⛳ ParSense

A golf companion web app — AI caddie, live scorecard, course finder, and golf-specific weather. Built as a progressive web app: no backend, no accounts, installable on your phone, and it keeps working on the course when you lose signal.

Live: parsense-golf.netlify.app

A personal, non-commercial project. ParSense is built and shared for free with friends. It takes no payments, runs no ads, collects nothing server-side, and is not a commercial product or service. The weather and map data it uses is provided under free/non-commercial terms, and keeping the project non-commercial is what keeps that usage within those terms.

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Features

Profile

Your golfer profile drives personalization across the whole app — name, home town, handicap bracket, typical 18-hole score, and your driver / 7-iron carry distances. Click the avatar to generate a new randomized golf scene (sunsets, night skies with stars, bunkers, tree lines, and a golfer character with varied hair, skin tones, and outfits).

AI Coach

• Chat caddie — answers on slicing, hooking, putting, chipping, bunkers, course management, and pre-shot routine, personalized with your name and round history.
• Shot Planner — enter the distance to the pin plus wind and elevation, and it calculates what the shot plays like and picks the club from your bag. Pulls wind speed and temperature from the latest weather lookup automatically.

Course Selection

• Finds real golf courses near your home town (or your exact GPS location) using OpenStreetMap data.
• Shows address, distance, and — where verified — par, hole count, and yardage.
• Links straight to each course's real booking page and its rules/info page.
• Sort by closest, shorter courses first, or longer courses first.

Scoreboard

A live hole-by-hole scorecard. Editable par per hole to match the real card, color-coded results (birdie / bogey / double), OUT and IN subtotals, and a running Thru / Strokes / To Par summary. Auto-saves every tap, so you can close the app mid-round and pick up where you left off.

Round Archive

Saved rounds with computed stats — rounds played, average score, best score, average to par, and average putts.

Weather

Live conditions from Open-Meteo with a golf-specific verdict (wind affecting club selection, rain, cold killing carry distance, lightning warnings), plus an interactive precipitation radar centered on your location.

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Tech

Plain HTML, CSS, and JavaScript — no framework, no build step, no bundler. Open index.html and it runs.

Concern	Approach
Data storage	localStorage — per device, nothing leaves the browser
Weather	Open-Meteo (free, no API key)
Radar	Windy.com embed
Course data	OpenStreetMap via the Overpass API
Geocoding	Open-Meteo geocoding
Offline	Service worker caching the app shell

No API keys are required, and no server is needed.

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Development

Commits in this repository carry a Co-Authored-By: Claude trailer, reflecting that the project was built with AI assistance.

Running locally

Open index.html directly, or serve it (needed for the service worker and geolocation):

python -m http.server 5173

Then visit http://localhost:5173.

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Project structure

index.html      markup for all six tabs
style.css       styling, theming, light/dark palettes
app.js          all application logic
sw.js           service worker (offline support)
manifest.json   PWA manifest
icon-192.png    app icons
icon-512.png

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Privacy

What stays on your device: profiles, rounds, scores, and your avatar live in your browser's localStorage. There is no backend, no account, and no analytics. Each person who opens the app gets their own independent copy, and nobody can see anyone else's data.

What leaves your device: ParSense talks to third-party services to answer requests, and those requests necessarily include your IP address plus:

Service	What it receives	Why
Open-Meteo	The town you type, then its coordinates	Weather conditions and geocoding
Overpass / OpenStreetMap	Coordinates of your home town, or your GPS position if you use "Use my exact location"	Finding nearby courses
Windy.com	Coordinates, via an embedded iframe	Precipitation radar
Google	Course name, only when you click a fallback search link	Finding tee times / rules

The Windy radar is a third-party embed and may set its own cookies. If you deploy this for others, that is worth disclosing to them — it's the one component that could carry tracking you don't control.

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Known limitations

• The coach is rule-based keyword matching, not a large language model.
• Par and yardage are only shown for courses that have been manually verified; OpenStreetMap carries no par data.
• Course hours are rarely published to OpenStreetMap, so most courses show "Hours not listed" rather than a guessed time.
• Course length is used as a rough proxy for difficulty — slope and course ratings aren't available in any free dataset.
• Data does not sync between devices or browsers.