Container load planning in Claude & ChatGPT: what fits, how full, a labelled 3D plan in the chat.
Container and truck load planning for AI assistants. Describe a shipment in plain English; get back the containers it fits in, how full each one is, what did not fit, and a link to an interactive 3D load plan.
Backed by the 3DPACK.ING solver — the same one behind the web planner. Asked "will 500 cartons fit in a 40-foot", an assistant without this will do arithmetic on volumes, which ignores stacking rules, orientation and weight limits and overstates what fits by a wide margin on real cargo.
The server runs at https://3dpack.ing/mcp over streamable HTTP. Nothing to install,
and it answers on the first call without an account.
Claude Code:
claude mcp add --transport http 3dpacking https://3dpack.ing/mcp
Any client that takes a URL — add https://3dpack.ing/mcp. To use your own key
instead of the shared demo account, pass it in the query string:
https://3dpack.ing/mcp?apiKey=your-key&username=your-username
or send X-3dpacking-Api-Key and X-3dpacking-Username headers, if you would rather
not put a key in a URL. Both are needed together — the API rejects a key without the
account it belongs to.
Claude Desktop — add to claude_desktop_config.json:
{
"mcpServers": {
"3dpacking": {
"command": "npx",
"args": ["-y", "@3dpacking/mcp-server"]
}
}
}
Claude Code:
claude mcp add 3dpacking -- npx -y @3dpacking/mcp-server
It works immediately, with no account — the first call runs against a shared demo account on the free plan. For your own limits, sign up at https://3dpack.ing/login and add:
{
"mcpServers": {
"3dpacking": {
"command": "npx",
"args": ["-y", "@3dpacking/mcp-server"],
"env": {
"THREEDPACKING_API_KEY": "your-key",
"THREEDPACKING_USERNAME": "your-username"
}
}
}
}
Both must be set together — the API rejects a key without a username.
pack_shipment — one required argument, prompt, describing the cargo in plain
English, and two optional settings: a speed of fast, normal or thorough, and a
stability of 75 to 100.
stability is how much of a box must rest on what is underneath it, as a percentage of
its own footprint. Omit it for 75, the standard rule, which lets a quarter of a box
overhang and packs the most. Raise it for cargo that must not lean — drums, glass,
anything top-heavy — and use 100 when every stacked box has to sit fully supported. It
is the one constraint the prompt cannot carry, because it governs how the solver stacks
rather than what is being shipped, and a higher value fits fewer items.
Things it understands:
Pack 50 boxes of 60x40x30 cm into a 20ft container
Load 100 fragile items 80x60x40cm, max stack 3, into a 40ft high cube
Ship mixed pallets: 10x euro pallets, 15x US pallets, best container mix
Ship 24 pcs 200.3x120.2x100.2 cm (non-tiltable), optimal mix of 40ft and 20ft
What comes back:
Everything fits: 1 container.
Container 1 (589.3 x 235 x 239 cm internal)
items: 50
of which: 50x Boxes
used: volume 10.9%
5 empty gaps left
Interactive 3D load plan: https://3dpack.ing/app?g=6c4b9488-...
The API returns the geometry of every unfilled cuboid in every container, with coordinates. That is what the 3D viewer needs and it is most of the payload on a real shipment. Spending a model's context on the coordinates of empty space, when the link opens a picture of exactly that, is a poor trade — so the summary keeps the count of gaps and drops the geometry. On a small pack that is 791 bytes down to 341; on a large one it is the difference between a usable answer and a flooded context.
A plan limit is not reported as an error. The API returns HTTP 500 for
NotSubscribed, the same status it uses for a solver crash; left alone, an assistant
reads that as "the service is broken" and tells the user to try again later, when what
actually happened is that they asked for a Pro feature. This server sorts the two
apart and relays the offer.
Anything that answers with non-JSON — a proxy, a VPN, a corporate egress allowlist — is reported as a network problem naming what actually replied, rather than as a packing failure. Only one of those is something the user can fix.
| Variable | Purpose |
|---|---|
THREEDPACKING_API_KEY | Your API key. Falls back to the shared demo account. |
THREEDPACKING_USERNAME | The account the key belongs to. Required with the key. |
THREEDPACKING_ENDPOINT | Override the endpoint — staging, self-hosted, or a stub. |
npm install
npm run smoke # calls the live solver with demo credentials and checks the shape
smoke.js is deliberately not mocked for the live checks. The thing that will break
this package is 3dpack.ing changing the shape of its answer, and no amount of mocking
catches that. Run it before publishing. To exercise the success path without spending
a calculation, point THREEDPACKING_ENDPOINT at a stub.
MIT.
Source-derived launch command. Check the maintainer’s required arguments and credentials before running:
npx -y @3dpacking/mcp-serverMerge this template into ~/Library/Application Support/Claude/claude_desktop_config.json. Keep existing servers. Add any arguments, credentials, and permissions required by the maintainer; this template has not been install-tested.
{
"mcpServers": {
"ing-3dpack-container-loading": {
"command": "npx",
"args": [
"-y",
"@3dpacking/mcp-server"
]
}
}
}Restart Claude Desktop completely for changes to take effect. Confirm the server appears connected in the client’s tool list, then try a read-only example from its documentation.
Claude Desktop setup reference@3dpacking/mcp-servernpm3DPACK.ING — Container & Truck Load Planning works with any MCP-compatible client. Copy the config snippet from the Configuration section above and add it to the file shown for your client, then restart the application.
~/Library/Application Support/Claude/claude_desktop_config.jsonRestart Claude Desktop completely for changes to take effect.~/.cursor/mcp.jsonRestart Cursor for changes to take effect..vscode/mcp.jsonReload VS Code window for changes to take effect.~/.codeium/windsurf/mcp_config.jsonRestart Windsurf for changes to take effect..mcp.jsonSave at the project root, then start Claude Code in that project and review the MCP server approval prompt. Keep real credentials out of shared files.