# VYNDR — LIVE TRACKING v1.0 (A1 board, Session 11)
### The read is locked pre-game. The game is watched. GRADES NEVER CHANGE IN-GAME — this layer is TRACKING, labeled as such, per the Ledger ethos.

## PRINCIPLES
1. **Zero out-of-pocket.** Free feeds only: statsapi.mlb.com (MLB live boxscore)
   and the ESPN site API (WNBA summary boxscore). No new dependency, no quota key.
2. **Grades never change in-game.** The locked pre-game read is untouched;
   live-progress marks are proto-outcomes rendered in the OUTCOME slot region
   (ROW-GRAMMAR §2 slot 6). Every live card carries the label
   "TRACKING — read locked pre-game" exactly once.
3. **One meaning per color.** Green = on-pace or already-cleared; amber =
   needs-more / caution; red stays reserved for settled-negative truth
   (miss / DEAD from NOT-IN-LINEUP). An in-progress prop is NEVER red.
4. **Only real box-line values.** A player not yet in the box score is ABSENT
   (no mark, no bar, no zero). `Number(null) === 0` is the classic fabrication
   bug — every numeric path uses strict null guards.
5. **An under is never "hit" until final.** Under semantics are HOLDS-IF: green
   HOLDING while the count sits under the line, amber LINE PASSED once the
   count reaches/passes it (counting stats can still be re-scored; nothing
   settles until the game is final — the settle pass owns the truth).
6. **DEAD is not declared here.** An over that "can no longer hit" is only
   honestly declarable for NOT-IN-LINEUP (S5, already shipped). Live tracking
   tracks until final; it never over-claims.

## DATA SOURCES (real shapes captured live, 2026-07-11)
- **MLB** — `GET statsapi.mlb.com/api/v1/schedule?sportId=1&date=YYYY-MM-DD&hydrate=linescore`
  identifies Live games (`status.abstractGameState === 'Live'`) AND carries the
  per-game linescore (currentInning / inningState / scheduledInnings) in the
  same call. Per live game: `GET /api/v1/game/{gamePk}/boxscore` →
  `teams.{home,away}.players.ID{personId}.stats.{batting,pitching}`. A player
  who hasn't appeared has EMPTY stats objects → absent.
- **WNBA** — ESPN scoreboard (already cached by scheduleService) identifies
  in-progress events (`status.type.state === 'in'`, `status.period`). Per live
  event: `GET site.api.espn.com/.../wnba/summary?event={id}` →
  `boxscore.players[].statistics[0]` with parallel `keys` + per-athlete
  `stats` string arrays. `didNotPlay` / empty stats → absent.

## STAT MAPS
- **MLB (LOCAL map, `LIVE_BOX_FIELD`)** — mirrors the idea of
  outcomeService.MLB_LOG_FIELD but is deliberately LOCAL: the live boxscore
  splits batting vs pitching into separate stat objects (the game log picks
  ONE group by position), and innings_pitched must be parsed in thirds
  ('5.2' = 5⅔ = 5.667) for live pace math. Wired stats: hits, total_bases,
  home_runs, rbi, runs, stolen_bases, doubles, walks (batting);
  strikeouts, earned_runs, innings_pitched, outs, hits_allowed (pitching).
- **WNBA (`WNBA_BOX_KEY`)** — points, rebounds, assists, steals, blocks,
  turnovers, threes (made, parsed from "M-A"), pra (points+rebounds+assists,
  computed only when all three components are present).

## PROP STATE (pure math, `web/src/lib/liveProgress.js`)
`propState({ side, line, current, progress })` →
- over, current > line → `hit` (✓ HIT — the over has already cleared; a
  counting stat cannot un-clear; still labeled TRACKING until the settle pass)
- over, not cleared → needs `N = floor(line) + 1 − current` (beats a push on
  integer lines); `on_pace` (green) when `current / progress ≥ floor(line)+1`,
  else `needs` (amber, "NEEDS N")
- under, current < line → `holding` (green HOLDS chip — never ✓ until final)
- under, current ≥ line → `past` (amber LINE PASSED — not red; nothing settled)
- current == null → NO state (absent beats wrong)
Progress fraction: MLB `(inning − (top ? 1 : 0.5)) / scheduledInnings`;
WNBA `(period − 0.5) / 4`, clamped to [0, 1].

## ENDPOINTS
- **`GET /api/live/:sport`** (public, rate-limited 60/min, mounted in app.js)
  → `{ sport, date, hasLive, updated_at, games: [{ id, home, away, progress:
  { label, fraction, inning|period, half }, players: { [nameKey]: { name,
  values: { stat_type: number } } } }] }`. mlb + wnba only; other sports →
  `{ hasLive: false, games: [] }`.
- **POLLING RULE:** the route reads `live:{sport}:{date}` (TTL 90s). On a cache
  MISS it consults the day's schedule; ONLY when the schedule shows live games
  does it fetch boxscores. Quota math: 1 schedule call + N boxscore calls per
  90s window across ALL users (shared cache), during live windows only — zero
  boxscore calls when nothing is live.
- **Next proxy** `web/src/app/api/live/[sport]/route.ts` (S25 rule — Express
  is not browser-reachable).

## FRONTEND (LIVE SLATE MODE)
- Slate polls `/api/live/{sport}` every 60s ONLY while live games are on
  screen (mlb/wnba, status 'in').
- `liveProgress.attachLiveProgress(strips, liveIndex)` (pure) joins built
  player strips to live values by nameKey + canonical statType; only graded,
  unsettled, non-dead props get `prop.live`.
- StatStrip renders the live mark in the OUTCOME slot region:
  `1/2 TB · ▲6th` + a small game-progress bar + the state chip
  (ON PACE green / NEEDS 2 amber / HIT ✓ green filled / HOLDS green /
  LINE PASSED amber). Actions (parlay +, BOOK IT) are suppressed on live
  props — the pre-game market for the locked line is closed.
- Live games with tracked props float to the top of the slate, ordered by
  proximity-to-hit (max over-fraction `current / needed-total`).
- The card label "TRACKING — read locked pre-game" renders once per live card.

## ACCEPTANCE CRITERIA
1. Parsers reproduce per-player values from REAL captured feed fixtures; a
   player absent from the box yields NO entry (never 0).
2. propState covers: over cleared / on-pace / needs-N / under-holds /
   under-passed / absent — unit-tested.
3. `/api/live/:sport` cache behavior: hit → no fetch; miss + live games →
   boxscore fetch + cache write; miss + no live games → schedule check only.
4. attachLiveProgress joins strips ↔ live index and never touches settled,
   dead, or ungraded props.
5. Full jest suite green from the worktree; `cd web && npm run build` exit 0.
6. If a game is genuinely live during the build, the service runs once against
   the real feed and the report shows a real tracked line.

## TEST PLAN
- `tests/unit/liveTrackingService.test.js` — MLB boxscore/linescore + WNBA
  summary parsers on real-shape fixtures; stat resolution incl. IP thirds;
  absent-player semantics; live-game identification from schedules.
- `tests/unit/liveProgress.test.js` — propState math table; progress
  fractions; attachLiveProgress; proximity sort.
- `tests/integration/liveRoute.test.js` — cache hit / miss+live / miss+idle /
  unknown sport, with injected deps (zero network).

— LIVE-TRACKING v1.0 · July 2026 —
