dsh-fusion360
从 DeepSeek Harness 驱动 Autodesk Fusion 360：包含一个 Fusion 360 插件和一个无依赖的 MCP 服务器，提供 13 个 mcp__fusion360__* 工具。安装中的 DSH 端是下方声明的 cordis 补丁；另一端是 Fusion 插件，npm 无法安装。请参阅仓库 README。
插件会安装到这里；不确定时保持 web。
npx -y @deepseek-ai/dsh plugin --profile web add github:Leaveing00001/dsh-fusion360#c4f0fdaf36291a64a752c4e33a44f40f20ab3003Fusion360 以 dsh-fusion360 发布，当前版本为 1.0.3。Plugin Hub 会校验它的 manifest，并保存精确安装来源，便于复现安装结果。
Drive Autodesk Fusion 360 from DeepSeek Harness. Query the model, change parameters, export files, and run arbitrary Fusion API Python — from a chat.
中文说明 · Install · Verification · Fusion API notes · DSH compatibility
🐋 This is a DeepSeek Harness VibeCoding artifact
This project was vibe-coded end to end by DeepSeek Harness (DSH). Nobody wrote it by hand and then handed it to an agent to tidy up: the agent built it in conversation, driving a live Fusion 360 through the very bridge it was still writing.
Concretely, the agent:
- read DSH's own installed application tree and Fusion's shipped Python type stubs to learn the two APIs instead of trusting its memory of them;
- wrote the Fusion add-in, the MCP server, and three test harnesses;
- installed the add-in into Fusion, restarted DSH, and then called its own tools back through the MCP layer;
- drove 15 modelling commands against real Fusion and checked each result against its closed-form volume, rather than settling for "the call did not raise" — see the measured table;
- hit 17 places where its recall of the Fusion API disagreed with reality, and corrected every one from the actual error text. Those are written up in Fusion API notes.
The mistakes are documented rather than hidden, because they are the useful part: most of them fail silently in Fusion's API — a chamfer that produces a healthy feature and changes nothing, a sketch that quietly absorbs a circle as a hole. If you are writing Fusion API code yourself, that page will save you a day.
The prose in this README is the agent's too. Every number in it is a measurement the agent took on this machine, not a claim copied from a doc.
Fusion 360 has no headless mode. Any modelling operation needs a running Fusion instance, and the Fusion API is single-threaded — it may only be called from Fusion's primary thread. So a plain MCP server that shells out to Python cannot work. This is a two-part bridge:
┌─────────────┐ MCP over stdio ┌──────────────────┐ JSON over ┌────────────────────┐
│ DSH │ ──────────────────► │ MCP server │ ── loopback ──► │ Fusion 360 │
│ (dsh-mcp- │ newline JSON │ (this repo, │ TCP :27182 │ add-in │
│ client) │ ◄────────────────── │ stdlib only) │ ◄───────────── │ (primary thread) │
└─────────────┘ └──────────────────┘ └────────────────────┘
The MCP server runs as an ordinary DSH-spawned subprocess. The add-in runs
inside Fusion, joins the socket requests back onto Fusion's primary thread with
a CustomEvent, and executes them there.
| Fusion 360 | A desktop install that can run add-ins — verified on 2705.1.15. Fusion has no headless mode, so nothing here works without the app running. |
| DSH Desktop | Verified on 2.0.17 (2.0.9 also worked). See DSH compatibility. |
| Python | 3.8+ for the MCP server. Standard library only — no mcp wheel, no pip install. |
| OS | Windows, verified. The bridge itself is plain stdlib and the manifest declares windows|mac, but nothing here has been run on macOS. The helpers in tools/ are PowerShell and .bat, so those are Windows-only. |
# 1. Install the add-in into Fusion's own AddIns folder (enables runOnStartup)
powershell -ExecutionPolicy Bypass -File tools\install_addin.ps1
# 2. Register the MCP server with DSH - fills in every path for you
python tools\install_dsh_mcp.py
# 3. Restart DSH - a new profile row is NOT hot-loaded
python tools\restart_dsh.py
# 4. Start Fusion 360, then verify
The install is two-part and
npmcannot complete it.package.jsondeclaresdsh.bundle.patch— the DSH-side half, which is the cordis patch indsh/cordis.patch.yml— but the other half is an add-in that has to be copied into Fusion's AddIns folder, which no package manager can do for you. There is deliberately nopostinstallscript reaching into another application's directories; the two commands above are the install. The npm manifest exists so plugin catalogs can identify this repo, which is why it is marked"private": trueand not published.
Ask DSH to call mcp__fusion360__fusion_status. A healthy reply:
{
"bridge": "FusionDSHBridge",
"bridgeVersion": "1.0.3",
"fusionVersion": "2705.1.15",
"user": "you@example.com",
"host": "127.0.0.1",
"port": 27182
}
Full walkthrough, including the manual add-in path and troubleshooting: docs/install.md.
examples/build_a_part.py builds a 100 × 60 × 8 mm
plate with four R6 corner rounds and four ⌀4.5 through holes, and checks its own
volume at every stage — 48000 → 47752.78 → 47243.84 mm³. Run it as the code
argument of mcp__fusion360__fusion_run_python and it either matches or raises.
It is the fastest way to tell a working install from a broken one, and it is
worth reading as an example of the API's sharp edges being handled: profile
selection by bounding box, the sketch-frame conversion, and the chamfer's
isTangentChain trap are all commented in place.
Thirteen tools, exposed to DSH as mcp__fusion360__<name>.
| Tool | Purpose |
|---|---|
fusion_status | Reachability, Fusion version, signed-in user |
fusion_document_info | Active design: units, body/parameter counts, bounding box |
fusion_list_bodies | Every body with volume (mm³), area (mm²), bbox, material |
fusion_list_parameters | All model and user parameters |
fusion_set_parameter | Set an expression and recompute — the parametric path |
fusion_create_document | New empty design |
fusion_list_documents | Open documents |
fusion_open_document | Open a cloud data file by name |
fusion_save | Save the active document |
fusion_export | Export to STEP/IGES/STL/OBJ/F3D/SMT/SAT |
fusion_text_command | Raw Fusion text command |
fusion_reload_bridge | Re-execute the add-in from disk and restart its listener |
fusion_run_python | Arbitrary Python on Fusion's primary thread |
fusion_run_python is the escape hatch that makes the set complete: anything
Fusion's API can do, you can do. adsk, app, ui, design and root come
pre-bound, stdout is captured, and assigning to result returns a value.
sketch = root.sketches.add(root.xYConstructionPlane)
sketch.sketchCurves.sketchCircles.addByCenterRadius(
adsk.core.Point3D.create(0, 0, 0), 2.0) # centimetres
extrude = root.features.extrudeFeatures
inp = extrude.createInput(
sketch.profiles.item(0), adsk.fusion.FeatureOperations.NewBodyFeatureOperation)
inp.setDistanceExtent(False, adsk.core.ValueInput.createByReal(1.0))
extrude.add(inp)
result = {'bodies': root.bRepBodies.count}
Units: the Fusion API works in centimetres and radians regardless of the document's display units. The read-only tools convert to millimetres for you; code passed to
fusion_run_pythondoes not get that treatment.
Every command below was driven through fusion_run_python against a live Fusion
2705.1.15 and checked against the closed-form volume. These are measurements,
not smoke tests.
| Command | Measured | Analytic |
|---|---|---|
| Sketch: rectangle, circle, arc, fitted spline | 8 curves, 3 closed profiles | — |
| Extrude, new body 60 × 40 × 10 | 24000.00 mm³ | 24000 |
| Extrude, join — boss ⌀16 × 16 | +3216.99 mm³ | +3216.99 |
| Extrude, cut through-all — ⌀10 | −785.40 mm³ | −785.40 |
| Fillet, 4 vertical edges R3 | −77.26 mm³ | −77.26 |
| Chamfer, 4 top edges 1 mm | −98.67 mm³, 6 → 10 faces | −100 |
| Loft, ⌀40 → ⌀16 over 30 mm | 19603.54 mm³ | 19603.54 |
| Revolve, rectangle about Z, 360° | 42411.50 mm³ | 42411.50 |
| Sweep, ⌀10 circle along a 50 mm line | 3926.99 mm³ | 3926.99 |
| Shell, top face open, 2 mm wall | 7872.00 mm³ | 7872 |
| Hole ⌀4.5 through 8 mm | −127.23 mm³ | −127.23 |
| Rectangular pattern 2 × 2 | 47491.06 mm³, 4 holes | 47491.06 |
| Full part: plate + R6 + 4 × ⌀4.5 | 48000.00 → 47752.78 → 47243.84 | same |
| Sketch on a solid face + blind cut | 23547.61 mm³ | 23547.61 |
The chamfer's shortfall against a naive area × length figure is the corner
treatment where four chamfers meet — it reproduces on a plain box (98.667 vs
100 mm³), so it is geometry, not error.
Full tables, including the MCP-layer round trip and the STL/STEP export checks: docs/verification.md.
Fusion renames and removes API members between releases, and the failures are silent. Four that cost real time here:
Sketches.add(face) silently injects the face outline as ordinary sketch
lines. profiles.item(0) on a sketch made on a plate's top face is the plate,
not the circle you just drew. Select profiles by boundingBox, never by index.isTangentChain=True. With False the
feature is created, healthState is healthy, errorOrWarningMessage is empty,
and nothing changes.Face.geometry.normal does not tell top from bottom. Both planar faces of
a plate can report +Z — it describes the underlying surface, not the face.All seventeen are in docs/fusion-api-notes.md, each with the error text it produces and the fix.
| Path | Role |
|---|---|
fusion_addin/ | The add-in that runs inside Fusion 360 |
mcp_server/fusion_mcp_server.py | MCP server DSH spawns; standard library only |
dsh/cordis.patch.yml | The profile patch entry that registers it with DSH |
package.json | Declares dsh.bundle.patch and names this repo's DSH-side artifact |
docs/ | Install guide, measurements, Fusion API notes, DSH compatibility |
examples/ | A commented part build you can run as-is |
tools/ | Tests, probes, installer, DSH restart helper |
# Full MCP exchange against the fake bridge - no Fusion, no subprocesses
python tools\smoke_test.py
# Add-in worker -> primary thread hand-off, against a stubbed adsk package
python tools\addin_stub_test.py
# Against a live Fusion: builds real geometry, reads it back, exports it
python tools\verify_e2e.py
# Protocol handshake only
python mcp_server\fusion_mcp_server.py --selftest
# Talk to the bridge directly (bypasses DSH entirely)
python tools\probe_bridge.py --cmd ping
# Re-install the add-in after editing it
powershell -ExecutionPolicy Bypass -File tools\install_addin.ps1
--args-file exists on probe_bridge.py because both PowerShell and cmd mangle
inline JSON quotes when passing arguments to a native executable.
A code change normally needs a human to click Stop then Run in the Scripts
and Add-Ins dialog. fusion_reload_bridge (or probe_bridge.py --cmd reload)
re-executes the add-in from disk and rebinds its listener instead, so iteration
needs no GUI at all. The listener drops for about a second; poll until ping
reports the new bridgeVersion.
If a self-reload fails the listener is gone and only the GUI can bring it back, so keep the manual path as the recovery route.
Port — edit fusion_addin/bridge_config.json and the matching
FUSION_DSH_BRIDGE_PORT in dsh/cordis.patch.yml. Default 27182.
Security — the endpoint binds 127.0.0.1 only, so it is not reachable from
the network. It is still an unauthenticated local RPC that can execute Python
inside Fusion; treat access to this machine's loopback as the trust boundary.
Do not expose the port.
Log — the add-in appends to fusion_addin/bridge.log and also writes to
Fusion's own log via app.log(). Check it first when the add-in will not start.
pip install is needed and the interpreter can be any
Python 3.8+.mcp__fusion360__<tool>, so
renaming a tool would break session history — treat the names as frozen.failOnStartupError: false keeps DSH booting when Fusion is closed. The
tools appear regardless and report the bridge as unreachable.MIT — see LICENSE.
Fusion 360 and Autodesk are trademarks of Autodesk, Inc. This project is not affiliated with or endorsed by Autodesk.