flemcee

MCP server for FL Studio powered by the flapi Python client. It exposes FL Studio control by executing Python inside FL Studio via Flapi.

See /Users/tylertt/flemcee/WORKLOG.md for an implementation summary and /Users/tylertt/flemcee/ROADMAP.md for the future plan.

Prerequisites

• flapi installed and working (FL Studio configured with Flapi scripts).
• FL Studio running with the Flapi server loaded.
• macOS: keep flapi port-host running while FL Studio is open.

Install

python -m venv .venv
source .venv/bin/activate
pip install -U pip
pip install -e .

Run

Default MCP transport is streamable HTTP:

python -m flemcee

To use stdio transport:

FLEMCEE_TRANSPORT=stdio python -m flemcee

Configuration

Environment variables:

• FLEMCEE_TRANSPORT: MCP transport (streamable-http, stdio, or sse).
• FLEMCEE_REQ_PORT: MIDI request port name (default: Flapi Request).
• FLEMCEE_RES_PORT: MIDI response port name (default: Flapi Response).
• FLEMCEE_CONNECT_ON_START: set to true to connect to FL Studio at startup.
• FLEMCEE_LOG_LEVEL: logging level (default: INFO).
• FLEMCEE_HOST: server host when supported by the MCP transport (default: 127.0.0.1).
• FLEMCEE_PORT: server port when supported by the MCP transport (default: 8000).
• FLEMCEE_MOUNT_PATH: optional base mount path for HTTP transports.
• FLEMCEE_STREAMABLE_HTTP_PATH: optional streamable HTTP endpoint path.
• FLEMCEE_SSE_PATH: optional SSE endpoint path.
• FLEMCEE_GENERATE_TOOLS: set to true to register per-function tools from stubs (default: true).
• FLEMCEE_CURATED_TOOLS: set to true to register curated higher-level tools (default: true).

MCP Tools

• fl_connect(force: bool = false)
• fl_disconnect()
• fl_status()
• fl_exec(code: str)
• fl_eval(expression: str)
• fl_call(target: str, args: list = [], kwargs: dict = {})
• fl_catalog(module: str | None = None, include_docs: bool = False)
• fl_symbol_lookup(symbol: str, include_docs: bool = False)
• fl_symbol_resolve(target: str, include_docs: bool = False)

Curated tools (auto-generated at startup):

• fl_session_summary()
• fl_transport_play()
• fl_transport_stop()
• fl_transport_record_toggle()
• fl_transport_set_loop_mode(mode: str | int)
• fl_transport_set_song_pos(position: float | int, mode: int = -1)
• fl_project_set_tempo(bpm: float)
• fl_channel_list(global_count: bool = False, use_global_index: bool = False)
• fl_channel_set(index: int, name: str | None, color: int | None, volume: float | None, pan: float | None, pitch: float | None, target_fx_track: int | None, use_global_index: bool = False)
• fl_channel_select(index: int, use_global_index: bool = False)
• fl_pattern_list(include_defaults: bool = False)
• fl_pattern_select(index: int)
• fl_pattern_rename(index: int, name: str)
• fl_sequencer_set_steps(channel_index: int, steps: list[int], value: bool = True, use_global_index: bool = False)
• fl_sequencer_clear_steps(channel_index: int, length: int = 16, use_global_index: bool = False)
• fl_mixer_list_tracks(max_tracks: int = 125)
• fl_mixer_set_track(index: int, volume: float | None, pan: float | None, mute: bool | None, solo: bool | None, arm: bool | None)
• fl_mixer_route(source_index: int, dest_index: int, enabled: bool = True, level: float | None = None, update_ui: bool = True)
• fl_plugin_list_params(index: int, slot_index: int = -1, limit: int = 64, use_global_index: bool = False)
• fl_plugin_set_param(index: int, param_index: int, value: float, slot_index: int = -1, use_global_index: bool = False)
• fl_plugin_next_preset(index: int, slot_index: int = -1, use_global_index: bool = False)
• fl_beat_make_hiphop(kick_channel: int, snare_channel: int, hat_channel: int, bars: int = 1, style: str = \"boom_bap\")
• fl_mix_balance_peaks(track_indices: list[int], target_peak: float = 0.8, mode: int = 2, min_volume: float = 0.0, max_volume: float = 1.0, max_change: float | None = 0.2)

MCP Resources

• flstudio://catalog
• flstudio://module/{module}

Notes

• fl_exec and fl_eval run inside FL Studio's Python environment.
• Use fl_call for convenience (e.g. target="transport.start").
• The API catalog tools read from fl-studio-api-stubs, providing signatures and documentation when available.
• When stub-based tool generation is enabled, each top-level FL Studio function is registered as a tool named fl_<module>_<function>.

Examples

See /Users/tylertt/flemcee/EXAMPLES.md for complete workflows:

• “Listen to this project and do a mix”
• “Take this loop and sequence it out into a full hip hop beat”