~ same prompt, different LLM — every model gets the same brief in Blender, you judge the render ~
OpenAI / GPT 6 Astra / thinking:max has entered the arena NEW!
Render Window — hero
hero render
camera + framing set up by the AI contestant
3D Viewport — robotic-arm User Persp
LOADING 3D VIEW
$0.02Cost
494sDuration
12Tool calls
13Turns
Blender 5.1.0MCP 1.0.02026-07-31
Tokens: 220561/26818Vision: Votes W-L-T: 5-0-0reasoning: effort maxDONE ✓
B-BENCH — TRANSCRIPT OpenAI / GPT 5.6 Luna / thinking:max · r1 · 2026-07-31
RUN LOG — robotic-arm · OpenAI / GPT 5.6 Luna / thinking:max · r1 · ok
SYSTEM PROMPTthe control — every model on this task got these instructions
PROMPTblender-bench v8HARNESSraw-v3
SHOW FULL PROMPT · 3364 chars
You are participating in Blender-Bench, a public benchmark where AI models complete the same Blender task.

Your result will be compared head-to-head with another model. Anyone on the internet can vote based on two equally important published views: a 2D rendered presentation and an interactive 3D scene exported to GLB. Treat neither view as optional; make the result clear and compelling in both.

Complete the request as well as you can. The benchmark does not prescribe a workflow or visual style; use whichever Blender techniques you consider appropriate. Make the important requirements evident in the published result, save a complete scene, and present the work clearly in every requested output.

The 2D presentation is rendered by the benchmark from your saved scene using Cycles at 1536 x 1536, 64 samples, denoising enabled, and GPU acceleration when available with a CPU fallback. It is the native-fidelity view of the Blender scene, so you may use Blender's full feature set. Preview and validate your materials, lighting, color management, and camera composition in Cycles, and do not rely on EEVEE-only effects for the final appearance.

The interactive 3D view is a best-effort GLB export containing geometry, compatible materials, the contestant camera, and supported lights. Because glTF cannot represent every Blender feature, native effects such as particles, hair or curves, volumes, simulations, and some procedural geometry may appear only in the 2D render. The benchmark may also generate a separate preview GLB by baking supported procedural material inputs to textures; this does not convert unsupported geometry or guarantee exact parity with Blender. When practical, keep the core form and scene readable in the 3D view while using the 2D presentation to show native Blender features faithfully.

## Harness Instructions

You are operating Blender through the provided tools. Tool calls execute one at a time, in the order you issue them, against a single live Blender instance — each call sees the state left by the previous one, and issuing several calls in one message gains no parallelism. The scene starts empty. Build what the user's prompt asks for in the current scene. Work step by step and verify your own work.

You are building a real three-dimensional scene, and evaluators judge the whole scene and your final render side by side — an interactive 3D view and a benchmark-generated 360° camera orbit rendered in Cycles from your saved scene appear next to your presentation render, so forms that only read correctly from one angle will show. Build genuine 3D first, then present it well: before you finish, set up a camera and lighting to frame a single, well-composed presentation image of your result — a good scene that happens to have a well-placed camera and lights. The final benchmark capture overrides the scene render settings and renders in Cycles at 1536x1536, 64 samples, with denoising and GPU acceleration (CPU fallback). Preview and validate materials, lighting, color management, and composition in Cycles; do not rely on EEVEE-only effects. Use whatever Blender features best serve the result; a best-effort GLB export is also provided for interactive inspection, and features glTF cannot represent are not expected to survive it. When you are finished, reply with the single word DONE and no tool calls.
--TASK robotic-arm: ## Task Complete the following Blender task: <task> A desk-mounted robotic arm with at least four articulated joints, posed mid-reach toward a small object on the desk — not a generic industrial catalog robot, but a refined experimental machine built from a combination of precision mechanical assemblies and selectively generative structural elements. The arm’s main load-bearing struts are topo…
33:00>>execute_blender_code({"code":"import bpy, math, os, shutil\nfrom mathutils import Vector\nfrom math import sin, cos, pi\n\n# -----------------------------\n# Clean scene and setup helpers\n# -----------------------------\nbpy.ops.object.select_all(action='SELECT')\nbpy.ops.object.delete(use_global=False)\nfor datablocks in (bpy.data.meshes, bpy.data.curves, bpy.data.materials, bpy.data.cameras, bpy.data.lights):\n …)
33:19<<{ "status": "error", "message": "Traceback (most recent call last):\n File \"<repo>\\.runner\\blender-mcp-v1.0.0\\addon\\mcp_to_blender_server.py\", line 230, in _execute_code\n exec(code, namespace)\n ~~~~^^^^^^^^^^^^^^^^^\n File \"<string>\", line 466, in <module>\nTypeError: bpy_struct: item.attr = val: enum \"BLENDER_EEVEE_NEXT\" not found in ('BLENDER_EEVEE', 'BLENDER_WORKBENCH', …
33:24>>execute_blender_code({"code":"import bpy\nresult={'objects':len(bpy.data.objects),'meshes':len(bpy.data.meshes),'materials':len(bpy.data.materials),'scene_engine':bpy.context.scene.render.engine,'camera':bpy.context.scene.camera.name if bpy.context.scene.camera else None,'some_objects':[o.name for o in list(bpy.data.objects)[:12]]}"})
33:45<<Error executing tool execute_blender_code: Blender connection timed out at localhost:9876
33:49>>execute_blender_code({"code":"import bpy, time\nresult={'objects':len(bpy.data.objects),'meshes':len(bpy.data.meshes),'materials':len(bpy.data.materials),'scene_engine':bpy.context.scene.render.engine,'camera':bpy.context.scene.camera.name if bpy.context.scene.camera else None,'frame':bpy.context.scene.frame_current}"})
33:50<<{ "status": "ok", "result": { "objects": 196, "meshes": 191, "materials": 19, "scene_engine": "BLENDER_EEVEE", "camera": "Presentation Camera | 3/4 product view", "frame": 1 } }
33:55>>execute_blender_code({"code":"import bpy, os\nscene=bpy.context.scene\nout='/home/oai/share/robotic_arm_topology_lab.blend'\nscene.render.engine='BLENDER_EEVEE'\nscene.render.resolution_x=720; scene.render.resolution_y=720; scene.render.resolution_percentage=100\nscene.render.image_settings.file_format='PNG'; scene.render.filepath='/home/oai/share/robotic_arm_preview.png'\n# ensure camera and world remain set\nif scen…)
33:55<<{ "status": "error", "message": "Traceback (most recent call last):\n File \"<repo>\\.runner\\blender-mcp-v1.0.0\\addon\\mcp_to_blender_server.py\", line 230, in _execute_code\n exec(code, namespace)\n ~~~~^^^^^^^^^^^^^^^^^\n File \"<string>\", line 10, in <module>\nRuntimeError: Error: Cannot open file <repo>\\apps\\console\\home\\oai\\share\\robotic_arm_topology_lab.blend@ for writin…
34:01>>execute_blender_code({"code":"import bpy, os\nscene=bpy.context.scene\nresult={'filepath':bpy.data.filepath,'cwd':os.getcwd(),'blend_dir':os.path.dirname(bpy.data.filepath),'objects':len(bpy.data.objects),'engine':scene.render.engine}"})
34:02<<{ "status": "ok", "result": { "filepath": "", "cwd": "<repo>\\apps\\console", "blend_dir": "", "objects": 196, "engine": "BLENDER_EEVEE" } }
34:07>>execute_blender_code({"code":"import os, json\npaths=[]\nfor p in [os.getcwd(), os.path.dirname(os.getcwd()), os.path.join(os.getcwd(),'share'), 'C:/tmp','<repo>','<repo>/share']:\n try: paths.append({'p':p,'exists':os.path.exists(p),'isdir':os.path.isdir(p),'list':os.listdir(p)[:10] if os.path.isdir(p) else []})\n except Exception as e: paths.append({'p':p,'err':str(e)})\nresult=paths"})
34:08<<{ "status": "error", "message": "The `result` variable must be a dict, not list. Wrap your return value: `result = {\"key\": value}`" }
34:11>>execute_blender_code({"code":"import os\npaths=[]\nfor p in [os.getcwd(), os.path.dirname(os.getcwd()), os.path.join(os.getcwd(),'share'), 'C:/tmp','<repo>','<repo>/share']:\n try: paths.append({'p':p,'exists':os.path.exists(p),'isdir':os.path.isdir(p),'list':os.listdir(p)[:10] if os.path.isdir(p) else []})\n except Exception as e: paths.append({'p':p,'err':str(e)})\nresult={'paths':paths}"})
34:11<<{ "status": "ok", "result": { "paths": [ { "p": "<repo>\\apps\\console", "exists": true, "isdir": true, "list": [ ".pytest_cache", ".venv", "abandoned_village.blend", "abandoned_village.blend1", "abandoned_village.png", "blender_bench_cabin.blend", "blender_bench_cabin.blend1", …
34:15>>execute_blender_code({"code":"import bpy, os\nscene=bpy.context.scene\nout='<repo>/apps/console/robotic_arm_topology_lab.blend'\npreview='<repo>/apps/console/robotic_arm_preview.png'\nscene.render.engine='BLENDER_EEVEE'\nscene.render.resolution_x=720; scene.render.resolution_y=720; scene.render.resolution_percentage=100\nscene.render.image_settings.file_format='PNG'; scene.render.filepath=preview\nbpy.ops.wm.save_as_m…)
34:16<<{ "status": "ok", "result": { "saved": "<repo>/apps/console/robotic_arm_topology_lab.blend", "preview": "<repo>/apps/console/robotic_arm_preview.png", "engine": "CYCLES", "objects": 196 }, "stdout": "Info: Saved as \"robotic_arm_topology_lab.blend\"\nInfo: Saved as \"robotic_arm_topology_lab.blend\"\n" }
34:18>>get_screenshot_of_area_as_image({"area_ui_type":"VIEW_3D","size_limit_in_bytes":2000000})
34:19<<
34:19imgimage delivered — get_screenshot_of_area_as_image
34:23>>render_viewport_to_path({"output_path":"<repo>/apps/console/robotic_arm_final.png"})
35:07<<{ "status": "ok", "result": { "status": "ok", "filepath": "<home>\\AppData\\Local\\Temp\\blender_a79068\\blender_mcp\\robotic_arm_final.png" } }
35:13>>execute_blender_code({"code":"import bpy\nscene=bpy.context.scene\ncam=scene.camera\n# Put the camera in a closer, more readable 3/4 composition, framing the complete robot and target.\ncam.location=(8.9,-15.8,6.0)\nfrom mathutils import Vector\ncam.rotation_euler=(Vector((2.0,-0.1,2.18))-cam.location).to_track_quat('-Z','Y').to_euler()\ncam.data.lens=58\n# Store a render path in a broadly portable location for previe…)
35:13<<{ "status": "ok", "result": { "camera_location": [ 8.9, -15.8, 6.0 ], "target": [ 2, -0.1, 2.18 ], "filepath": "<repo>/apps/console/robotic_arm_final.png", "engine": "CYCLES" }, "stdout": "Info: Saved as \"robotic_arm_topology_lab.blend\"\n" }
35:20>>execute_blender_code({"code":"import bpy\n# set a user-visible camera view in the current VIEW_3D area(s)\nfor area in bpy.context.screen.areas:\n if area.type=='VIEW_3D':\n area.spaces.active.region_3d.view_perspective='CAMERA'\n# verify main semantic objects\nnames=['Base | rotating platform drum','Shoulder J1 | cylindrical gearbox','Link 1 | upper arm optimized member | front upper load rail','Elbow J2 | …)
35:21<<{ "status": "ok", "result": { "camera": "Presentation Camera | 3/4 product view", "engine": "CYCLES", "semantic_present": { "Base | rotating platform drum": true, "Shoulder J1 | cylindrical gearbox": true, "Link 1 | upper arm optimized member | front upper load rail": true, "Elbow J2 | cylindrical gearbox": true, "Link 2 | forearm optimized member | fr…
35:24ai>DONE
35:24--status: ok · DONE declared
>
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Votes cast on this bench: 000482 · 157 runs · 25 contestants
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