mcp-garmin/server.py

import json
import os
import queue
import threading
from datetime import date

from garminconnect import Garmin, GarminConnectAuthenticationError
from mcp.server.fastmcp import FastMCP

mcp = FastMCP("garmin")

_client: Garmin | None = None
_auth_state: str = "unauthenticated"
_mfa_input_queue: queue.Queue = queue.Queue()
_login_result_queue: queue.Queue = queue.Queue()


def _today() -> str:
    return date.today().isoformat()


def _check_auth() -> str | None:
    if _auth_state != "authenticated":
        return "Not authenticated. Ask Claude to call authenticate() first."
    return None


def _prompt_mfa() -> str:
    return _mfa_input_queue.get(timeout=300)


def _startup_login() -> None:
    global _client, _auth_state
    email = os.environ.get("GARMIN_EMAIL")
    password = os.environ.get("GARMIN_PASSWORD")
    if not email or not password:
        raise SystemExit(
            "GARMIN_EMAIL and GARMIN_PASSWORD environment variables are required."
        )
    try:
        _client = Garmin(email, password)
        _client.login()
        _auth_state = "authenticated"
    except Exception:
        _auth_state = "unauthenticated"


@mcp.tool()
def authenticate() -> str:
    """Initiate Garmin authentication using credentials from environment variables."""
    global _client, _auth_state

    email = os.environ.get("GARMIN_EMAIL", "")
    password = os.environ.get("GARMIN_PASSWORD", "")
    if not email or not password:
        return "GARMIN_EMAIL and GARMIN_PASSWORD environment variables are required."

    def _do_login() -> None:
        try:
            _client.login()
            _login_result_queue.put(("success", None))
        except Exception as exc:
            _login_result_queue.put(("error", str(exc)))

    _client = Garmin(email, password)
    _client.prompt_mfa = _prompt_mfa
    threading.Thread(target=_do_login, daemon=True).start()

    try:
        status, err = _login_result_queue.get(timeout=10)
        if status == "success":
            _auth_state = "authenticated"
            return "Authenticated successfully."
        return f"Authentication failed: {err}"
    except queue.Empty:
        _auth_state = "mfa_pending"
        return (
            "MFA required. Garmin has sent a verification code to your registered "
            "email or phone. Call complete_mfa(code) with the code you received."
        )


@mcp.tool()
def complete_mfa(code: str) -> str:
    """Provide the MFA verification code to complete Garmin authentication."""
    global _auth_state

    if _auth_state != "mfa_pending":
        return "No MFA in progress. Call authenticate() first."

    _mfa_input_queue.put(code)

    try:
        status, err = _login_result_queue.get(timeout=30)
        if status == "success":
            _auth_state = "authenticated"
            return "MFA accepted. Authenticated successfully."
        return f"Authentication failed after MFA: {err}"
    except queue.Empty:
        return "Timed out waiting for authentication to complete."


@mcp.tool()
def get_activities(start_date: str = "", end_date: str = "", limit: int = 20) -> str:
    """List Garmin activities between two dates (YYYY-MM-DD). Defaults to today."""
    if err := _check_auth():
        return err
    start = start_date or _today()
    end = end_date or _today()
    try:
        result = _client.get_activities_by_date(start, end)
        return json.dumps(result[:limit], indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching activities: {exc}"


@mcp.tool()
def get_activity_details(activity_id: str) -> str:
    """Get full details for a single activity by its ID (splits, laps, metrics)."""
    if err := _check_auth():
        return err
    try:
        result = _client.get_activity_details(activity_id)
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching activity details: {exc}"


@mcp.tool()
def get_sleep(date: str = "") -> str:
    """Get sleep data for a date (YYYY-MM-DD): score, stages, duration. Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_sleep_data(cdate)
        if not result:
            return f"No sleep data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching sleep data: {exc}"


@mcp.tool()
def get_heart_rate(date: str = "") -> str:
    """Get heart rate data for a date (YYYY-MM-DD): resting HR and daily timeline. Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_heart_rates(cdate)
        if not result:
            return f"No heart rate data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching heart rate data: {exc}"


@mcp.tool()
def get_stress(date: str = "") -> str:
    """Get stress level timeline for a date (YYYY-MM-DD). Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_stress_data(cdate)
        if not result:
            return f"No stress data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching stress data: {exc}"


@mcp.tool()
def get_body_battery(date: str = "") -> str:
    """Get body battery charge/drain values for a date (YYYY-MM-DD). Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_body_battery(cdate, cdate)
        if not result:
            return f"No body battery data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching body battery data: {exc}"


@mcp.tool()
def get_hrv(date: str = "") -> str:
    """Get HRV status and nightly average for a date (YYYY-MM-DD). Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_hrv_data(cdate)
        if not result:
            return f"No HRV data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching HRV data: {exc}"


@mcp.tool()
def get_spo2(date: str = "") -> str:
    """Get SpO2 (blood oxygen) readings for a date (YYYY-MM-DD). Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_spo2_data(cdate)
        if not result:
            return f"No SpO2 data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching SpO2 data: {exc}"


@mcp.tool()
def get_steps(date: str = "") -> str:
    """Get step count and daily goal for a date (YYYY-MM-DD). Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_steps_data(cdate)
        if not result:
            return f"No steps data found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching steps data: {exc}"


@mcp.tool()
def get_daily_stats(date: str = "") -> str:
    """Get daily summary for a date (YYYY-MM-DD): calories, floors, intensity minutes. Defaults to today."""
    if err := _check_auth():
        return err
    cdate = date or _today()
    try:
        result = _client.get_stats(cdate)
        if not result:
            return f"No daily stats found for {cdate}"
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching daily stats: {exc}"


@mcp.tool()
def get_devices() -> str:
    """List paired Garmin devices with model name and firmware version."""
    if err := _check_auth():
        return err
    try:
        result = _client.get_devices()
        if not result:
            return "No devices found."
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching devices: {exc}"


@mcp.tool()
def get_gear() -> str:
    """List gear items (shoes, bikes) with mileage and usage stats."""
    if err := _check_auth():
        return err
    try:
        result = _client.get_gear(_client.display_name)
        if not result:
            return "No gear found."
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching gear: {exc}"


@mcp.tool()
def get_user_profile() -> str:
    """Get Garmin user profile: display name, age, weight, and HR zones."""
    if err := _check_auth():
        return err
    try:
        result = _client.get_user_profile()
        if not result:
            return "No user profile found."
        return json.dumps(result, indent=2)
    except GarminConnectAuthenticationError:
        return "Authentication error. Call authenticate() again."
    except Exception as exc:
        return f"Error fetching user profile: {exc}"


if __name__ == "__main__":
    _startup_login()
    mcp.run()