Final Ball
"We create the chance, you finish it."
An AI agent for Fantasy Premier League managers. Every gameweek it recommends a transfer (top pick + 3 alternatives, or "Save it"), a captain, and when to play chips — and then tracks whether its advice worked.
Positioning: accountable advice. Every suggestion shows its full reasoning and scores itself against what actually happened.
Live at finalball.manavpkothari.dev · v0.1 MVP in progress · Roadmap
What's built
Infrastructure
- Monorepo: pnpm workspaces (
/apps/web, /packages/agent, /scripts)
- Auth: Google OAuth (Supabase) — sign-up and sign-in are one button
- Database: Supabase Postgres
- Hosting: Vercel Hobby
- Scheduler: GitHub Actions (daily data refresh + weekly brief generation)
- Domain:
finalball.manavpkothari.dev with DNS on Vercel
Onboarding
- Find your team by country + country rank + team name — no URLs or IDs needed for most users
- Tie-size probe (binary search) estimates scan time before starting
- Rotating progress text tied to real scan progress
- "Use my FPL link instead" after 5 seconds; 30-second cap with URL fallback
- "Is this you?" confirmation card; one account per team
Agent (packages/agent)
The core analysis pipeline, framework-agnostic:
generateTransfers(teamId) → { transfers, trace: TraceStep[], meta }
- Load context — squad, bank, free transfers (derived from history), fixtures
- Score players —
ep_next × availability for GW1; form × fdrMultiplier × availability for GW2/3; blank GW = 0; DGW = ×2
- Rank weak spots — pts/£m; backup GK gets a minimum floor to avoid dominating the sell list
- Find candidates — same position, affordable, not owned, status not unavailable
- Apply constraints — max 3 per club; 2-transfer pairs checked jointly
- Rank with model —
claude-sonnet-4-6 via tool use, returns structured JSON (top pick + 3 alternatives + "why sell" + full reasoning sections)
- Validate picks — re-checks model choices against constraints; records replans; falls back to deterministic ranking after 2 replans
- Trace — every step emits
{n, title, text, replan?} in plain language with real numbers
Save threshold: +1.0 pts over 3 GWs — below that, rolling the transfer is recommended.
UI (apps/web)
- Next.js App Router + Tailwind + shadcn/ui
- Sign-in, team linking, and post-auth routing (brief ↔ onboarding)
/brief, /onboarding, /privacy pages- FPL client hardening: jitter, 503 hold, two-layer cache, per-key TTLs
- FPL health endpoint at
/api/fpl-health
- Design system: dark-first, IBM Plex Sans + Mono, orange accent (
#FF8A1F), 10 components
Roadmap
v0.1 — Core MVP (target: 25 October 2026)
Full MVP (target: ~20 November 2026)
- Scheduled weekly brief generation + one email per gameweek
- Refresh button (max 3 per gameweek)
- Chips: timing advice, expiry nudges, weekly alert card
- Stick-or-diverge check-in
- Next-week preview
- Transfer receipts + 5-gameweek scorecard
- Decision journal
- Demo mode (frozen snapshot + live toggle)
- Light mode, full motion
Post-MVP
- "Ask the agent" — text and voice ("why not X?")
- Hits tied to aggression setting
- Wildcard and Free Hit squad builders
- Rival mode — league ownership badge, differentials, gap context
Stack
| Layer | Choice |
|---|
| Frontend | Next.js App Router, Tailwind, shadcn/ui |
| Agent | Node, TypeScript, @anthropic-ai/sdk |
| Auth + DB | Supabase (Google OAuth + Postgres) |
| Hosting | Vercel Hobby |
| Scheduler | GitHub Actions |
| Model | claude-sonnet-4-6 via ANTHROPIC_MODEL env var |
| Email | Nodemailer → Resend SMTP |
Running locally
pnpm install
# Run the web app
pnpm dev
# Run the agent CLI against a team
pnpm agent:run -- --team <teamId>
# Run agent tests
pnpm --filter @finalball/agent test
Requires .env.local in apps/web/ — see .env.example.
Docs
Not affiliated with the Premier League or Fantasy Premier League.
