Answer "что я обычно делаю по вторникам?" by counting, not guessing (#254)

Behavioural memory, narrowed on purpose. internal/memory/behavior.go builds a
profile out of self-facts — distinct days per weekday, median time of day — and
reads it back in RU; router.ParseHabitQuery finds the weekday deterministically;
a `habits` query source answers the question.

Three things the plan doc asks for are deliberately absent, and the doc now
records why:

- The profile is COUNTED, not LLM-generated. A 1.7B asked to summarise a year of
  habits writes fluent claims about the owner's life that no row supports, and a
  wrong claim about him is the most expensive kind of wrong maven can be.
- No cached profile fact, so no "update on fact write" machinery. It is
  recomputed on the question; a cache that can disagree with its own rows is two
  truths.
- No proactive daily plan nudge. A dispatcher proposal at 08:00 every day is the
  definition of a nag. The path from "she noticed a pattern" to "she acts on it"
  already exists in internal/pattern with the proposal queue on /routines, and it
  goes through him.

A one-off is not a habit: an activity needs two distinct days before she will
call it usual, and until then she says she does not know yet. Only self-facts
count — env rows are the world, config rows are her own tuning state. The typical
time is a median so one 03:00 outlier cannot move a morning habit into the night.
An unrecognised fact key is read back verbatim rather than glossed into something
she made up.

The source sits before "calendar" in querySources, and its matcher requires a
habit marker, so "что я делаю в среду?" still reaches the calendar — answering a
question about this coming Wednesday with a statistical average would be
answering a different question.

Verified: make build and make test both exit 0.

cmd/mavend/actions_query.go

@@ -51,6 +51,11 @@ var querySources = []querySource{
 	// the more specific ask (its matcher requires a plan word), so the calendar
 	// listing would otherwise swallow it.
 	{"day-plan", (*reactiveHandler).queryDayPlan},
+	// Also before "calendar": "что я обычно делаю по средам?" names a weekday,
+	// and the habit question is the more specific one. Its matcher requires a
+	// habit marker ("обычно", "каждый", …), so a question about this coming
+	// Wednesday still reaches the calendar.
+	{"habits", (*reactiveHandler).queryHabits},
 	{"calendar", (*reactiveHandler).queryCalendar},
 	{"weather", (*reactiveHandler).queryWeather},
 	{"embed", (*reactiveHandler).queryEmbed},
@@ -135,6 +140,35 @@ func isRestOfDayQuery(text string) bool {
 	return strings.Contains(s, "дальше") || strings.Contains(s, "next")
 }
 
+// habitFactWindow — how many recent facts the behaviour profile is counted
+// over. Enough for a season of habits without scanning the whole store on every
+// question; the profile is recomputed on read, so the bound is the cost control.
+const habitFactWindow = 2000
+
+// queryHabits — "что я обычно делаю по вторникам?" (Vikunja #254). Counts the
+// answer out of the fact log rather than asking the model to summarise a life:
+// see internal/memory/behavior.go for why nothing here is generated.
+func (h *reactiveHandler) queryHabits(ctx context.Context, t *queryTurn) (string, bool) {
+	q, ok := router.ParseHabitQuery(t.dec.Utterance)
+	if !ok {
+		return "", false
+	}
+	facts, err := h.api.RecentFacts(ctx, habitFactWindow)
+	if err != nil {
+		log.Printf("voice: habits: recent facts: %v", err)
+		return "не получилось посмотреть записи.", true
+	}
+	obs := make([]memory.Observation, 0, len(facts))
+	for _, f := range facts {
+		obs = append(obs, memory.Observation{At: f.Ts, Key: f.Key, Kind: f.Kind})
+	}
+	profile := memory.BuildProfile(obs, h.now())
+	if q.HasWeekday {
+		return profile.FormatWeekdayRU(q.Weekday), true
+	}
+	return profile.FormatOverallRU(), true
+}
+
 // queryCalendar — "что у меня сегодня?", "планы на завтра?"
 // h.now(), not time.Now(): the handler's clock is the injected one, so this
 // source can be tested at a fixed time like the rest.

cmd/mavend/dayplan_test.go

@@ -141,3 +141,87 @@ func TestDayPlanSourcePrecedesCalendar(t *testing.T) {
 		t.Errorf("day-plan at %d must come before calendar at %d", plan, cal)
 	}
 }
+
+// habitAPI answers only RecentFacts — the whole input the behaviour profile
+// needs (Vikunja #254). Nothing is asked of the LLM, so nothing else is wired.
+type habitAPI struct {
+	ipc.UnimplementedCoreAPI
+	facts []ipc.Fact
+	err   error
+	calls int
+}
+
+func (a *habitAPI) RecentFacts(_ context.Context, _ int) ([]ipc.Fact, error) {
+	a.calls++
+	return a.facts, a.err
+}
+
+// tuesdayFacts — n weekly Tuesday rows for key, ending before now.
+func tuesdayFacts(key string, hh, weeks int, now time.Time) []ipc.Fact {
+	d := now
+	for d.Weekday() != time.Tuesday {
+		d = d.AddDate(0, 0, -1)
+	}
+	var out []ipc.Fact
+	for i := 0; i < weeks; i++ {
+		day := d.AddDate(0, 0, -7*i)
+		out = append(out, ipc.Fact{
+			Ts:   time.Date(day.Year(), day.Month(), day.Day(), hh, 0, 0, 0, now.Location()),
+			Kind: "self",
+			Key:  key,
+		})
+	}
+	return out
+}
+
+func TestQueryHabitsAnswersFromCountedFacts(t *testing.T) {
+	now := planDay() // a Monday
+	api := &habitAPI{facts: tuesdayFacts("workout", 19, 4, now)}
+	h := &reactiveHandler{api: api, now: func() time.Time { return now }}
+
+	reply, ok := h.queryHabits(context.Background(), &queryTurn{
+		dec: router.Decision{Intent: router.IntentQuery, Utterance: "что я обычно делаю по вторникам?"},
+	})
+	if !ok {
+		t.Fatal("the habit source must claim a habit question")
+	}
+	if want := "по вторникам ты обычно тренируешься около 19:00."; reply != want {
+		t.Errorf("reply = %q, want %q", reply, want)
+	}
+}
+
+func TestQueryHabitsPassesOnEverythingElse(t *testing.T) {
+	now := planDay()
+	for _, q := range []string{"что я делаю в среду?", "что у меня сегодня?", "какие планы на сегодня?", ""} {
+		api := &habitAPI{}
+		h := &reactiveHandler{api: api, now: func() time.Time { return now }}
+		if reply, ok := h.queryHabits(context.Background(), &queryTurn{
+			dec: router.Decision{Intent: router.IntentQuery, Utterance: q},
+		}); ok {
+			t.Errorf("%q was claimed by the habit source (reply %q)", q, reply)
+		}
+		if api.calls != 0 {
+			t.Errorf("%q scanned the fact log for a profile it does not want", q)
+		}
+	}
+}
+
+// Both specific sources must precede the calendar listing, which matches any
+// utterance naming a day.
+func TestHabitSourcePrecedesCalendar(t *testing.T) {
+	habits, cal := -1, -1
+	for i, s := range querySources {
+		switch s.name {
+		case "habits":
+			habits = i
+		case "calendar":
+			cal = i
+		}
+	}
+	if habits < 0 || cal < 0 {
+		t.Fatalf("sources missing: habits=%d calendar=%d", habits, cal)
+	}
+	if habits > cal {
+		t.Errorf("habits at %d must come before calendar at %d", habits, cal)
+	}
+}

docs/plans/09-behavioral-memory.md

@@ -27,3 +27,36 @@
 6. Wire voice query — `"что я обычно делаю?"` routes to `IntentQuery` → behavior profile lookup → LLM-phrased answer
 7. Add IPC read method `MethodGetBehaviorProfile` so mavweb can display it on `/dash`
 8. Test with synthetic fact history — verify weekly schedule is correctly inferred
+
+---
+
+## Status (2026-08-01) — partially shipped, deliberately narrowed
+
+Shipped on `overnight/behavior-profile`:
+
+- `internal/memory/behavior.go` — `BuildProfile` counts habits per weekday out of
+  self-facts: distinct-day counts (`MinHabitDays = 2`), a median time-of-day, and
+  `FormatWeekdayRU` / `FormatOverallRU` for the spoken answer.
+- `internal/router/habit.go` — `ParseHabitQuery`, which requires a habit marker
+  ("обычно", "каждую", "привычки", …) and parses the weekday deterministically.
+- `cmd/mavend/actions_query.go` — a `habits` query source, so "что я обычно делаю
+  по вторникам?" is answered.
+
+**Not shipped, and not to be shipped as written:**
+
+- *Step 3, LLM-generated profile stored as a fact.* The profile is COUNTED, not
+  generated. A 1.7B asked to summarise a year of habits produces fluent claims
+  about the owner's life that no row supports, and a wrong claim about him is the
+  most expensive kind of wrong maven can be. Counting is verifiable and cheap.
+- *Step 5, incremental updates on fact write.* There is no cache to keep fresh —
+  the profile is recomputed on the question, so a new fact is already in the next
+  answer. A cached profile that can disagree with its own rows is two truths.
+- *Step 4, proactive daily plan proposals via the dispatcher.* Maven is not a nag,
+  and a nudge at 08:00 every day proposing the day is the definition of one. The
+  sanctioned path from "she noticed a pattern" to "she acts on it" already exists:
+  `internal/pattern/detector.go` proposes a routine, and the owner accepts it on
+  `/routines`. It goes through him.
+
+Still open, if wanted later: `MethodGetBehaviorProfile` + a `/dash` panel (step 7).
+The counted profile needs no new IPC method to be *asked* about — the query source
+reads `RecentFacts` over the existing surface — so this is a display concern only.

internal/memory/behavior.go

@@ -0,0 +1,254 @@
+package memory
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+)
+
+// Behavioural memory — "what do I usually do?" (Vikunja #254).
+//
+// The profile is COUNTED, not generated. docs/plans/09-behavioral-memory.md
+// asks for an LLM to write a behaviour profile daily and store it as a fact;
+// this does not do that, on purpose. A 1.7B asked to summarise a year of habits
+// will produce fluent claims about the owner's life that no row in the store
+// supports, and a wrong claim about him is the most expensive kind of wrong
+// maven can be. Counting distinct days per weekday is verifiable, cheap enough
+// to run on the question, and cannot invent a habit he does not have.
+//
+// Recomputed on read rather than cached as a fact for the same reason the store
+// is append-only: a cached profile can disagree with the rows it came from, and
+// then there are two truths. The plan's step 5 ("profile updates on fact write")
+// exists to keep a cache fresh; there is no cache, so a new fact is already in
+// the next answer.
+//
+// It is also read-only and unprompted-free. The plan's step 4 — a morning
+// dispatcher nudge proposing the day — is deliberately NOT here: maven is not a
+// nag, and proposing plans at 08:00 every day is the definition of one. Pattern
+// inference that leads to a routine the owner accepts already exists in
+// internal/pattern with the proposal queue on /routines; that is the sanctioned
+// path from "she noticed" to "she acts", and it goes through him.
+
+// Observation — one thing the owner was recorded doing, reduced to what a habit
+// needs: when, and what. Facts arrive as store/ipc rows; the caller maps them
+// so this package stays free of both.
+type Observation struct {
+	At   time.Time
+	Key  string
+	Kind string // "self" | "env" | "config"
+}
+
+// Activity — one recurring thing, as counted. Days is the number of DISTINCT
+// days it was observed on, which is the number that decides whether something
+// is a habit; Count can be inflated by one busy day.
+//
+// TypicalAt is the median time of day it happens at, rounded to the minute — a
+// median and not a mean, so one 03:00 outlier does not move "он обычно пьёт
+// воду утром" into the night.
+type Activity struct {
+	Key       string
+	Days      int
+	Count     int
+	TypicalAt time.Duration
+}
+
+// Profile — the counted behaviour model. Weekly holds the activities that
+// recur on a given weekday, Overall the ones that recur at all.
+type Profile struct {
+	Since  time.Time
+	Until  time.Time
+	Weekly map[time.Weekday][]Activity
+	All    []Activity
+}
+
+// MinHabitDays — how many distinct days an activity must appear on before maven
+// will call it usual. Two is the smallest number that can distinguish a habit
+// from a one-off; below that she says she does not know yet, which is true.
+const MinHabitDays = 2
+
+// nonBehaviouralKeyPrefixes — keys that are machinery or one-shot records, not
+// behaviour. Calendar events carry the day in the key so they can never repeat;
+// cooldown and quiet rows are maven's own tuning state, not his habits.
+var nonBehaviouralKeyPrefixes = []string{
+	"calendar_event_",
+	"cooldown:",
+	"quiet",
+	"behavior_profile",
+}
+
+// BuildProfile counts habits out of observations. now bounds the window's upper
+// end and supplies the location every day boundary is taken in — a habit is
+// "on Tuesdays" in the owner's timezone or it is nothing.
+//
+// Only self-facts count. An env row is the world (weather, a relayed meeting),
+// and a config row is maven's own state; neither says anything about what he
+// usually does.
+func BuildProfile(obs []Observation, now time.Time) Profile {
+	loc := now.Location()
+	p := Profile{Until: now, Weekly: map[time.Weekday][]Activity{}}
+
+	type bucket struct {
+		days  map[string]struct{}
+		count int
+		mins  []int
+	}
+	// key → bucket, and (weekday, key) → bucket.
+	all := map[string]*bucket{}
+	weekly := map[time.Weekday]map[string]*bucket{}
+
+	for _, o := range obs {
+		if o.Kind != "self" {
+			continue
+		}
+		key := strings.TrimSpace(o.Key)
+		if key == "" || nonBehavioural(key) {
+			continue
+		}
+		at := o.At.In(loc)
+		if at.IsZero() || at.After(now) {
+			continue
+		}
+		if p.Since.IsZero() || at.Before(p.Since) {
+			p.Since = at
+		}
+		day := at.Format("2006-01-02")
+		minute := at.Hour()*60 + at.Minute()
+
+		bump := func(m map[string]*bucket) {
+			b := m[key]
+			if b == nil {
+				b = &bucket{days: map[string]struct{}{}}
+				m[key] = b
+			}
+			b.days[day] = struct{}{}
+			b.count++
+			b.mins = append(b.mins, minute)
+		}
+		bump(all)
+		wd := at.Weekday()
+		if weekly[wd] == nil {
+			weekly[wd] = map[string]*bucket{}
+		}
+		bump(weekly[wd])
+	}
+
+	harvest := func(m map[string]*bucket) []Activity {
+		var out []Activity
+		for key, b := range m {
+			if len(b.days) < MinHabitDays {
+				continue
+			}
+			out = append(out, Activity{
+				Key:       key,
+				Days:      len(b.days),
+				Count:     b.count,
+				TypicalAt: time.Duration(medianInt(b.mins)) * time.Minute,
+			})
+		}
+		// Most-established first, then earliest in the day, then by key so the
+		// same history always reads back the same way.
+		sort.Slice(out, func(i, j int) bool {
+			if out[i].Days != out[j].Days {
+				return out[i].Days > out[j].Days
+			}
+			if out[i].TypicalAt != out[j].TypicalAt {
+				return out[i].TypicalAt < out[j].TypicalAt
+			}
+			return out[i].Key < out[j].Key
+		})
+		return out
+	}
+
+	p.All = harvest(all)
+	for wd, m := range weekly {
+		if acts := harvest(m); len(acts) > 0 {
+			p.Weekly[wd] = acts
+		}
+	}
+	return p
+}
+
+func nonBehavioural(key string) bool {
+	for _, p := range nonBehaviouralKeyPrefixes {
+		if strings.HasPrefix(key, p) {
+			return true
+		}
+	}
+	return false
+}
+
+// medianInt — the middle value, averaging the two middles on an even count.
+func medianInt(xs []int) int {
+	if len(xs) == 0 {
+		return 0
+	}
+	s := make([]int, len(xs))
+	copy(s, xs)
+	sort.Ints(s)
+	mid := len(s) / 2
+	if len(s)%2 == 1 {
+		return s[mid]
+	}
+	return (s[mid-1] + s[mid]) / 2
+}
+
+// weekdayRU — accusative, as "по вторникам" and "в среду" both need it read
+// back. Index is time.Weekday.
+var weekdayRU = [...]string{"воскресеньям", "понедельникам", "вторникам", "средам", "четвергам", "пятницам", "субботам"}
+
+// activityRU glosses the loop's known fact keys. An unknown key is read back
+// verbatim: it is what the store holds, and inventing a Russian phrase for a key
+// maven does not recognise would be putting words in his mouth.
+var activityRU = map[string]string{
+	"water":   "пьёшь воду",
+	"meal":    "ешь",
+	"sleep":   "спишь",
+	"break":   "делаешь перерыв",
+	"shower":  "принимаешь душ",
+	"walk":    "гуляешь",
+	"pills":   "пьёшь витамины",
+	"workout": "тренируешься",
+}
+
+// FormatWeekdayRU reads back what he usually does on a given weekday.
+// Second person singular and informal, as she speaks TO him.
+func (p Profile) FormatWeekdayRU(wd time.Weekday) string {
+	acts := p.Weekly[wd]
+	day := weekdayRU[int(wd)%7]
+	if len(acts) == 0 {
+		return fmt.Sprintf("по %s у меня пока нет ничего постоянного.", day)
+	}
+	return fmt.Sprintf("по %s ты обычно %s.", day, joinActivities(acts))
+}
+
+// FormatOverallRU reads back the habits that hold across the whole week.
+func (p Profile) FormatOverallRU() string {
+	if len(p.All) == 0 {
+		return "я ещё не набрала достаточно записей, чтобы говорить о привычках."
+	}
+	return fmt.Sprintf("обычно ты %s.", joinActivities(p.All))
+}
+
+// maxRecited bounds a spoken profile. A list of fifteen habits read aloud is
+// not an answer; the most established few are.
+const maxRecited = 5
+
+func joinActivities(acts []Activity) string {
+	if len(acts) > maxRecited {
+		acts = acts[:maxRecited]
+	}
+	parts := make([]string, len(acts))
+	for i, a := range acts {
+		gloss, ok := activityRU[a.Key]
+		if !ok {
+			gloss = a.Key
+		}
+		parts[i] = fmt.Sprintf("%s около %02d:%02d", gloss,
+			int(a.TypicalAt.Hours()), int(a.TypicalAt.Minutes())%60)
+	}
+	if len(parts) == 1 {
+		return parts[0]
+	}
+	return strings.Join(parts[:len(parts)-1], ", ") + " и " + parts[len(parts)-1]
+}

internal/memory/behavior_test.go

@@ -0,0 +1,163 @@
+package memory
+
+import (
+	"strings"
+	"testing"
+	"time"
+	"unicode"
+)
+
+// habitHistory — n weeks of the same weekday, at the given local time.
+func habitHistory(key string, wd time.Weekday, hh, mm, weeks int, from time.Time) []Observation {
+	var out []Observation
+	d := from
+	for d.Weekday() != wd {
+		d = d.AddDate(0, 0, -1)
+	}
+	for i := 0; i < weeks; i++ {
+		day := d.AddDate(0, 0, -7*i)
+		out = append(out, Observation{
+			At:   time.Date(day.Year(), day.Month(), day.Day(), hh, mm, 0, 0, from.Location()),
+			Key:  key,
+			Kind: "self",
+		})
+	}
+	return out
+}
+
+func behaviorNow() time.Time {
+	// A Monday, so "по вторникам" is a past weekday and not today.
+	return time.Date(2026, 8, 3, 20, 0, 0, 0, time.UTC)
+}
+
+func TestBuildProfileCountsWeekdayHabits(t *testing.T) {
+	now := behaviorNow()
+	obs := append(
+		habitHistory("workout", time.Tuesday, 19, 0, 4, now),
+		habitHistory("water", time.Tuesday, 9, 0, 3, now)...,
+	)
+	p := BuildProfile(obs, now)
+
+	tue := p.Weekly[time.Tuesday]
+	if len(tue) != 2 {
+		t.Fatalf("got %d tuesday activities, want 2: %+v", len(tue), tue)
+	}
+	// Most-established first.
+	if tue[0].Key != "workout" || tue[0].Days != 4 {
+		t.Errorf("first = %+v, want workout on 4 days", tue[0])
+	}
+	if tue[0].TypicalAt != 19*time.Hour {
+		t.Errorf("typical at %v, want 19:00", tue[0].TypicalAt)
+	}
+	if len(p.Weekly[time.Wednesday]) != 0 {
+		t.Errorf("wednesday must be empty: %+v", p.Weekly[time.Wednesday])
+	}
+	if len(p.All) != 2 {
+		t.Errorf("the week-wide list should hold both: %+v", p.All)
+	}
+}
+
+// A one-off is not a habit. Saying "ты обычно X" off a single row is a
+// confidently wrong claim about his life.
+func TestBuildProfileNeedsMoreThanOneDay(t *testing.T) {
+	now := behaviorNow()
+	obs := habitHistory("workout", time.Tuesday, 19, 0, 1, now)
+	// Three rows, same day — a busy Tuesday, not a habit.
+	obs = append(obs, Observation{At: obs[0].At.Add(time.Hour), Key: "workout", Kind: "self"})
+	obs = append(obs, Observation{At: obs[0].At.Add(2 * time.Hour), Key: "workout", Kind: "self"})
+
+	p := BuildProfile(obs, now)
+	if len(p.All) != 0 || len(p.Weekly) != 0 {
+		t.Fatalf("one day of rows must produce no habit: %+v / %+v", p.All, p.Weekly)
+	}
+	if got := p.FormatOverallRU(); !strings.Contains(got, "не набрала достаточно") {
+		t.Errorf("empty profile reads %q", got)
+	}
+}
+
+// Only self-facts describe him. Env rows are the world and config rows are
+// maven's own tuning state; counting either as a habit would be a category
+// error the owner would then be told about.
+func TestBuildProfileIgnoresNonSelfAndMachineryKeys(t *testing.T) {
+	now := behaviorNow()
+	var obs []Observation
+	for _, o := range habitHistory("water", time.Tuesday, 9, 0, 3, now) {
+		o.Kind = "env"
+		obs = append(obs, o)
+	}
+	for _, o := range habitHistory("cooldown:water", time.Tuesday, 9, 0, 3, now) {
+		obs = append(obs, o) // kind=self, but a machinery key
+	}
+	for _, o := range habitHistory("calendar_event_20260804_standup", time.Tuesday, 10, 0, 3, now) {
+		obs = append(obs, o)
+	}
+	if p := BuildProfile(obs, now); len(p.All) != 0 {
+		t.Fatalf("nothing here is a habit of his: %+v", p.All)
+	}
+}
+
+// The median, not the mean: one 03:00 outlier must not move a morning habit
+// into the night.
+func TestBuildProfileTypicalTimeIsMedian(t *testing.T) {
+	now := behaviorNow()
+	obs := habitHistory("water", time.Tuesday, 9, 0, 4, now)
+	obs = append(obs, Observation{At: obs[0].At.AddDate(0, 0, -28).Add(-6 * time.Hour), Key: "water", Kind: "self"})
+	p := BuildProfile(obs, now)
+	if len(p.All) != 1 {
+		t.Fatalf("got %+v", p.All)
+	}
+	if p.All[0].TypicalAt != 9*time.Hour {
+		t.Errorf("typical at %v, want 09:00 despite the outlier", p.All[0].TypicalAt)
+	}
+}
+
+func TestProfileFormatRUPersona(t *testing.T) {
+	now := behaviorNow()
+	obs := append(
+		habitHistory("workout", time.Tuesday, 19, 0, 4, now),
+		habitHistory("water", time.Tuesday, 9, 5, 3, now)...,
+	)
+	p := BuildProfile(obs, now)
+
+	got := p.FormatWeekdayRU(time.Tuesday)
+	want := "по вторникам ты обычно тренируешься около 19:00 и пьёшь воду около 09:05."
+	if got != want {
+		t.Errorf("got  %q\nwant %q", got, want)
+	}
+	if empty := p.FormatWeekdayRU(time.Thursday); !strings.Contains(empty, "ничего постоянного") {
+		t.Errorf("an unknown weekday reads %q", empty)
+	}
+	// Persona: she addresses him informally, never in the masculine about
+	// herself, and never with a pet name.
+	for _, s := range []string{got, p.FormatOverallRU(), p.FormatWeekdayRU(time.Thursday)} {
+		// Whole words: "ничего" contains "его", and a substring test would
+		// call a correct sentence a persona violation.
+		for _, tok := range strings.FieldsFunc(strings.ToLower(s), func(r rune) bool {
+			return !unicode.IsLetter(r)
+		}) {
+			switch tok {
+			case "рад", "понял", "вы", "ваш", "ваши", "милый", "дорогой", "он", "его":
+				t.Errorf("%q uses %q", s, tok)
+			}
+		}
+	}
+}
+
+// An unrecognised key is read back verbatim rather than glossed into something
+// maven made up.
+func TestProfileUnknownKeyReadBackVerbatim(t *testing.T) {
+	now := behaviorNow()
+	p := BuildProfile(habitHistory("починил кран", time.Tuesday, 12, 0, 2, now), now)
+	if got := p.FormatOverallRU(); !strings.Contains(got, "починил кран") {
+		t.Errorf("got %q", got)
+	}
+}
+
+// A future-dated row is a clock problem, not a habit.
+func TestBuildProfileIgnoresFutureRows(t *testing.T) {
+	now := behaviorNow()
+	obs := habitHistory("water", time.Tuesday, 9, 0, 3, now.AddDate(0, 2, 0))
+	if p := BuildProfile(obs, now); len(p.All) != 0 {
+		t.Fatalf("future rows counted: %+v", p.All)
+	}
+}

internal/router/habit.go

@@ -0,0 +1,73 @@
+package router
+
+import "time"
+
+// Habit queries — "что я обычно делаю по вторникам?" (Vikunja #254).
+//
+// Deterministic matching, like the calendar and plan matchers: the LLM router
+// classifies the intent, but WHICH weekday was asked about is a lookup, not a
+// generation. A model that answers "по вторникам" for a question about Thursday
+// gives a confidently wrong account of the owner's own life.
+
+// HabitQuery — a parsed "what do I usually do" question. Weekday is set only
+// when the utterance names one; otherwise the answer covers the whole week.
+type HabitQuery struct {
+	Weekday    time.Weekday
+	HasWeekday bool
+}
+
+// habitMarkers — the words that make a question about habit rather than about
+// today. Without one of these, "что я делаю" is a question about right now, and
+// the recall path owns it.
+var habitMarkers = []string{
+	"обычно", "обычное", "чаще", "постоянно", "привычки", "привычка", "привычках",
+	"регулярно", "каждый", "каждую", "каждое", "usually", "habits", "habit",
+	"typically", "normally",
+}
+
+// weekdayWords — every form of a weekday name maven needs to recognise,
+// including the "по …ам" plural the question is usually phrased in.
+var weekdayWords = map[string]time.Weekday{
+	"понедельник": time.Monday, "понедельникам": time.Monday,
+	"вторник": time.Tuesday, "вторникам": time.Tuesday,
+	"среда": time.Wednesday, "среду": time.Wednesday, "средам": time.Wednesday,
+	"четверг": time.Thursday, "четвергам": time.Thursday,
+	"пятница": time.Friday, "пятницу": time.Friday, "пятницам": time.Friday,
+	"суббота": time.Saturday, "субботу": time.Saturday, "субботам": time.Saturday,
+	"воскресенье": time.Sunday, "воскресеньям": time.Sunday,
+	"monday": time.Monday, "mondays": time.Monday,
+	"tuesday": time.Tuesday, "tuesdays": time.Tuesday,
+	"wednesday": time.Wednesday, "wednesdays": time.Wednesday,
+	"thursday": time.Thursday, "thursdays": time.Thursday,
+	"friday": time.Friday, "fridays": time.Friday,
+	"saturday": time.Saturday, "saturdays": time.Saturday,
+	"sunday": time.Sunday, "sundays": time.Sunday,
+}
+
+// ParseHabitQuery reports whether an utterance asks what the owner usually
+// does, and on which weekday if it names one.
+//
+// A habit marker is required. "что я делаю в среду?" without one is a question
+// about this coming Wednesday — the calendar's job — and answering it with a
+// statistical average would be answering a different question.
+func ParseHabitQuery(text string) (HabitQuery, bool) {
+	toks := planTokens(text)
+	marked := false
+	for _, t := range toks {
+		for _, m := range habitMarkers {
+			if t == m {
+				marked = true
+				break
+			}
+		}
+	}
+	if !marked {
+		return HabitQuery{}, false
+	}
+	for _, t := range toks {
+		if wd, ok := weekdayWords[t]; ok {
+			return HabitQuery{Weekday: wd, HasWeekday: true}, true
+		}
+	}
+	return HabitQuery{}, true
+}

internal/router/habit_test.go

@@ -0,0 +1,45 @@
+package router
+
+import (
+	"testing"
+	"time"
+)
+
+func TestParseHabitQuery(t *testing.T) {
+	tests := []struct {
+		in    string
+		ok    bool
+		wd    time.Weekday
+		hasWD bool
+	}{
+		{"что я обычно делаю по вторникам?", true, time.Tuesday, true},
+		{"что я обычно делаю?", true, 0, false},
+		{"какие у меня привычки", true, 0, false},
+		{"что я каждую пятницу делаю", true, time.Friday, true},
+		{"what do i usually do on mondays?", true, time.Monday, true},
+		// No habit marker: this is a question about the coming Wednesday, and
+		// the calendar owns it. Answering with an average answers the wrong
+		// question.
+		{"что я делаю в среду?", false, 0, false},
+		{"что у меня сегодня?", false, 0, false},
+		{"какие планы на сегодня?", false, 0, false},
+		{"", false, 0, false},
+	}
+	for _, tt := range tests {
+		q, ok := ParseHabitQuery(tt.in)
+		if ok != tt.ok {
+			t.Errorf("ParseHabitQuery(%q) ok = %v, want %v", tt.in, ok, tt.ok)
+			continue
+		}
+		if !ok {
+			continue
+		}
+		if q.HasWeekday != tt.hasWD {
+			t.Errorf("ParseHabitQuery(%q) hasWeekday = %v, want %v", tt.in, q.HasWeekday, tt.hasWD)
+			continue
+		}
+		if q.HasWeekday && q.Weekday != tt.wd {
+			t.Errorf("ParseHabitQuery(%q) weekday = %v, want %v", tt.in, q.Weekday, tt.wd)
+		}
+	}
+}