Baseball extensions

Baseball extensions provide additional source observations through explicit /extended routes. Existing baseball responses, calculations, units and ordering retain their legacy behavior. Availability depends on deployment, enrichment and the selected league/season; full STATS parity is not claimed.

Request additional observations

Use /v1/mlb, /v1/kbo or /v1/npb with these paths:

Path	Result
/games/{id}/extended	Game metadata, officials and extended box-score observations
/games/{id}/pbp/extended	Source action/pitch events and supported runner/fielding details
/games/{id}/team-stats/extended	Game observations containing team statistics and coverage
/players/{id}/extended	Profile, draft, published awards or salary observations where supported
/teams/{id}/extended	Team metadata, coaches and draft observations
/venues/{id}/extended	Verified venue observations
/players/{id}/season-stats/extended	Role, team-stint and position-specific season statistics
/teams/{id}/season-stats/extended	Official team totals or full team player tables, explicitly labeled
/standings/extended	Available league-specific standings observations
/leaders/extended	Observed player rankings, ties and coverage
/transactions	Explicit published transactions, with pagination
/umpire-stats/extended	Available umpire statistical observations; currently conditional
/stat-definitions	Calculation methods, units and missing-value rules

Season statistics, standings, leaders, transactions and umpire statistics require season=2025 or another explicit season. Statistical requests default to game_type=regular. Postseason and preseason observations are separate and are not synthesized. Transactions default to game_type=unknown. To retrieve current profile observations, omit the season filter; current profiles use season 0. Awards and draft observations can have an explicit season.

Most responses contain data.observations, data.next_cursor and data.coverage. Each observation identifies its producer, observation time, source URL, season and game type. Follow next_cursor using cursor; limit defaults to 50 and is capped at 100. Cursor order is canonical extension ID, not event chronology. Producers remain separate, so clients should not sum duplicate source totals. All extension responses bypass legacy caches.

Interpreting statistics

reported_counts contains mapped provider counts. derived contains separately calculated metrics. source_statistics retains source values whose definition may require further verification. The statistic-definition endpoint explains formulas and prerequisites. Missing values stay null; valid zero remains zero. Rates are calculated from totals, not averaged percentages. Innings use integer outs internally: 6.1 innings means 19 outs.

Fielding retains the reported position. NPB aggregate outfield rows are not LF/CF/RF statistics. NPB team tables include nonqualifying players; unresolved names remain visible in team observations and are not assigned to a guessed player. KBO fielding stolen bases/caught stealing are defensive counts, distinct from offensive baserunning.

Leaderboards rank observed rows in descending order. Ties are computed before limiting, qualification remains unknown, and ambiguous duplicate or traded-player rows are excluded rather than double-counted. These are not certified official league leaderboards.

Source differences

MLB extensions can expose official position-level statistics, explicit transactions, broadcasts, split-squad flags, draft/award observations, coaches, standings indicators and rich game events. KBO extensions include official fielding/profile observations and Naver season/game/relay data. NPB extensions include official full team statistics, profiles and published MVP voting plus SPAIA game/pitch observations. MVP weighted points are reconciled with the published 5/3/1 weights; unresolved names are not guessed.

KBO current salary observations are labeled KRW with unknown historical season applicability. A transaction or roster activation does not establish medical recovery. NPB surname-only officials do not establish unique umpire identities. Exact end timestamps are not calculated from durations. Provider revision timestamps are not event-occurrence timestamps. SPAIA overlay coordinates are uncalibrated.

Legacy PBP already includes pitch/play ordering, outcomes, speed, timestamps and outs after plays where available; MLB also retains runner movements. Extensions add detail without changing those fields. MLB’s 2026 Statcast CSV plate-coordinate/strike-zone definitions are documented separately from native feed coordinates.

Coverage limits

Public source samples and parser tests are not complete production coverage measurements. 2025/2026 coverage must be measured separately for MLB, KBO and NPB against authoritative schedules and player populations. Empty observations do not imply a statistic equals zero.

KBO/NPB postseason qualification, umpire season statistics, other voting histories and specialist situational splits remain conditional. Exact proprietary STATS analytics, complete tracking, contracts and medical timelines are not established. No unannounced awards or unsupported historical values are manufactured. Website publication and production enablement are verified separately from source updates.