maguro-tsukiji/blend-studio is an MCP Apps plugin that displays .blend, .glb, and .vrm files locally, and conveys edit locations to the chat side through numbered markers placed on the model surface. The 2026-10-16 (UTC) commit 972c83a raises the version of this repository from 0.1.13 to 0.1.14, and contains work that leaves a record, in the lighting determination, that the Blender VRM Add-on's MToon 1.0 materials were originally MToon even in the converted preview. The commit is on the scale of 131 lines added and 21 lines removed, and its contents are summarized in the 0.1.14 entry of the CHANGELOG (dated 2026-10-17).
The problem was that when the MToon shader is approximated to PBR at the conversion stage, the viewer sees only that result, wrongly chooses strong PBR default lighting, and bright-colored details are lost. This change makes the .blend converter find the VRM Add-on MToon 1.0 output node and its Principled-compatible output, attach blendStudioSourceShader: MToon to the material extras of the preview GLB, and the lighting selection in Original mode also uses this hint. The screen displays the actual rendering method and the pre-conversion method separately, and MToon-converted materials are labeled as PBR (MToon conversion). When replacing the file in the same tab, manually adjusted lighting is retained, and a new tab opens with the model defaults.
However, the shader that is actually rendered is still a PBR approximation, and it does not claim to preserve the original shader as-is. The lighting and materials of the original file are not touched. The README states that 0.1.14 is also at an experimental stage, that only display and edit-location sharing are implemented, and that Blender live editing and Tripo generation are not yet connected. Regression verification was added as a procedure that sets TEST_BLENDER_PATH and BLENDER_PATH in an environment with Blender and runs tests/blend-lighting.test.mjs; it covers the original fixtures, the conversion and GLTFLoader paths, plain PBR, and unconnected MToon nodes, but no metric comparing screen quality is presented.