Historical Baseball MCP Server

@pipeworx/historical-baseball

Historical MLB statistics: career batting/pitching lines, team-season records, per-game box-score summaries, and season leaderboards, back to 1871. Fleet #2976 — the live mlb-stats pack only covers the current MLB Stats API; this pack is the historical record underneath it.

Part of Pipeworx — an MCP gateway connecting AI agents to 1786+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

• baseball_player_history(player) — year-by-year batting and/or pitching stats for one player's whole career. Pass a name ("Babe Ruth") or an exact Lahman player_id ("ruthba01"). An ambiguous name returns a candidate list (with player_id) instead of guessing.
• baseball_team_season(team, year) — one team's full-season record for one year: wins/losses, division/league/World Series result, team batting and pitching totals, park and attendance. Pass a code ("NYA") or common name ("Yankees").
• baseball_game_log(date, team) — box-score-level summary of the game(s) one team played on one date (an array, so doubleheaders return two games): final score, winning/losing/save pitcher, managers, and each side's AB/H/2B/3B/HR/RBI/BB/SO/errors. Covers regular season plus All-Star, Division Series, League Championship Series, Wild Card and World Series games (game_type: R/A/D/L/C/W).
• baseball_season_leaders(year, stat, league?, limit?) — top-N leaderboard for one batting or pitching stat in one season. Batting: HR, AVG, RBI, R, H, SB, BB, SO, 2B, 3B. Pitching: W, ERA, SO_P, SV, L, WHIP. AVG/ERA/ WHIP apply a simple qualifying floor (AB>=100 / IPouts>=100), not MLB's official plate-appearance/innings qualifying rule.
• baseball_coverage() — the loaded Retrosheet date range, latest Lahman season year, and when it was last refreshed. Call this if a date/year you expect to exist comes back not-found.

Team codes changed for several relocated/renamed franchises (e.g. the Athletics' Retrosheet code changed for the 2025 move to Sacramento); both the old and new codes exist in the data where applicable, and a handful of common names and well-known defunct franchises resolve automatically (see TEAM_ALIASES in src/store.ts). An unrecognized team/year/date/stat is refused with a clear error, never an empty success.

Auth

Keyless. The tools answer only through the Pipeworx gateway, which holds the data; a standalone npm install has no data to read, and every tool throws a clear "not bound in this runtime" error there instead of returning an empty list.

Data sources

• Retrosheet (retrosheet.org/gamelogs) — one row per game, 1871-2025. Free with a required attribution notice, reproduced verbatim in every baseball_game_log response:

  The information used here was obtained free of charge from and is copyrighted by Retrosheet. Interested parties may contact Retrosheet at "www.retrosheet.org".

• SABR Lahman Baseball Database (sabr.org/lahman-database) — season batting/pitching/team tables and player bios, 1871-2025 (now including Negro Leagues statistics licensed from Seamheads.com), maintained by SABR from Sean Lahman's original donation. Licensed CC BY-SA 3.0 Unported (Creative Commons Attribution-ShareAlike):

  This database is copyright 1996-2025 by SABR, via generous donation from Sean Lahman. This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. For details see: http://creativecommons.org/licenses/by-sa/3.0/

Neither source publishes a live query API — both ship bulk files only — so this pack builds a copy rather than proxying (CLAUDE.md "BUILD THE COPY"). Scope: season and game AGGREGATES only. Retrosheet's play-by-play EVENT files are never loaded; game logs are already one row per game and Lahman's tables are already one row per player-team-season, so unlike a raw-flight or raw-delivery source, neither needed an aggregation step here.

Licensing and ShareAlike compliance

The Lahman tables (people, batting_season, pitching_season, teams_season) are built from SABR's bulk files rather than answered by calling SABR live per request — and CC BY-SA 3.0's ShareAlike term applies to that kind of build, not to calling an upstream live. Concretely, that means:

• Attribution (BY): every response from a Lahman-backed tool carries source (SABR/Sean Lahman), source_url (sabr.org/lahman-database) and the full license text in license, and this README states it again.
• ShareAlike: because we hold and redistribute a derivative of these specific four tables (via the tool responses above), that derivative is itself licensed CC BY-SA 3.0 — same as the source, not more restrictively. If you build a product on data returned by baseball_player_history, baseball_team_season or the batting/pitching side of baseball_season_leaders, your own adaptation of that data carries the same CC BY-SA 3.0 obligation: credit SABR/Sean Lahman, and license your own redistribution of it under CC BY-SA 3.0 or a compatible license.
• This does not extend to the Retrosheet-backed baseball_game_log data, which carries only Retrosheet's own attribution requirement (quoted above), no ShareAlike term.
• It does not restrict anything else in the Pipeworx catalog — ShareAlike "infects" only the specific copied/adapted work, not an unrelated codebase that happens to also call this gateway (the same reasoning as the symmap precedent in CLAUDE.md, applied to a license that actually requires it rather than one that was waived).

Refreshing or extending the data

node scripts/historical-baseball/load-data.mjs
# Retrosheet only (skip re-downloading/parsing Lahman's local CSVs):
node scripts/historical-baseball/load-data.mjs --skip-lahman
# Lahman only, once new CSVs are in place:
node scripts/historical-baseball/load-data.mjs --skip-retrosheet

Retrosheet is fully automated. The loader downloads https://www.retrosheet.org/gamelogs/gl1871_2025.zip (a stable combined bulk file covering 1871-2025 plus All-Star/postseason game logs) directly — no manual step. Re-run once Retrosheet publishes the following season's combined zip (check https://www.retrosheet.org/gamelogs/ for a newer gl1871_20XX.zip, or a standalone gl20XX.zip before the combined file is updated).

Lahman is NOT automated and needs a one-time manual download. SABR distributes the comma-delimited release through signed per-file Box.com links (sabr.box.com/s/<share-id>/file/<id>) minted by Box's web app — there is no stable, curlable URL for the CSVs themselves (unlike Retrosheet's zip). To refresh:

1. Open https://sabr.org/lahman-database/ and follow the "Comma-delimited version" link (currently sabr.box.com/s/...) under "Download latest version".
2. Download Teams.csv, People.csv, Batting.csv and Pitching.csv from that Box folder into a local directory.
3. Run the loader with --lahman-dir <that directory> (defaults to ../lahman-csv relative to this repo's root, i.e. a sibling of the pipeworx checkout).

Each run replaces every table (DROP + reload), because SABR republishes corrected editions of the whole file rather than publishing incremental diffs, so a clean reload is the only way to avoid stale rows from a previously-corrected season lingering alongside the new data.

Needs wrangler logged in to the Pipeworx Cloudflare account for either source.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "historical-baseball": {
      "url": "https://gateway.pipeworx.io/historical-baseball/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/historical-baseball/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — ask_pipeworx, discover_tools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Both URLs reach the same gateway and the same 1786+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

No MCP client? Call it over HTTP

curl -X POST https://gateway.pipeworx.io/v1/tools/baseball_player_history \
  -H 'Content-Type: application/json' \
  -d '{"player":"Babe Ruth"}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/baseball_player_history. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.

Standalone (no gateway account)

This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:

{
  "mcpServers": {
    "historical-baseball": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-historical-baseball"]
    }
  }
}

Or run it directly to confirm it starts:

npx -y @pipeworx/mcp-historical-baseball

It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call for only this pack's tools — none of the shared meta-tools the gateway connection above adds. Same source, same tools, no ask_pipeworx routing.

Using with ask_pipeworx

Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:

ask_pipeworx({ question: "your question about Historical Baseball data" })

The gateway picks the right tool and fills the arguments automatically.

More

• Docs and guides
• pipeworx.io

License

MIT