FL Studio MCP 1.2.0.dev2 — UI-first development candidate

Current matrix: dev2 acceptance and limits. Older dev1 reports are retained as history. Native/visual/OCR automatic grid measurement covers tested Piano Roll and Playlist layouts. This is not universal coordinate-free automation.

Security release gate remains open: tested dependencies have3 deduplicated known advisories; see security review. Local GUI/audio acceptance does not imply a clean security audit. Do not use as a production or public-network deployment.

Windows / Python 3.12 / FL Studio 26.1.5 build 5618. Based on rosasynthesiz/flstudio-mcp; MIT retained. Development preview, not universal desktop automation. No running MCP configuration/controller is replaced.

Core tested edits use actual GUI input. Prefer UIA where controls exist; self-drawn Piano Roll, Playlist, Sytrus and Mixer use screenshot-confirmed window-relative targets. FLP parsing and read-only bridge calls verify results, not perform musical edits.

Default mode hides legacy background music writers. Explicit FLSTUDIO_MCP_ENABLE_LEGACY_WRITES=1 exposes compatibility tools; never describe those writes as GUI actions.

See capabilities, real acceptance, workflow, profiles. GUI input receipts deliberately return verified=false: observe post-state, save and independently verify the musical target.

Isolated installation

py -3.12 -m venv .venv
.\.venv\Scripts\python.exe -m pip install --index-url https://pypi.org/simple -r requirements-system-tested.txt
.\.venv\Scripts\python.exe -m pip install --index-url https://pypi.org/simple --no-deps -e .
.\.venv\Scripts\python.exe -m pip check
.\.venv\Scripts\python.exe -m pytest tests/test_ui_first.py -q

Full inherited regression explicitly exercises legacy writers against unit fakes, not real FL:

$env:FLSTUDIO_MCP_ENABLE_LEGACY_WRITES = '1'
try { .\.venv\Scripts\python.exe -m pytest tests -q }
finally { Remove-Item Env:FLSTUDIO_MCP_ENABLE_LEGACY_WRITES }

GUI operations require an interactive Windows desktop. Use an isolated preserved test project, stop transport, avoid simultaneous manual input, and retain checkpoints. fl_gui_save_as first establishes owned project identity. Existing compatible controller/loopMIDI bridge is needed for read-only verification and Playlist transport checks. Do not reinstall or overwrite an existing controller automatically. Review the example configuration separately; it is not merged into running configuration.

Bridge and candidate must share the private state directory for cooperating OS locks. Unrelated processes/manual edits cannot be locked. Unknown modals/layouts fail safely. Dev2 verifies one Sytrus factory-preset path, automation creation/move/curve-value edit, and strict saved/audio readback. No universal third-party, all-DPI, audio-clip or arbitrary routing/FX support. Private logs, screenshots, FLPs/WAVs and commercial content stay outside public source. A local ZIP is not GitHub publication.

Install Windows OCR language capabilities for the actual UI (tested zh-Hans and en-US). If OCR is unavailable or ambiguous, operations stop and retain diagnostics. Generator readback indices follow the current Channel Rack filter: select All through GUI and pass expected_channel to fl_plugin_state.