diff --git a/cmd/mavend/decisiontrace_test.go b/cmd/mavend/decisiontrace_test.go
new file mode 100644
index 0000000..813d34f
--- /dev/null
+++ b/cmd/mavend/decisiontrace_test.go
@@ -0,0 +1,163 @@
+package main
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/kami/maven/internal/decision"
+	"github.com/kami/maven/internal/ipc"
+	"github.com/kami/maven/internal/memory"
+	"github.com/kami/maven/internal/router"
+	"github.com/kami/maven/internal/tool"
+	"github.com/kami/maven/internal/voice"
+)
+
+// traceHandler — a handler with the decision ring wired, the same shape the
+// daemon builds in wireVoice.
+func traceHandler(t *testing.T, ring *decision.Ring) *reactiveHandler {
+	t.Helper()
+	st := newTestStore(t)
+	api := ipc.NewStoreAPI(st)
+	now := time.Now()
+	emb := router.NewHashEmbedder(1024)
+	return &reactiveHandler{
+		api:       api,
+		recall:    recallWiring{embedder: emb, memStore: memory.NewInMemoryStore()},
+		router:    buildRouter(emb, tool.NewMatcher(api), 0.55, nil),
+		replier:   voice.NewStubReplier(),
+		now:       func() time.Time { return now },
+		dataStore: st,
+		decisions: ring,
+	}
+}
+
+// findClaim — the first claim for a claimant, or nil.
+func findClaim(rec *decision.Record, claimant string) *decision.Claim {
+	for i := range rec.Claims {
+		if rec.Claims[i].Claimant == claimant {
+			return &rec.Claims[i]
+		}
+	}
+	return nil
+}
+
+// TestTurnRecordNamesWinnerAndLosers — the point of V-564. A turn a stage-0
+// grammar claims must leave a record naming that grammar as the winner, naming
+// a pre-route resolver that declined, and naming the routing engines that were
+// never reached at all. The last of those is the fact the hardcoded ordering
+// hides: "classifier" absent from the record and "classifier" never asked read
+// the same to a human, and only one of them is the truth.
+func TestTurnRecordNamesWinnerAndLosers(t *testing.T) {
+	ring := decision.NewRing()
+	h := traceHandler(t, ring)
+
+	reply := h.handleText(context.Background(), "web", "сколько сейчас времени")
+	if reply == "" {
+		t.Fatal("turn produced no reply")
+	}
+
+	recs := ring.Recent(5)
+	if len(recs) != 1 {
+		t.Fatalf("want 1 record, got %d", len(recs))
+	}
+	rec := recs[0]
+	if rec.Utterance != "сколько сейчас времени" {
+		t.Errorf("utterance = %q", rec.Utterance)
+	}
+	if !strings.HasPrefix(rec.Winner, "stage0:") {
+		t.Errorf("want a stage-0 grammar as the winner, got %q", rec.Winner)
+	}
+
+	// A loser that examined the turn: the confirm resolver ran first and had
+	// nothing pending.
+	confirm := findClaim(rec, "confirm")
+	if confirm == nil || confirm.Outcome != decision.Declined {
+		t.Errorf("confirm claim = %+v, want a decline", confirm)
+	}
+
+	// A loser that never looked: stage 0 answered, so neither routing engine
+	// was reached.
+	for _, name := range []string{"llm-router", "classifier"} {
+		c := findClaim(rec, name)
+		if c != nil && c.Outcome == decision.Won {
+			t.Errorf("%s cannot have won a stage-0 turn: %+v", name, c)
+		}
+	}
+
+	// And every rung of the ladder below the winner is named, not omitted.
+	for _, name := range preRouteLadder {
+		if findClaim(rec, name) == nil {
+			t.Errorf("ladder rung %q is missing from the record", name)
+		}
+	}
+}
+
+// TestRecordingDoesNotChangeTheReply — instrumentation, so a turn with the ring
+// wired and the same turn without it must answer identically. If this ever
+// fails, a claim site is doing more than noting.
+func TestRecordingDoesNotChangeTheReply(t *testing.T) {
+	for _, utt := range []string{
+		"сколько сейчас времени",
+		"запиши что я пил воду",
+		"что у меня сегодня",
+	} {
+		withRing := traceHandler(t, decision.NewRing()).handleText(context.Background(), "web", utt)
+		without := traceHandler(t, nil).handleText(context.Background(), "web", utt)
+		if withRing != without {
+			t.Errorf("%q: recorded reply %q != unrecorded %q", utt, withRing, without)
+		}
+	}
+}
+
+// TestQueryChainRecordsWhoWasNeverAsked — a query source below the claimant is
+// never consulted, and the record must say so rather than leave it out. This is
+// the arm that would have explained the Rome misroute in one read.
+func TestQueryChainRecordsWhoWasNeverAsked(t *testing.T) {
+	ring := decision.NewRing()
+	h := traceHandler(t, ring)
+	h.handleText(context.Background(), "web", "что у меня сегодня")
+
+	rec := ring.Recent(1)[0]
+	var asked, never int
+	for _, c := range rec.Claims {
+		if c.Stage != decision.StageQuery {
+			continue
+		}
+		if c.Outcome == decision.NeverAsked {
+			never++
+		} else {
+			asked++
+		}
+	}
+	if asked == 0 {
+		t.Fatal("no query source reported at all")
+	}
+	if never == 0 {
+		t.Fatal("no query source was recorded as never asked; the chain cannot have run to the end")
+	}
+	if got := len(querySourceNames()); asked+never != got {
+		t.Errorf("record covers %d of %d query sources", asked+never, got)
+	}
+}
+
+// TestTurnDecisionsFnConvertsTheRing — the IPC read path. Nil when voice was
+// never wired, because a box with no turns is an empty page and not an error.
+func TestTurnDecisionsFnConvertsTheRing(t *testing.T) {
+	if fn := turnDecisionsFn(nil); fn != nil {
+		t.Error("no wiring should mean no reader")
+	}
+	ring := decision.NewRing()
+	h := traceHandler(t, ring)
+	h.handleText(context.Background(), "web", "сколько сейчас времени")
+
+	fn := turnDecisionsFn(&voiceWiring{handler: h})
+	if fn == nil {
+		t.Fatal("wired handler produced no reader")
+	}
+	out := fn(10)
+	if len(out) != 1 || out[0].Winner == "" || len(out[0].Claims) == 0 {
+		t.Fatalf("conversion lost the record: %+v", out)
+	}
+}