diff --git a/new_tests/test_message_history.py b/new_tests/test_message_history.py
new file mode 100644
index 0000000..725a8c5
--- /dev/null
+++ b/new_tests/test_message_history.py
@@ -0,0 +1,950 @@
+import time
+import inspect
+import functools
+import socketio
+import pytest
+
+
+def _mk_server():
+    """Basic in-memory server suitable for unit tests."""
+    return socketio.Server(async_mode="threading")
+
+
+# ---------- Discovery and adaptation helpers ----------
+
+def _iter_callables(obj, max_depth=3):
+    """Yield (owner, name, callable) by recursively scanning attributes up to max_depth."""
+    seen = set()
+
+    def walk(target, depth):
+        if depth > max_depth:
+            return
+        for name in dir(target):
+            if name.startswith("_"):
+                continue
+            try:
+                cand = getattr(target, name, None)
+            except Exception:
+                continue
+            if callable(cand):
+                key = (id(target), name)
+                if key not in seen:
+                    seen.add(key)
+                    yield (target, name, cand)
+            if cand is None or callable(cand):
+                continue
+            try:
+                yield from walk(cand, depth + 1)
+            except Exception:
+                continue
+
+    yield from walk(obj, 0)
+
+
+def _find_callable(obj, predicate):
+    """Find first callable matching predicate."""
+    for owner, name, fn in _iter_callables(obj):
+        if predicate(name, fn):
+            return name, fn
+    return None, None
+
+
+def _has_roomish_param(fn):
+    """Check if function has a room-like parameter."""
+    try:
+        sig = inspect.signature(fn)
+    except (TypeError, ValueError):
+        return False
+    pnames = set(sig.parameters.keys())
+    # Only use aliases from the spec
+    return _pick_alias(pnames, ["room", "room_id", "room_name"]) is not None
+
+
+def _pick_alias(param_names, aliases):
+    """Return the first alias that exists in param_names, else None."""
+    for a in aliases:
+        if a in param_names:
+            return a
+    return None
+
+
+def _wrap_kwargs(fn, semantic_kwargs=True):
+    """Build a wrapper for fn that accepts semantic kwargs using spec-defined aliases."""
+    sig = inspect.signature(fn)
+    params = set(sig.parameters.keys())
+    # Only aliases from the spec
+    alias_map = {
+        "room": ["room", "room_id", "room_name"],
+        "limit": ["limit", "n", "count", "max_items"],
+        "namespace": ["namespace", "ns"],
+        "include_events": ["include_events", "include", "events_include"],
+        "exclude_events": ["exclude_events", "exclude", "events_exclude"],
+        "payload_size_cap": ["payload_size_cap", "cap", "size_cap"],
+        "enabled": ["enabled", "enable", "on"],
+        "max_entries": ["max_entries", "max", "limit"],
+        "retention_seconds": ["retention_seconds", "retention", "ttl"],
+    }
+
+    def map_kwargs(kwargs):
+        mapped = {}
+        for sem_key, value in kwargs.items():
+            aliases = alias_map.get(sem_key, [sem_key])
+            chosen = _pick_alias(params, aliases)
+            if chosen is not None:
+                mapped[chosen] = value
+        return mapped
+
+    @functools.wraps(fn)
+    def wrapper(**kwargs):
+        return fn(**map_kwargs(kwargs))
+
+    return wrapper
+
+
+def discover_get_history(sio):
+    """Find the best matching fetch method by scoring candidates."""
+    candidates = []
+    for owner, name, fn in _iter_callables(sio):
+        lname = name.lower()
+        try:
+            sig = inspect.signature(fn)
+            pnames = set(sig.parameters.keys())
+        except (TypeError, ValueError):
+            continue
+
+        # Only use aliases from the spec
+        room_ok = _pick_alias(pnames, ["room", "room_id", "room_name"]) is not None
+        limit_ok = _pick_alias(pnames, ["limit", "n", "count", "max_items"]) is not None
+        any_opt = any(_pick_alias(pnames, alist) for alist in [
+            ["namespace", "ns"],
+            ["include_events", "include", "events_include"],
+            ["exclude_events", "exclude", "events_exclude"],
+            ["payload_size_cap", "cap", "size_cap"],
+        ])
+
+        has_fetch_get = any(k in lname for k in ["get", "fetch"]) or lname.startswith("list")
+        is_setter_like = any(k in lname for k in ["set", "configure", "update", "assign"]) and not ("get" in lname or "fetch" in lname)
+        has_history_hint = ("history" in lname) or ("recent" in lname) or ("buffer" in lname)
+
+        score = 0
+        if room_ok:
+            score += 2
+        if limit_ok:
+            score += 2
+        if any_opt:
+            score += 1
+        if has_fetch_get:
+            score += 1
+        if is_setter_like:
+            score -= 2
+        if has_history_hint:
+            score += 1
+
+        if room_ok and limit_ok:
+            candidates.append((score, name, fn))
+
+    assert candidates, "Missing a room history getter per spec."
+    candidates.sort(key=lambda t: (-t[0], t[1]))
+    _, _, best = candidates[0]
+    return _wrap_kwargs(best, semantic_kwargs=True)
+
+
+def discover_enable_disable_configure(sio):
+    """Return a tuple of wrappers: (enable_fn, disable_fn, configure_fn, enable_params_set)."""
+    def pred_enable(name, fn):
+        lname = name.lower()
+        return any(k in lname for k in ["enable", "on", "start", "activate", "set"]) and _has_roomish_param(fn)
+
+    def pred_disable(name, fn):
+        lname = name.lower()
+        return any(k in lname for k in ["disable", "off", "stop", "deactivate", "unset"]) and _has_roomish_param(fn)
+
+    def pred_config(name, fn):
+        lname = name.lower()
+        return any(k in lname for k in ["config", "configure", "set"]) and _has_roomish_param(fn)
+
+    _, e_fn = _find_callable(sio, pred_enable)
+    _, d_fn = _find_callable(sio, pred_disable)
+    _, c_fn = _find_callable(sio, pred_config)
+
+    e_wrap = _wrap_kwargs(e_fn, semantic_kwargs=True) if e_fn else None
+    d_wrap = _wrap_kwargs(d_fn, semantic_kwargs=True) if d_fn else None
+    c_wrap = _wrap_kwargs(c_fn, semantic_kwargs=True) if c_fn else None
+
+    enable_params_set = set()
+    if e_fn:
+        p = set(inspect.signature(e_fn).parameters.keys())
+        for sem, aliases in {
+            "namespace": ["namespace", "ns"],
+            "max_entries": ["max_entries", "max", "limit"],
+            "retention_seconds": ["retention_seconds", "retention", "ttl"],
+            "payload_size_cap": ["payload_size_cap", "cap", "size_cap"],
+            "enabled": ["enabled", "enable", "on"],
+        }.items():
+            if _pick_alias(p, aliases):
+                enable_params_set.add(sem)
+
+    return e_wrap, d_wrap, c_wrap, enable_params_set
+
+
+def discover_stats_getter(sio):
+    """Return (stats_fn_wrapper, fields_alias) or (None, None)."""
+    def pred(name, fn):
+        lname = name.lower()
+        return any(k in lname for k in ["stats", "metrics", "observability", "counters", "counts"])
+
+    _, fn = _find_callable(sio, pred)
+    if not fn:
+        return None, None
+
+    stats_wrap = _wrap_kwargs(fn, semantic_kwargs=True)
+    # Only aliases from the spec
+    fields_alias = {
+        "entries": ["entries_count", "entries", "count"],
+        "evict_size": ["evictions_size", "size_evictions", "evictions_by_size"],
+        "evict_time": ["evictions_time", "time_evictions", "evictions_by_time"],
+    }
+    return stats_wrap, fields_alias
+
+
+def pick_stat_keys(stats_dict, fields_alias):
+    """Pick actual keys from stats dict based on allowed aliases."""
+    picked = {}
+    for need, aliases in fields_alias.items():
+        for key in aliases:
+            if key in stats_dict:
+                picked[need] = key
+                break
+        assert need in picked, f"stats missing required semantic field: {need}"
+    return picked
+
+
+# ---------- Tests ----------
+
+def test_default_disabled_is_required_with_enable_path():
+    """History must be disabled by default and require explicit enablement."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    assert enable_fn or configure_fn, (
+        "Spec requires per-room enablement."
+    )
+
+    hist = get_history(room="__t:default_disabled__", limit=10, namespace="/")
+    assert isinstance(hist, list)
+    assert hist == [], "History must be empty before enabling."
+
+    sio.emit("x_disabled", 1, room="__t:default_disabled__", namespace="/")
+    hist2 = get_history(room="__t:default_disabled__", limit=10, namespace="/")
+    assert hist2 == []
+
+
+def test_ordering_and_schema_after_enable():
+    """After enabling, messages should be recorded with correct schema and ordering."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:order__"
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        if "max_entries" in enable_params:
+            kwargs["max_entries"] = 50
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+        if max_key:
+            kwargs[max_key] = 50
+        configure_fn(**kwargs)
+
+    sio.emit("message", {"text": "hello"}, room=room)
+    time.sleep(0.01)
+    sio.emit("message", {"text": "world"}, room=room)
+    time.sleep(0.01)
+    sio.emit("message", {"text": "!"}, room=room)
+
+    hist = get_history(room=room, limit=2, namespace="/")
+    assert isinstance(hist, list)
+    assert len(hist) == 2
+    assert [e["data"]["text"] for e in hist] == ["world", "!"]
+
+    now = time.time()
+    for e in hist:
+        assert "event" in e and "data" in e and "timestamp" in e
+        assert isinstance(e["timestamp"], float)
+        assert now - 24 * 3600 <= e["timestamp"] <= now + 5
+
+
+def test_include_only_and_exclude_only_filters_required():
+    """Include and exclude filters must work correctly."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:filters__"
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    sio.emit("state", {"v": 1}, room=room)
+    sio.emit("info", {"v": 2}, room=room)
+    sio.emit("other", {"v": 3}, room=room)
+
+    inc = get_history(
+        room=room, limit=10, namespace="/",
+        include_events=["state", "info"], exclude_events=None, payload_size_cap=None
+    )
+    assert all(h["event"] in {"state", "info"} for h in inc)
+
+    exc = get_history(
+        room=room, limit=10, namespace="/",
+        include_events=None, exclude_events=["info"], payload_size_cap=None
+    )
+    assert all(h["event"] != "info" for h in exc)
+
+    both = get_history(
+        room=room, limit=10, namespace="/",
+        include_events=("state", "info"), exclude_events={"info"}, payload_size_cap=None
+    )
+    assert all(h["event"] in {"state", "info"} for h in both)
+    assert all(h["event"] != "info" for h in both)
+
+def test_stats_getter_is_per_room():
+    """Stats getter must accept room parameter and return room-specific stats."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    stats_fn, fields_alias = discover_stats_getter(sio)
+    assert stats_fn is not None, "Spec requires stats getter"
+
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    r1, r2 = "__t:stats_room:1__", "__t:stats_room:2__"
+
+    # Enable both rooms
+    if enable_fn:
+        kwargs = {}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        if "max_entries" in enable_params:
+            kwargs["max_entries"] = 10
+        enable_fn(room=r1, **kwargs)
+        enable_fn(room=r2, **kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        base = {"enabled": True}
+        if "namespace" in cfg_sig:
+            base["namespace"] = "/"
+        max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+        if max_key:
+            base[max_key] = 10
+        configure_fn(room=r1, **base)
+        configure_fn(room=r2, **base)
+
+    # Emit different counts to each room
+    sio.emit("a", 1, room=r1)
+    sio.emit("a", 2, room=r1)
+    sio.emit("a", 3, room=r1)
+    sio.emit("b", 1, room=r2)
+
+    # Stats should be per-room, not global
+    s1 = stats_fn(room=r1, namespace="/")
+    s2 = stats_fn(room=r2, namespace="/")
+
+    keys1 = pick_stat_keys(s1, fields_alias)
+    keys2 = pick_stat_keys(s2, fields_alias)
+
+    # Room 1 has 3 entries, Room 2 has 1
+    assert s1[keys1["entries"]] == 3, "Stats must be per-room"
+    assert s2[keys2["entries"]] == 1, "Stats must be per-room"
+
+def test_size_eviction_required():
+    """Size-based eviction must work correctly (required feature)."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room1 = "__t:evict:size__"
+
+    if enable_fn:
+        kwargs = {"room": room1}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        if "max_entries" in enable_params:
+            kwargs["max_entries"] = 2
+            enable_fn(**kwargs)
+        else:
+            enable_fn(**kwargs)
+            if configure_fn:
+                cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+                max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+                if max_key:
+                    cfg_kwargs = {"room": room1, "enabled": True, max_key: 2}
+                    if "namespace" in cfg_sig:
+                        cfg_kwargs["namespace"] = "/"
+                    configure_fn(**cfg_kwargs)
+                else:
+                    pytest.fail("Spec requires a size cap knob; none discovered")
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+        assert max_key is not None, "Spec requires a size cap knob"
+        cfg_kwargs = {"room": room1, "enabled": True, max_key: 2}
+        if "namespace" in cfg_sig:
+            cfg_kwargs["namespace"] = "/"
+        configure_fn(**cfg_kwargs)
+
+    for i in range(5):
+        sio.emit("message", {"i": i}, room=room1)
+
+    h1 = get_history(room=room1, limit=10, namespace="/")
+    assert [e["data"]["i"] for e in h1] == [3, 4]
+
+def test_api_requirements_accessible_on_server():
+    """Required methods must be accessible directly on socketio.Server."""
+    sio = _mk_server()
+    
+    assert hasattr(sio, 'enable_history') and callable(getattr(sio, 'enable_history'))
+    assert hasattr(sio, 'disable_history') and callable(getattr(sio, 'disable_history'))  
+    assert hasattr(sio, 'get_history') and callable(getattr(sio, 'get_history'))
+    assert hasattr(sio, 'get_history_stats') and callable(getattr(sio, 'get_history_stats'))
+    
+    sig_enable = inspect.signature(sio.enable_history)
+    assert 'room' in sig_enable.parameters
+    
+    sig_disable = inspect.signature(sio.disable_history)  
+    assert 'room' in sig_disable.parameters
+    
+    sig_get = inspect.signature(sio.get_history)
+    assert 'room' in sig_get.parameters
+    assert 'limit' in sig_get.parameters
+    
+    sig_stats = inspect.signature(sio.get_history_stats)
+    assert 'room' in sig_stats.parameters
+
+def test_filter_ordering_include_then_exclude():
+    """When both filters provided, include must be applied first, then exclude."""
+    sio = _mk_server()
+    
+    room = "__t:filter_order__"
+    sio.enable_history(room=room)
+    
+    sio.emit("A", {"val": 1}, room=room)
+    sio.emit("B", {"val": 2}, room=room)
+    sio.emit("C", {"val": 3}, room=room)
+    sio.emit("D", {"val": 4}, room=room)
+    
+    result = sio.get_history(
+        room=room, limit=10,
+        include_events=["A", "B"],
+        exclude_events=["B", "D"]
+    )
+    
+    events = [e["event"] for e in result]
+    assert "A" in events, "A should be included"
+    assert "B" not in events, "B should be excluded (after being included)"
+    assert "C" not in events, "C should not be included"
+    assert "D" not in events, "D should be excluded"
+    assert len(events) == 1, "Only event A should remain"
+
+    result2 = sio.get_history(
+        room=room, limit=10,
+        include_events=["B"], 
+        exclude_events=["B"]
+    )
+    assert len(result2) == 0, "Include must be applied first, then exclude"
+
+def test_time_retention_optional():
+    """Time-based eviction (optional feature per spec)."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room2 = "__t:evict:time__"
+
+    # Check if TTL is supported
+    ttl_supported = False
+    ret_key = None
+
+    if enable_fn and "retention_seconds" in enable_params:
+        ttl_supported = True
+    elif configure_fn:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        ret_key = _pick_alias(cfg_sig, ["retention_seconds", "retention", "ttl"])
+        if ret_key:
+            ttl_supported = True
+
+    if not ttl_supported:
+        pytest.skip("Time-based expiry is optional per spec; not supported by this implementation")
+
+    if enable_fn and "retention_seconds" in enable_params:
+        kwargs = {"room": room2, "retention_seconds": 0.5}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        ret_key = _pick_alias(cfg_sig, ["retention_seconds", "retention", "ttl"])
+        cfg_kwargs = {"room": room2, "enabled": True, ret_key: 0.5}
+        if "namespace" in cfg_sig:
+            cfg_kwargs["namespace"] = "/"
+        configure_fn(**cfg_kwargs)
+
+    sio.emit("m", {"x": 1}, room=room2)
+    time.sleep(0.7)
+    h2 = get_history(room=room2, limit=10, namespace="/")
+    assert h2 == []
+
+
+def test_namespace_isolation_using_fetch_namespace():
+    """History must be isolated by namespace."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:ns__"
+    ns1 = "/"
+    ns2 = "/admin"
+
+    if enable_fn:
+        if "namespace" in enable_params:
+            enable_fn(room=room, namespace=ns1)
+            enable_fn(room=room, namespace=ns2)
+        else:
+            enable_fn(room=room)
+    elif configure_fn:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        if "namespace" in cfg_sig:
+            configure_fn(room=room, enabled=True, namespace=ns1)
+            configure_fn(room=room, enabled=True, namespace=ns2)
+        else:
+            configure_fn(room=room, enabled=True)
+
+    sio.emit("e1", {"n": 1}, room=room, namespace=ns1)
+    sio.emit("e2", {"n": 2}, room=room, namespace=ns2)
+
+    h1 = get_history(room=room, limit=10, namespace=ns1)
+    h2 = get_history(room=room, limit=10, namespace=ns2)
+
+    assert any(e["event"] == "e1" for e in h1)
+    assert not any(e["event"] == "e2" for e in h1)
+    assert any(e["event"] == "e2" for e in h2)
+    assert not any(e["event"] == "e1" for e in h2)
+
+
+def test_limit_applies_after_filters_oldest_to_newest():
+    """Limit should apply after filtering, returning oldest-to-newest."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:filters_limit__"
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    for i in range(6):
+        sio.emit("state" if i % 2 == 0 else "info", {"i": i}, room=room)
+
+    hist = get_history(
+        room=room, limit=2, namespace="/",
+        include_events=["state"], exclude_events=None, payload_size_cap=None
+    )
+    assert len(hist) == 2
+    assert [e["data"]["i"] for e in hist] == [2, 4]
+
+
+def test_default_namespace_fallback_behaves_like_root():
+    """Omitting namespace should default to root namespace."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:ns_default__"
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    sio.emit("x", {"v": 1}, room=room)
+    h_no_ns = get_history(room=room, limit=10)
+    h_root = get_history(room=room, limit=10, namespace="/")
+    assert [e["event"] for e in h_no_ns] == [e["event"] for e in h_root]
+
+
+def test_enable_time_payload_cap_if_supported():
+    """Enable-time payload cap should apply when fetch-time cap is omitted (if supported)."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:cap_enable_only__"
+    long_txt = "abcdefghijklmnopqrstuvwxyz"
+
+    # Check if enable-time cap is supported
+    applied = False
+    if enable_fn and "payload_size_cap" in enable_params:
+        kwargs = {"room": room, "payload_size_cap": 5}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+        applied = True
+    elif configure_fn:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        cap_key = _pick_alias(cfg_sig, ["payload_size_cap", "cap", "size_cap"])
+        enabled_key = _pick_alias(cfg_sig, ["enabled", "enable", "on"])
+        if enabled_key and cap_key:
+            kwargs = {"room": room, enabled_key: True, cap_key: 5}
+            if "namespace" in cfg_sig:
+                kwargs["namespace"] = "/"
+            configure_fn(**kwargs)
+            applied = True
+
+    if not applied:
+        pytest.skip("Payload truncation is optional; not supported by this implementation")
+
+    sio.emit("text", long_txt, room=room)
+    hist = get_history(room=room, limit=10, namespace="/")
+    txt = next(e for e in hist if e["event"] == "text")["data"]
+    assert isinstance(txt, str) and len(txt) <= 5
+
+def test_payload_size_cap_at_fetch_time_if_supported():
+    """Payload size cap should truncate strings and bytes at fetch time (if supported)."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    # Check if fetch-time payload cap is supported
+    try:
+        sig = inspect.signature(get_history.__wrapped__)
+    except AttributeError:
+        sig = inspect.signature(get_history)
+    
+    params = set(sig.parameters.keys())
+    cap_param = _pick_alias(params, ["payload_size_cap", "cap", "size_cap"])
+    
+    if cap_param is None:
+        pytest.skip("Fetch-time payload truncation is optional; not supported by this implementation")
+
+    room = "__t:cap__"
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    sio.emit("text", "abcdefghij", room=room)
+    sio.emit("blob", b"ABCDEFGHIJ", room=room)
+
+    hist = get_history(
+        room=room, limit=10, namespace="/",
+        include_events=None, exclude_events=None, payload_size_cap=5
+    )
+    txt = next(e for e in hist if e["event"] == "text")["data"]
+    blob = next(e for e in hist if e["event"] == "blob")["data"]
+    assert txt == "abcde"
+    assert blob == b"ABCDE"
+
+
+def test_fetch_time_cap_precedence_if_both_supported():
+    """Fetch-time payload cap takes precedence over enable-time cap (if both supported)."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    # Check if fetch-time cap is supported
+    try:
+        sig = inspect.signature(get_history.__wrapped__)
+    except AttributeError:
+        sig = inspect.signature(get_history)
+    
+    params = set(sig.parameters.keys())
+    fetch_cap_param = _pick_alias(params, ["payload_size_cap", "cap", "size_cap"])
+    
+    if fetch_cap_param is None:
+        pytest.skip("Fetch-time payload truncation is optional; not supported")
+
+    # Check if enable-time cap is supported
+    enable_cap_supported = False
+    if enable_fn and "payload_size_cap" in enable_params:
+        enable_cap_supported = True
+    elif configure_fn:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        if _pick_alias(cfg_sig, ["payload_size_cap", "cap", "size_cap"]):
+            enable_cap_supported = True
+    
+    if not enable_cap_supported:
+        pytest.skip("Enable-time payload cap not supported; cannot test precedence")
+
+    room = "__t:cap-precedence__"
+
+    # Set enable-time cap to 10
+    if enable_fn and "payload_size_cap" in enable_params:
+        kwargs = {"room": room, "payload_size_cap": 10}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        cap_key = _pick_alias(cfg_sig, ["payload_size_cap", "cap", "size_cap"])
+        kwargs = {"room": room, "enabled": True, cap_key: 10}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    sio.emit("text", "abcdefghij", room=room)
+    
+    # Fetch with smaller cap (5); should override enable-time cap (10)
+    hist = get_history(room=room, limit=10, namespace="/", payload_size_cap=5)
+    txt = next(e for e in hist if e["event"] == "text")["data"]
+    assert txt == "abcde", "Fetch-time cap should take precedence"
+
+def test_cross_room_isolation_same_namespace():
+    """Different rooms in same namespace must have isolated history."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    r1, r2 = "__t:rooms:1__", "__t:rooms:2__"
+
+    if enable_fn:
+        kwargs = {}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(room=r1, **kwargs)
+        enable_fn(room=r2, **kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        base = {"enabled": True}
+        if "namespace" in cfg_sig:
+            base["namespace"] = "/"
+        configure_fn(room=r1, **base)
+        configure_fn(room=r2, **base)
+
+    sio.emit("a", 1, room=r1)
+    sio.emit("b", 2, room=r2)
+
+    h1 = get_history(room=r1, limit=10, namespace="/")
+    h2 = get_history(room=r2, limit=10, namespace="/")
+
+    assert any(e["event"] == "a" for e in h1)
+    assert not any(e["event"] == "b" for e in h1)
+    assert any(e["event"] == "b" for e in h2)
+    assert not any(e["event"] == "a" for e in h2)
+
+
+def test_stats_required_with_size_eviction():
+    """Stats getter must return required fields with size eviction tracking."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    stats_fn, fields_alias = discover_stats_getter(sio)
+    assert stats_fn is not None, "Spec requires basic stats for observability"
+
+    enable_fn, _, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:stats__"
+
+    configured = False
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        if "max_entries" in enable_params:
+            kwargs["max_entries"] = 3
+        enable_fn(**kwargs)
+        configured = True
+
+        # Also try to configure via configure_fn if max_entries not in enable
+        if "max_entries" not in enable_params and configure_fn:
+            cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+            max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+            if max_key:
+                cfg_kwargs = {"room": room, "enabled": True, max_key: 3}
+                if "namespace" in cfg_sig:
+                    cfg_kwargs["namespace"] = "/"
+                try:
+                    configure_fn(**cfg_kwargs)
+                except TypeError:
+                    pass
+    elif configure_fn:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        cfg_kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            cfg_kwargs["namespace"] = "/"
+        max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+        assert max_key, "Spec requires size limit parameter"
+        cfg_kwargs[max_key] = 3
+        configure_fn(**cfg_kwargs)
+        configured = True
+
+    assert configured, "Spec requires per-room enable/configuration"
+
+    s0 = stats_fn(room=room, namespace="/")
+    assert isinstance(s0, dict)
+    keys = pick_stat_keys(s0, fields_alias)
+
+    sio.emit("a", 1, room=room)
+    sio.emit("b", 2, room=room)
+    sio.emit("c", 3, room=room)
+    sio.emit("d", 4, room=room)
+
+    s1 = stats_fn(room=room, namespace="/")
+    assert s1[keys["entries"]] >= 0
+    assert s1[keys["evict_size"]] >= s0[keys["evict_size"]]
+
+    for k in keys.values():
+        assert s1[k] >= 0
+
+
+def test_disable_stops_new_recordings_and_getter_returns_empty():
+    """Disabling history must stop recording and return empty list."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, disable_fn, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    assert enable_fn or configure_fn, "Spec requires a per-room enable/configure mechanism."
+    assert disable_fn or configure_fn, "Spec requires a way to disable."
+
+    room = "__t:disable:getter__"
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        if "max_entries" in enable_params:
+            kwargs["max_entries"] = 5
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        max_key = _pick_alias(cfg_sig, ["max_entries", "max", "limit"])
+        if max_key:
+            kwargs[max_key] = 5
+        configure_fn(**kwargs)
+
+    sio.emit("before", {"v": 1}, room=room)
+    assert len(get_history(room=room, limit=10, namespace="/")) >= 1
+
+    if disable_fn:
+        disable_fn(room=room, namespace="/")
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": False}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    sio.emit("after_disable", {"v": 2}, room=room)
+    assert get_history(room=room, limit=10, namespace="/") == []
+
+    if enable_fn:
+        kwargs = {"room": room}
+        if "namespace" in enable_params:
+            kwargs["namespace"] = "/"
+        enable_fn(**kwargs)
+    else:
+        cfg_sig = set(inspect.signature(configure_fn).parameters.keys())
+        kwargs = {"room": room, "enabled": True}
+        if "namespace" in cfg_sig:
+            kwargs["namespace"] = "/"
+        configure_fn(**kwargs)
+
+    sio.emit("after_reenable", {"v": 3}, room=room)
+    reh = get_history(room=room, limit=10, namespace="/")
+    assert any(e["event"] == "after_reenable" for e in reh)
+    assert not any(e["event"] == "after_disable" for e in reh), \
+        "Events emitted while disabled MUST NOT surface after re-enabling"
+
+
+def test_re_enable_starts_fresh():
+    """Re-enabling a room must start with empty history (no retained entries)."""
+    sio = _mk_server()
+    get_history = discover_get_history(sio)
+    enable_fn, disable_fn, configure_fn, enable_params = discover_enable_disable_configure(sio)
+
+    room = "__t:re_enable_fresh__"
+
+    # Enable and emit
+    if enable_fn:
+        enable_fn(room=room, namespace="/")
+    else:
+        configure_fn(room=room, enabled=True, namespace="/")
+
+    sio.emit("old_event", {"data": "old"}, room=room)
+    assert len(get_history(room=room, limit=10, namespace="/")) == 1
+
+    # Disable
+    if disable_fn:
+        disable_fn(room=room, namespace="/")
+    else:
+        configure_fn(room=room, enabled=False, namespace="/")
+
+    # Re-enable
+    if enable_fn:
+        enable_fn(room=room, namespace="/")
+    else:
+        configure_fn(room=room, enabled=True, namespace="/")
+
+    # History must be empty after re-enable
+    hist = get_history(room=room, limit=10, namespace="/")
+    assert hist == [], "Re-enabling must start with fresh history"
+
+    # New events should be recorded
+    sio.emit("new_event", {"data": "new"}, room=room)
+    hist = get_history(room=room, limit=10, namespace="/")
+    assert len(hist) == 1
+    assert hist[0]["event"] == "new_event"
+
+
+@pytest.mark.skip(reason="Non-functional: best-effort/non-blocking not reliably testable")
+def test_recording_is_best_effort_and_non_blocking():
+    """Placeholder for non-functional requirement."""
+    pass
+
+
+@pytest.mark.skip(reason="Non-functional: single-process/in-memory not verifiable in unit tests")
+def test_in_memory_single_process_only():
+    """Placeholder for non-functional requirement."""
+    pass
\ No newline at end of file
diff --git a/test.sh b/test.sh
new file mode 100755
index 0000000..a9834d1
--- /dev/null
+++ b/test.sh
@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Test runner for python-socketio repository
+# Usage:
+#   ./test.sh base   # run existing tests (should pass at base commit)
+#   ./test.sh new    # run only the newly added tests
+
+cmd_exists() {
+  command -v "$1" >/dev/null 2>&1
+}
+
+run_pytest() {
+  if cmd_exists pytest; then
+    pytest -q "$@"
+  else
+    python -m pytest -q "$@"
+  fi
+}
+
+# Ensure an argument is provided before entering case
+if [ $# -lt 1 ]; then
+  echo "Usage: ./test.sh {base|new}" >&2
+  exit 1
+fi
+
+case "$1" in
+  base)
+    # Run the repository's existing test suite only
+    if [ -d tests ]; then
+      run_pytest tests/
+    else
+      echo "ERROR: Base suite not found at ./tests/. Provide baseline tests or adjust runner." >&2
+      exit 2
+    fi
+    ;;
+  new)
+    if [ -f new_tests/test_message_history.py ]; then
+      run_pytest new_tests/test_message_history.py
+    else
+      echo "ERROR: New test file not found: new_tests/test_message_history.py" >&2
+      exit 2
+    fi
+    ;;
+  *)
+    echo "Usage: ./test.sh {base|new}" >&2
+    exit 1
+    ;;
+esac