ephys-mcp

An MCP server that lets an LLM analyse intracortical (spike-level) brain-computer-interface recordings: signal quality, spike detection, firing rates, and cursor-velocity decoding.

Existing BCI MCP servers target scalp EEG. This one targets the kind of data a high-channel-count implant produces, and defines a read-only adapter contract so a live device backend can be added when a vendor publishes an API.

Research and education software. Not a medical device. Not for clinical use. Not affiliated with or endorsed by Neuralink Corp. or any other implant manufacturer.

Status

v0.4, early. Working today: local NWB files, local broadband WAV recordings, live Lab Streaming Layer streams, streaming from the DANDI Archive, a synthetic motor-cortex source with ground truth, spike detection, quality metrics, ridge and Kalman decoders, trial-aligned PSTHs, spike sorting, cross-session (FALCON-style) evaluation, latent-factor models (GPFA, PCA), and figures. Planned: probe geometry for sorting.

Install and run

Needs uv. No install step: uvx ephys-mcp fetches the package and starts the server on stdio.

Claude Code:

claude mcp add ephys -- uvx ephys-mcp

Claude Desktop (claude_desktop_config.json):

{ "mcpServers": { "ephys": { "command": "uvx", "args": ["ephys-mcp"] } } }

From a checkout, use uv run ephys-mcp instead, or uv --directory /path/to/ephys-mcp run ephys-mcp in the configs above.

HTTP transport

For remote clients or hosted agents, serve streamable HTTP instead of stdio:

EPHYS_MCP_TOKEN='a-long-random-secret' uvx ephys-mcp --http --host 0.0.0.0 --port 8000

Every request must then carry Authorization: Bearer <token>. The server refuses to bind to a non-loopback address without a token, and tokens must be at least 16 characters. Put TLS in front of it (a reverse proxy) before exposing it beyond a private network: the token travels in clear text otherwise. On loopback the token is optional, so ephys-mcp --http alone serves http://127.0.0.1:8000/mcp for local testing.

Then ask, for real data: "Find a small motor cortex dataset on DANDI, open it, and tell me how well hand velocity can be decoded." Or offline: "Open a synthetic session, check signal quality, fit a Kalman decoder and show me a decoded window."

Data sources

Source	What it opens
synthetic	Simulated units tuned to cursor velocity, with broadband signal and ground truth
nwb	A local .nwb file (params.path)
wav_dir	Local broadband WAV (params.path): a folder of mono clips, one channel each, or one multi-channel file
lsl	A live Lab Streaming Layer broadband stream on the local network; keeps the most recent buffer_s of signal. Needs uvx --with 'ephys-mcp[lsl]' ephys-mcp
dandi	An NWB file streamed from the DANDI Archive by HTTP range requests; nothing is mirrored
n1_stub	Not implemented. Documents how a live implant adapter would be written on the same base as lsl

Dataset licence and citation come from the archive and are returned by open_session, so the model can attribute the data. Many datasets record only during trials; the server tracks those spans (recorded_fraction) and leaves the gaps out of rates and decoding instead of reading them as silence.

WAV samples carry no physical unit, so amplitudes are reported as ADC counts unless you pass uv_per_count; every amplitude result names its unit. Clips in a folder are separate recordings, so the server says that timing across those channels is not meaningful. Spike times from WAV are threshold crossings, not sorted units.

Reference results, all simple causal linear baselines rather than state of the art:

• MC_Maze_Small (DANDI 000140, 142 units, last 20% held out, 50 ms bins): ridge R² 0.50, Kalman R² 0.34 for hand velocity.
• FALCON H1 (DANDI 000954, human 7-DoF velocity, 176 channels, 20 ms bins, eval_mask): ridge trained on the first held-in day scores R² 0.43 on that day's minival, 0.07 one week later and below zero on the held-out days. That decay is the point of the benchmark; the Kalman filter is unsuitable for this scripted calibration data. FALCON's official test labels are private, so these are not leaderboard scores.

Decoder hyperparameters (ridge strength, the neural lead for Kalman) are chosen by blocked cross-validation inside the training split. Ridge history is 0.5 s of spike counts whatever the bin size.

GPFA is implemented from the paper's equations in numpy and scipy (EM over loadings, offsets, noise and per-factor timescales; no deep-learning dependency), and runs in seconds on a hundred trials. On the simulator, whose true latent is 2-D cursor velocity, it finds two dominant factors that explain velocity with R² 0.95 (PCA: 0.68). On MC_Maze_Small it shows the rotating population trajectory around movement onset that motor cortex is known for. LFADS-class models are out of scope: they need a training run of minutes and a deep-learning stack.

Tools

Tool	Purpose
list_sources	Source types and their parameters
search_datasets	Search DANDI, or list curated intracortical datasets
list_dataset_files	Licence, citation and NWB files of a DANDI dataset
list_lsl_streams	LSL streams visible on the network
get_stream_status	For a live session: buffered span, whether data is arriving, drops
open_session / close_session	Session lifecycle
get_session_info	Channels, rates, behaviour signals, licence, citation
get_signal_quality	Noise, SNR, dead/noisy channels
detect_spikes	Threshold crossings; precision/recall when truth exists
sort_spikes	Spike-sort a broadband window with spikeinterface (sort extra); the session then uses the sorted units
get_firing_rates	Population rate summary
fit_decoder	Ridge or Kalman, scored on held-out data; hyperparameters chosen inside the training split
decode_window	Decoded-vs-true preview for a window
evaluate_cross_session	Fit on one session, score unchanged on others: does a decoder survive to a later day? Honours FALCON's eval_mask
get_psth	Firing aligned to a trial event, optionally grouped by a trial column or limited to some units
fit_latent_factors	GPFA (Yu et al. 2009) or PCA on trial-aligned activity: single-trial latent trajectories, variance per factor, timescales, and how well the top factors explain a velocity signal
plot_latent_factors	Figure: top three factors over time, the factor-1/factor-2 state space, and variance per factor
plot_psth	Figure: PSTH per group with SEM, above a unit-by-time heatmap of change from baseline
plot_raster	Figure: spike raster, unrecorded spans shaded
plot_decoding	Figure: decoded against actual behaviour, one panel per dimension

Resource: ephys://sessions. Prompts: analyze_session, falcon_evaluate.

Tools return summaries, never raw arrays, so results fit in a model's context.

Optional extras

Extra	Adds	Install
lsl	the lsl live source	uvx --with 'ephys-mcp[lsl]' ephys-mcp
sort	sort_spikes via spikeinterface's built-in sorters (spykingcircus2, tridesclous2); about 330 MB of dependencies	uvx --with 'ephys-mcp[sort]' ephys-mcp

Sorting treats channels as independent electrodes because sources carry no probe geometry yet, so it suits single-electrode arrays rather than dense probes. On the simulator, spykingcircus2 recovers every unit with recall above 0.95.

Plot tools return the PNG inline, so a vision-capable model can read the figure, and also save it under ~/.cache/ephys-mcp/plots (override with EPHYS_MCP_OUTPUT_DIR). Figures use a categorical palette checked for colour-blind separation, with direct labels so identity never rests on colour alone.

Design rules

• Read-only. The NeuralSource contract has no write, stimulate or configure method. None will be added without a separate safety design.
• Local by default. stdio transport, no telemetry. HTTP is opt-in and token-gated. Neural data is sensitive.
• No bundled third-party data. See DATA_LICENSES.md.

Writing a source adapter

For recordings, subclass ephys_mcp.sources.base.NeuralSource (info, read_raw, spike_times, behavior). For a live device, subclass ephys_mcp.sources.live.RingBufferSource and call push(samples) from a reader thread; sources/lsl.py is a complete example in about 60 lines, and sources/n1_stub.py lists what an implant adapter would additionally need. Register the class in ephys_mcp/sources/__init__.py.

Live sessions report time as seconds since open, and only the most recent buffer is readable, so t_start_s and duration_s move forward.

Development

uv run pytest              # offline
uv run pytest -m network   # also streams a real file from DANDI
uv run ruff check .

Licence

CC0 1.0 Universal. The authors waive all copyright and related rights to the extent the law allows. Use it for anything, no attribution required. CC0 does not grant patent or trademark rights.