root; startup probes python, python37, src, and root	None
DCC_MCP_SERVER_ROOT	dcc-mcp-server package root; startup probes Python roots and sidecar binary locations	None
DCC_MCP_SERVER_BIN	Explicit dcc-mcp-server executable path	auto-detect
DCC_MCP_REGISTRY_DIR	Optional shared gateway/sidecar registry override	core default

For Rez-style deployment, launch 3ds Max with package roots in the environment instead of copying packages into the user scripts folder. A pipeline package cache can expose paths such as <package-cache>/dcc_mcp_core, <package-cache>/dcc_mcp_3dsmax, and <package-cache>/dcc_mcp_server through the root variables above. The MZP installer uses isolated version directories under <user scripts>/dcc_mcp_3dsmax/versions/, so installing a new payload does not delete the version that may already be loaded by the running 3ds Max process. Uninstall cleanup uses the import-light lifecycle helpers from dcc-mcp-core when available, so locked native files are reported as restart-required instead of disappearing into a generic PermissionError.

Requirements

• 3ds Max 2017 or later (Python 3.x with pymxs support)
• Python >= 3.7
• dcc-mcp-core >= 0.17.23
• dcc-mcp-server >= 0.17.23

License

MIT