diff --git a/fifa17-recon/tools/test_fut_contract.py b/fifa17-recon/tools/test_fut_contract.py
new file mode 100644
index 0000000..9bdb1fc
--- /dev/null
+++ b/fifa17-recon/tools/test_fut_contract.py
@@ -0,0 +1,136 @@
+#!/usr/bin/env python3
+"""Contract / freeze-safety regression tests for the FIFA 17 FUT backend.
+
+Hits the LIVE utas_server (default http://127.0.0.1:8099) and asserts each
+response matches the shape reversed from CardsDLL (see docs/ENDPOINT_MAP.md).
+The point is freeze-safety: FIFA's SAX deserializers hard-freeze (busy-loop at
+0x1801c7f1a) if a field that must be an array/object arrives as a scalar. These
+tests encode "must be array" / "must be object" / "must be number" per the
+reversed schemas so a future edit that reintroduces that class of bug fails here
+instead of freezing the game.
+
+Read-only: only GET endpoints are exercised (no pack buys / squad writes), so it
+never mutates the profile. Run:  python3 tools/test_fut_contract.py
+Exit 0 = all pass. No pytest dependency (stdlib only).
+"""
+import json, sys, urllib.request
+
+BASE = "http://127.0.0.1:8099"
+G = "/ut/game/fifa17"
+V2 = "/ut/v2/game/fifa17"
+
+_fail = []
+_pass = 0
+
+
+def _get(path):
+    with urllib.request.urlopen(BASE + path, timeout=5) as r:
+        raw = r.read()
+    return json.loads(raw) if raw else {}
+
+
+def check(name, cond, detail=""):
+    global _pass
+    if cond:
+        _pass += 1
+    else:
+        _fail.append(f"{name}: {detail}")
+
+
+def is_arr(x):  return isinstance(x, list)
+def is_obj(x):  return isinstance(x, dict)
+def is_num(x):  return isinstance(x, (int, float)) and not isinstance(x, bool)
+def is_str(x):  return isinstance(x, str)
+
+
+def test_credits():
+    d = _get(G + "/user/credits")
+    # coin counter binds to currencies[name==coins].funds (deser 0x180122c50), NOT "credits"
+    check("credits.currencies is array", is_arr(d.get("currencies")), repr(d.get("currencies")))
+    coins = next((c for c in d.get("currencies", []) if c.get("name") == "coins"), None)
+    check("credits has coins currency", coins is not None)
+    if coins:
+        check("coins.funds is number", is_num(coins.get("funds")), repr(coins.get("funds")))
+
+
+def test_v2_store_gate():
+    d = _get(V2 + "/store")
+    # FutStorePackQuantities eligibility gate (deser 0x1801758c0): result must be SUCCESS
+    check("v2/store result == SUCCESS", d.get("result") == "SUCCESS", repr(d))
+
+
+def test_store_catalog():
+    d = _get(G + "/store/purchasegroup/all")
+    # FutStoreGetPackTypes (deser 0x1801234e0): root key "purchase" MUST be an array
+    check("catalog.purchase is array", is_arr(d.get("purchase")), repr(type(d.get("purchase"))))
+    for p in d.get("purchase", []):
+        check("pack has assetId (real identity)", "assetId" in p, repr(p.get("assetId")))
+        check("pack.currencies is array (coin price)", is_arr(p.get("currencies")))
+        check("pack.packContentInfo is object", is_obj(p.get("packContentInfo")))
+        check("pack.extPrice is object", is_obj(p.get("extPrice")))
+        ep = p.get("extPrice", {})
+        check("extPrice.finalPrice is object", is_obj(ep.get("finalPrice")))
+
+
+def test_market_bodies():
+    # Shared IS-list body (deser 0x18013e7f0): auctionInfo MUST be array, credits number
+    for path in [G + "/auctionhouse?type=player&start=0&num=21",
+                 G + "/tradePile", G + "/watchList", G + "/trade/123"]:
+        d = _get(path)
+        check(f"{path} auctionInfo is array", is_arr(d.get("auctionInfo")), repr(d.get("auctionInfo")))
+        check(f"{path} credits is number", is_num(d.get("credits")), repr(d.get("credits")))
+    dup = _get(G + "/auctionhouse?type=player").get("duplicateItemIdList")
+    check("auctionhouse duplicateItemIdList is array", is_arr(dup), repr(dup))
+    md = _get(G + "/marketdata?defId=1")
+    check("marketdata minPrice is number", is_num(md.get("minPrice")))
+    check("marketdata maxPrice is number", is_num(md.get("maxPrice")))
+
+
+def test_squad_boot():
+    # LoadActiveSquad (deser 0x18013d1f0): players MUST be array; empty body would reset
+    # the 23 slots. formation is a string. This is the boot-critical path.
+    d = _get(G + "/squad/0")
+    check("squad.players is array", is_arr(d.get("players")), repr(type(d.get("players"))))
+    check("squad.formation is string", is_str(d.get("formation")), repr(d.get("formation")))
+    for pl in d.get("players", []):
+        # Empty bench/reserve slots legitimately carry itemData=null (proven-safe,
+        # matches the working in-game squad). Only a PRESENT itemData must be an
+        # object -- a scalar there would desync the reader.
+        it = pl.get("itemData")
+        check("squad slot itemData is object-or-null", it is None or is_obj(it), repr(it))
+
+
+def test_massinfo_empty():
+    # GetUserMassInfo (deser 0x180174630) MUST stay {} -- any populated userInfo/squad
+    # desyncs the parser -> freeze (CARD_SYSTEM.md). Guard against accidental population.
+    d = _get(G + "/userMassInfo")
+    check("userMassInfo is empty {}", d == {}, repr(d))
+
+
+def test_club_items():
+    # /club serves {"itemData":[...]} (SKIP'd by GetClubInfo, but must stay array-safe)
+    d = _get(G + "/club?type=player&count=5")
+    check("club.itemData is array", is_arr(d.get("itemData")), repr(type(d.get("itemData"))))
+
+
+def main():
+    tests = [test_credits, test_v2_store_gate, test_store_catalog, test_market_bodies,
+             test_squad_boot, test_massinfo_empty, test_club_items]
+    try:
+        _get(G + "/user/credits")
+    except Exception as e:
+        print(f"SERVER NOT REACHABLE at {BASE}: {e}\nStart it: python3 tools/utas_server.py")
+        return 2
+    for t in tests:
+        try:
+            t()
+        except Exception as e:
+            _fail.append(f"{t.__name__} raised {type(e).__name__}: {e}")
+    print(f"\n{_pass} checks passed, {len(_fail)} failed")
+    for f in _fail:
+        print("  FAIL:", f)
+    return 0 if not _fail else 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())