Blender Bridge

Connect Profy to the Blender instance running on your own machine, so an expert can inspect the scene graph, execute Python (bpy), capture viewport screenshots to verify its own work, and export GLB. This is orthogonal to Profy’s cloud 3D capabilities. profy-visualize and profy-game-studio build web-runnable 3D with Three.js inside the sandbox. Blender Bridge operates on the actual .blend file sitting on your desktop.

Current implementation status (verified 2026-08-11): this plugin’s mcpServers declaration (uvx blender-mcp) has no consumer anywhere in the codebase. The PluginManifest.mcp_servers field in agent-runtime is parsed but never read, and Core’s MCP assembly path (buildCommunityMcpToolsAndConfig) only handles community plugin installations — it does not cover built-in manifests.In practice: ticking this plugin gives you its skill and prompt layer (the workflow discipline, safety rules, and export parameters below do take effect and shape model behaviour), but it does not give you callable Blender tools. Treat it as “a methodology for working with Blender” rather than “a remote control”, until the wiring is completed.

Declaration and activation

{
  "id": "blender-bridge",
  "name": "Blender Bridge",
  "version": "1.0.0",
  "mcpServers": [{ "name": "blender", "command": "uvx", "args": ["blender-mcp"] }],
  "activation": { "requires": { "desktop_connected": true }, "user_selectable": true }
}

Two independent gates must both pass before the manifest contributes anything:

Gate	Condition	If unmet
`user_selectable: true`	The plugin ID must appear in the set selected for this conversation	The whole manifest is skipped
`requires.desktop_connected: true`	Runtime `desktop_connected` is true, which is derived from the `PROFY_DESKTOP` environment variable equalling `"true"`	The whole manifest is skipped

The evaluation order is: selectable gate first, then every entry in requires (booleans compared by truthiness, lists by membership, strings by equality), then legacy conditions. Any failure short-circuits. The second gate means this plugin exists only inside Profy Desktop. A browser conversation in the cloud cannot select it and cannot activate it — the Blender you want to drive lives on your machine, and a cloud sandbox has no route to it.

Prerequisites

Requirement	Notes
Blender 4.x or newer	Must be running; this is not passive file parsing
BlenderMCP addon enabled	It is what exposes the MCP endpoint inside Blender
Python `uv` installed	`uvx` is used to launch `blender-mcp`
Profy Desktop	Not available in the cloud, per the activation gate above

marketplace.installMode is ON_INSTALL, meaning setup happens at install time rather than lazily on first call. marketplace.availability is AVAILABLE and the category is creative-tools.

Workflow discipline (skill layer, active today)

The bundled blender-workflow skill defines the cadence the model follows. The core idea is look after every step:

Inspect the current scene → understand what already exists
Break the change into small steps
Execute one operation at a time
Screenshot the viewport after each change → verify visually
If wrong, undo and retry
When satisfied, save and optionally export

Vision in the loop

The skill encodes one non-negotiable rule: screenshot after every single modelling operation, then ask whether the shape is right, the position is right, and the materials applied. Fix problems before moving on.

Never assume an operation succeeded — always verify visually.

This discipline does not depend on the MCP wiring. It constrains how the model self-verifies in any 3D task, which is why the skill layer is worth having even while the tool layer is incomplete.

Pre-flight checklist

Verify the MCP connection by calling any Blender tool, e.g. get_scene_info
Confirm the Blender version (4.x+) and the addon status
Identify the current scene state before making any changes

Step 3 exists because “create a cube” means something different in an empty scene versus a scene that already has forty objects and a specific naming convention.

Capability inventory (available once MCP is wired)

Category	Contents
Scene inspection	Object list, transforms, materials, lights
Object creation	Mesh primitives, curves, empties
Modelling	Modifiers: subdivision, boolean, array, mirror
Materials	PBR metalness–roughness workflow (base colour / metalness / roughness / normal)
Lighting	HDRI environment, area / point / spot lights
Scripting	Execute arbitrary `bpy` Python
Export	GLB / FBX / OBJ
Asset libraries	Poly Haven (HDRI, textures, models), Hyper3D Rodin

Web export parameters

Models destined for the web have specific parameters, not “just export it”:

Item	Value	Why
Format	GLB (binary glTF)	Single file, natively supported by browsers
Compression	Draco enabled	Substantially reduces geometry size
Textures	Embedded, max 2048×2048	Beyond this, mobile pays more than it gains
Transforms	Apply before export	Otherwise downstream consumers receive wrong transforms
Verification	Open in a Three.js viewer after export	”Export succeeded” is not “loads correctly”

The full pipeline is: model in Blender → optimise (decimate, bake textures) → export GLB → load in Profy’s visualize or game-studio → deploy via Sites.

Safety rules

Four hard constraints from the skill that the model will honour:

Never overwrite without asking — use “Save As” for new versions
Never delete objects without confirmation
Never modify files outside the project directory
Always work on a copy, never the original

These are worth reading as a statement of intent. An agent with bpy execution has, in principle, arbitrary file access through Python; the skill narrows that voluntarily. It is discipline, not a sandbox — if you need a hard boundary, keep the original file outside the project directory entirely.

Boundaries and failure modes

No Desktop, no plugin. It does not appear in the plugin panel in cloud conversations. That is the activation gate working, not a bug.
Blender not running means pre-flight fails. The skill requires an initial scene-inspection call to confirm connectivity. On failure the model should stop and report, not carry on pretending to model.
The MCP declaration is currently unwired (see the warning at the top), so “the model says it should screenshot but has no screenshot tool” is expected behaviour right now, not the model being lazy.
Polygon budget is on you. Web export has no automatic decimation fallback. An over-budget model still exports fine; it just loads badly.
uvx downloads on first use. If your machine has no network route to PyPI, launching the server will fail regardless of Blender’s state.

Troubleshooting

Symptom	Cause	Fix
Blender Bridge missing from the plugin panel	Not in Desktop, or Desktop not connected	Open Profy Desktop and confirm the connection status
Selected, but the model says it has no Blender tools	`mcpServers` is unwired (see top of page)	Expected today; the skill layer still applies
`uvx` not found	Python `uv` is not installed	Install `uv`, then confirm `uvx blender-mcp` runs manually
Exported GLB is empty in Three.js	Transforms not applied before export, or nothing was selected	Walk the export parameter table item by item
Viewport screenshot looks correct but the export does not	Modifiers not applied, or the export selection differs from the viewport	Apply modifiers, then re-export with an explicit selection

Verify your setup

Open a new conversation in Profy Desktop. Blender Bridge should appear in the plugin panel — if it does not, Desktop is not connected and nothing further will work.
Tick it and ask “what objects are in the current Blender scene?”. If you get methodology advice instead of actual scene data, you have hit the unwired state described at the top of this page.
Ask it to outline the steps for “export the selected object as a web-ready GLB”. A correct answer mentions Draco, the 2048 texture ceiling, and applying transforms — which confirms the skill layer really did load.

3D and visualization

Cloud-side visualize / game-studio / AI 3D generation

Godot Bridge

Sibling bridge: game engine plus deterministic playtesting

Verified 2026-08-11. Sources: services/agent-runtime/src/plugins/builtin/blender-bridge/plugin.json, skills/blender-workflow/SKILL.md, prompts/BLENDER.md, services/agent-runtime/src/plugins/registry.py (_check_activation), services/agent-runtime/src/plugins/utils/types.py.

Get Started

Core Concepts

Guides

Platform & Account

Deep Dive

Blender Bridge

Blender Bridge

Declaration and activation

Prerequisites

Workflow discipline (skill layer, active today)

Vision in the loop

Pre-flight checklist

Capability inventory (available once MCP is wired)

Web export parameters

Safety rules

Boundaries and failure modes

Troubleshooting

Verify your setup

3D and visualization

Godot Bridge

​Blender Bridge

​Declaration and activation

​Prerequisites

​Workflow discipline (skill layer, active today)

​Vision in the loop

​Pre-flight checklist

​Capability inventory (available once MCP is wired)

​Web export parameters

​Safety rules

​Boundaries and failure modes

​Troubleshooting

​Verify your setup

​Related

3D and visualization

Godot Bridge

Blender Bridge

Declaration and activation

Prerequisites

Workflow discipline (skill layer, active today)

Vision in the loop

Pre-flight checklist

Capability inventory (available once MCP is wired)

Web export parameters

Safety rules

Boundaries and failure modes

Troubleshooting

Verify your setup

Related