matchwire Docs

Introduction

matchwire returns one row per game, matched across Kalshi, Polymarket US, Polymarket International and Predict.fun. Each row keeps every venue's own market ID and a ready-made request for it. Mapping only: no prices or order books.

Get a key

You get a key when you start a plan. Send it on every call as the x-api-key header. Your plan decides which venues and sports the key can read.

All calls go to https://api.matchwire.win with your key in the x-api-key header. Responses are JSON. Send Accept-Encoding: gzip for smaller responses.

First call

Ask for the games you want. This gets upcoming NFL games:

curl -H "x-api-key: YOUR_KEY" \
  "https://api.matchwire.win/api/v1/rows?sport=nfl&status=scheduled"

Narrow it more with comma lists: venue=kalshi,poly, type=winner,total, sport=nfl,baseball. The full filter list is in the reference.

Read a row

One row is one game. Each listing is that game on one venue, with the venue's own ID and a ready-made request you can call as-is. Real row, trimmed:

{
  "id": "ev:nfl:cleveland-browns:pittsburgh-steelers:2026-10-02",
  "sport": "nfl",
  "league": "NFL",
  "name": "Pittsburgh Steelers vs Cleveland Browns",
  "teams": ["Pittsburgh Steelers", "Cleveland Browns"],
  "start": "2026-10-02T00:15:00.000Z",
  "status": "scheduled",
  "listings": [
    {
      "venue": "kalshi",
      "marketId": "KXNFLGAME-26OCT01PITCLE-PIT",
      "type": "winner",
      "tier": "split-merge",
      "confidence": 1,
      "request": {
        "method": "GET",
        "url": "https://external-api.kalshi.com/trade-api/v2/markets/KXNFLGAME-26OCT01PITCLE-PIT"
      }
    },
    {
      "venue": "poly",
      "marketId": "aec-nfl-pit-cle-2026-10-01",
      "type": "winner",
      "tier": "exact",
      "confidence": 1,
      "request": {
        "method": "GET",
        "url": "https://gateway.polymarket.us/v1/market/slug/aec-nfl-pit-cle-2026-10-01"
      }
    },
    {
      "venue": "predictfun",
      "marketId": "1607342",
      "type": "winner",
      "tier": "exact",
      "confidence": 1,
      "request": {
        "method": "GET",
        "url": "https://api.predict.fun/v1/markets/1607342",
        "auth": "x-api-key"
      }
    }
  ],
  "markets": [ ... ],
  "notes": { "poly": "tie settles 0.50" },
  "seq": 2953883
}

Use id as your key for the game. markets groups every bet type (winner, totals, spreads) with its own per-venue listings, and the line is part of the match, so over 45.5 is never mixed with over 48.5.

Stay current

Every response carries a seq number. Save it, then ask only for what changed:

curl -H "x-api-key: YOUR_KEY" \
  "https://api.matchwire.win/api/v1/rows?sport=nfl&since=SEQ"

Changed games come back whole. Games that are gone come back as {"id": "...", "deleted": true}: remove them. Prefer a stream? GET /api/v1/push sends the same updates as they happen.

Make one full call, save the top-level seq, then poll /rows?since=SEQ and save each new seq. Changed games come back whole; removed games come back in tombstones as {"id": "...", "deleted": true}. When you filter by venue or type, a game that no longer matches your filter also comes back as deleted. Do not re-pull the full set on a timer.

Hand it to your AI

Paste this into ChatGPT, Claude or any coding AI, with your key in place of MY_KEY:

You have access to the matchwire API at https://api.matchwire.win.
Send header "x-api-key: MY_KEY" on every call.
It returns one row per game, matched across Kalshi, Polymarket US,
Polymarket International and Predict.fun. Rows hold mapping only, no prices.

1. First call: GET /api/v1/rows (add ?sport=, ?venue=, ?type= to narrow it).
   Save the "seq" number from the response.
2. After that, call GET /api/v1/rows?since=SEQ to get only what changed,
   then save the new "seq". Rows with "deleted": true are gone: remove them.
3. Use each row's "id" as the game's key. Never match games by title yourself.
4. Each listing has "request": call that URL as-is to reach the market on
   that venue. If it says "auth": "x-api-key", send my own key for that venue.
5. A 403 means the ask is outside my plan; the response says what is allowed.

Full reference: https://matchwire.win/docs/  and  https://matchwire.win/llms.txt

Before you integrate anything, explain in plain English what you plan to do, and ask me any questions you need so this works well. Then offer to demonstrate it by pulling one match for me and confirming it works.

Endpoints

Filters

Add any of these to /rows. Lists are comma separated; filters combine.

Venue names: kalshi, poly (Polymarket US), polyintl (Polymarket International), predictfun. The live stream accepts sport, venue and type.

The row

A listing

matchwire serves mapping only: no prices or order books. Use request to read those from the venue itself.

Errors and limits

Agents: the MCP server is live at POST /mcp. Plans: pricing. Plain-text reference for AIs: llms.txt.