issue-tracker.changes reads each issue's moves over a window from the tracker's own log, so progress since says from what each issue moved, not only where it is

modules/mesh-issues/cmd/mesh-issues/main.go

@@ -23,7 +23,7 @@ const Seat = "issue-tracker"
 
 // Verbs are the seat's verbs, as the manifest declares and claims them.
 var Verbs = []string{"open", "get", "list", "move", "note", "link", "milestones", "milestone-set", "milestone-move", "import",
-	"groom", "set", "tracking", "reserve", "fix-times", "learn-fixes"}
+	"groom", "set", "tracking", "reserve", "fix-times", "learn-fixes", "changes"}
 
 func logf(format string, a ...any) { fmt.Fprintf(os.Stderr, format+"\n", a...) }
 
@@ -943,5 +943,6 @@ func Tools(t *Tracker) []stdio.Tool {
 				}
 				return t.LearnFixes(n)
 			}},
+		changesTool(t),
 	}
 }

modules/mesh-issues/cmd/mesh-issues/milestone_bus_test.go

@@ -72,6 +72,13 @@ func TestAnIssueRaceIntoTwoMilestonesOverTheBusEndsInOne(t *testing.T) {
 	if len(hist.History) != 1 {
 		t.Fatalf("history %d values", len(hist.History))
 	}
+	// The moves history over the real log: the open, from nothing to open, read by the other instance.
+	var ch ChangesRead
+	_ = json.Unmarshal(must(two.call("changes", map[string]any{"since": "60m"})), &ch)
+	if len(ch.Changes) != 1 || ch.Changes[0].Number != 365 || ch.Changes[0].Kind != OpOpened || ch.Changes[0].To != StatusOpen ||
+		ch.Changes[0].Title != "a milestone's issue" {
+		t.Fatalf("changes %+v", ch)
+	}
 	evMu.Lock()
 	defer evMu.Unlock()
 	var kinds []string

modules/mesh-issues/cmd/mesh-issues/moves.go

@@ -0,0 +1,222 @@
+package main
+
+// changes: each issue's moves over a window, read from the tracker's own record, its log `changes` (novox/hq ADR 0300),
+// which holds every operation with who made it and when. The bucket `issues` keeps only what they add up to, so this
+// is the one place an issue's earlier status is known: knowledge-base.progress with since asks it for the "from" of
+// each move (the operator, 2026-10-28: the progress made in the last 60 minutes).
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	stdio "git.novox.be/novox/mesh-sdk/go"
+)
+
+// MostChangesWindow is the longest window changes reads.
+const MostChangesWindow = 24 * time.Hour
+
+// MostChanges is the most changes one answer holds, the newest kept.
+const MostChanges = 500
+
+// changesSlack is how far before the window the log is read from: an entry's time is the bus's, an operation's the
+// tracker's, and the two may differ by a little.
+const changesSlack = time.Minute
+
+// Change is one issue's status changing: opened, moved, resolved or wontfix, from what to what, by whom and when.
+type Change struct {
+	Number uint64 `json:"number"`
+	Title  string `json:"title,omitempty"`
+	Kind   string `json:"kind"`
+	From   string `json:"from"`
+	To     string `json:"to"`
+	By     string `json:"by"`
+	// Worker is who works on it, for a move to diagnosing or fixing: whom by names (the caller is By).
+	Worker string    `json:"worker,omitempty"`
+	At     time.Time `json:"at"`
+}
+
+// ChangesRead is the answer of changes.
+type ChangesRead struct {
+	Since   time.Time `json:"since"`
+	Changes []Change  `json:"changes"`
+	// Entries is how many entries of the log were read for it.
+	Entries int    `json:"entries-read"`
+	Said    string `json:"said"`
+}
+
+// Changes reads the moves of the last window, of every issue or of one.
+func (t *Tracker) Changes(window time.Duration, number uint64) (*ChangesRead, error) {
+	if window <= 0 || window > MostChangesWindow {
+		return nil, fmt.Errorf("since is a window more than nothing and at most 24h, not %s", window)
+	}
+	if t.Log == nil {
+		return nil, errNoLog
+	}
+	from := t.now().Add(-window)
+	out := &ChangesRead{Since: from, Changes: []Change{}}
+	var numbers []uint64
+	if number != 0 {
+		numbers = []uint64{number}
+	} else {
+		var err error
+		if numbers, err = t.movedSince(from, out); err != nil {
+			return nil, err
+		}
+	}
+	for _, n := range numbers {
+		entries, err := t.readKey(n, 1)
+		if err != nil {
+			return nil, err
+		}
+		if len(entries) == 0 {
+			if number != 0 {
+				return nil, fmt.Errorf("%d is not an issue the tracker holds", n)
+			}
+			continue
+		}
+		out.Entries += len(entries)
+		var cur *Issue
+		for _, e := range entries {
+			var op Operation
+			if err := json.Unmarshal(e.Value, &op); err != nil {
+				return nil, fmt.Errorf("the entry at %d is no operation this module reads: %v", e.Sequence, err)
+			}
+			next, err := fold(cur, &op, e.Sequence)
+			if err != nil {
+				return nil, fmt.Errorf("issue %d cannot be folded from its log: %v", n, err)
+			}
+			was := ""
+			if cur != nil {
+				was = cur.Status
+			}
+			cur = next
+			if op.Op == OpCarried || op.At.Before(from) || (was == next.Status && was != "") {
+				continue
+			}
+			kind := EventMoved
+			switch {
+			case was == "" && (op.Op == OpOpened || op.Op == OpImported):
+				kind = op.Op
+			case next.Status == StatusResolved || next.Status == StatusWontfix:
+				kind = next.Status
+			}
+			c := Change{Number: n, Kind: kind, From: was, To: next.Status, By: op.By, At: op.At}
+			if next.Worker != nil && (next.Status == StatusDiagnosing || next.Status == StatusFixing) {
+				c.Worker = next.Worker.By
+			}
+			out.Changes = append(out.Changes, c)
+		}
+		for i := range out.Changes {
+			if out.Changes[i].Number == n && cur != nil {
+				out.Changes[i].Title = cur.Title
+			}
+		}
+	}
+	sort.SliceStable(out.Changes, func(i, j int) bool {
+		if !out.Changes[i].At.Equal(out.Changes[j].At) {
+			return out.Changes[i].At.Before(out.Changes[j].At)
+		}
+		return out.Changes[i].Number < out.Changes[j].Number
+	})
+	cut := ""
+	if len(out.Changes) > MostChanges {
+		cut = fmt.Sprintf("; the oldest %d are left out", len(out.Changes)-MostChanges)
+		out.Changes = out.Changes[len(out.Changes)-MostChanges:]
+	}
+	out.Said = fmt.Sprintf("%d changes of status since %s, from the tracker's log (%d entries read)%s.",
+		len(out.Changes), from.Format(time.RFC3339), out.Entries, cut)
+	return out, nil
+}
+
+// movedSince is every issue an operation of which was written from the window on, found in the whole log by its
+// entries' times: the first entry of the window is searched for, then the log is read on from it.
+func (t *Tracker) movedSince(from time.Time, out *ChangesRead) ([]uint64, error) {
+	first, err := t.Log.Read(1, "", 1)
+	if err != nil {
+		return nil, fmt.Errorf("the log could not be read: %v", err)
+	}
+	if len(first.Entries) == 0 {
+		return nil, nil
+	}
+	lo, hi := first.Entries[0].Sequence, first.Last
+	start := from.Add(-changesSlack)
+	// The first sequence whose entry is at or after start: the entries are in the order they were written.
+	for lo < hi {
+		mid := lo + (hi-lo)/2
+		p, err := t.Log.Read(mid, "", 1)
+		if err != nil {
+			return nil, fmt.Errorf("the log could not be read at %d: %v", mid, err)
+		}
+		out.Entries++
+		if len(p.Entries) == 0 || !p.Entries[0].At.Before(start) {
+			hi = mid
+		} else {
+			lo = p.Entries[0].Sequence + 1
+		}
+	}
+	seen := map[uint64]bool{}
+	var numbers []uint64
+	for seq := lo; seq != 0; {
+		p, err := t.Log.Read(seq, "", logPage)
+		if err != nil {
+			return nil, fmt.Errorf("the log could not be read from %d: %v", seq, err)
+		}
+		out.Entries += len(p.Entries)
+		for _, e := range p.Entries {
+			n, ok := numberOfKey(e.Key)
+			if !ok || seen[n] || e.At.Before(start) || !movesStatus(e) {
+				continue
+			}
+			seen[n] = true
+			numbers = append(numbers, n)
+		}
+		seq = p.Next
+	}
+	return numbers, nil
+}
+
+// movesStatus says whether a log entry may change an issue's status: one that holds the issue whole, or sets it.
+func movesStatus(e stdio.LogEntry) bool {
+	var op Operation
+	if json.Unmarshal(e.Value, &op) != nil {
+		return true
+	}
+	_, sets := op.Set["status"]
+	return sets || (op.Issue != nil && op.Op != OpCarried)
+}
+
+// changesTool is the verb, its arguments read as the other verbs read them.
+func changesTool(t *Tracker) stdio.Tool {
+	return stdio.Tool{Name: Seat + ".changes",
+		Description: "Each issue's moves over a window, from the tracker's own log of every change: the issue moves history " +
+			"of the last minutes or hours (since, such as 60m, at most 24h), every issue's or one's (number), each change " +
+			"opened, moved, resolved or wontfix with the status it moved from and to, who moved it and when, oldest first. " +
+			"What the issues are now is list and get; this is what they were before. Refused: a window of nothing or over " +
+			"24h, a number that is not an issue.",
+		Input: schema([]string{"since"}, map[string]any{
+			"since":  text("the window, back from now: 60m, 5m, 2h, at most 24h"),
+			"number": number("only this issue"),
+		}),
+		Run: func(m map[string]any) (any, error) {
+			a, err := readArgs("changes", m, "since", "number")
+			if err != nil {
+				return nil, err
+			}
+			s, err := a.str("since")
+			if err != nil {
+				return nil, err
+			}
+			d, err := time.ParseDuration(strings.TrimSpace(s))
+			if err != nil {
+				return nil, fmt.Errorf("since is a window such as 60m, 5m or 2h, not %q", s)
+			}
+			n, err := a.number("number", false)
+			if err != nil {
+				return nil, err
+			}
+			return t.Changes(d, n)
+		}}
+}

modules/mesh-issues/cmd/mesh-issues/moves_test.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+	"time"
+)
+
+// changes reads the tracker's own log over a window (the lead, 2026-10-28, for knowledge-base.progress since): each
+// move from what to what, by whom and when, and each open, as the tracker's verbs wrote them into its log here.
+func TestChangesSaysEachMoveFromWhatToWhatOverAWindow(t *testing.T) {
+	h := newHarness(t)
+	clock := time.Date(2026, 10, 28, 9, 0, 0, 0, time.UTC)
+	h.Tracker.Now = func() time.Time { return clock }
+	at := func(hh, mm int) { clock = time.Date(2026, 10, 28, hh, mm, 0, 0, time.UTC); h.log.clock = clock }
+	at(9, 0)
+	a := h.open(t, "an issue fixed in the window", "hq")
+	at(9, 10)
+	b := h.open(t, "an issue given up in the window")
+	at(10, 0)
+	if _, err := h.Move(MoveAsk{Number: a, Status: StatusDiagnosing, By: "a@g14"}); err != nil {
+		t.Fatal(err)
+	}
+	at(10, 30)
+	if _, err := h.Move(MoveAsk{Number: a, Status: StatusFixing, By: "a@g14"}); err != nil {
+		t.Fatal(err)
+	}
+	at(10, 40)
+	if _, err := h.Note(a, "a note moves nothing"); err != nil {
+		t.Fatal(err)
+	}
+	at(11, 0)
+	if _, err := h.Move(MoveAsk{Number: a, Status: StatusResolved, FixedBy: []string{"hq#1"}}); err != nil {
+		t.Fatal(err)
+	}
+	at(11, 5)
+	if _, err := h.Move(MoveAsk{Number: b, Status: StatusWontfix, Reason: "the module is retired"}); err != nil {
+		t.Fatal(err)
+	}
+	at(11, 30)
+	say := func(r *ChangesRead) string {
+		var lines []string
+		for _, c := range r.Changes {
+			lines = append(lines, strings.Join([]string{c.At.Format("15:04"), c.Kind, itoa(int(c.Number)), c.From + ">" + c.To, c.By + "/" + c.Worker}, " "))
+		}
+		return strings.Join(lines, "\n")
+	}
+	got, err := h.call(t, "changes", map[string]any{"since": "60m"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	r := got.(*ChangesRead)
+	if want := "10:30 moved 365 diagnosing>fixing " + Unproven + "/a@g14\n11:00 resolved 365 fixing>resolved " + Unproven + "/\n11:05 wontfix 366 open>wontfix " + Unproven + "/"; say(r) != want {
+		t.Errorf("the last hour:\n%s\nwant\n%s", say(r), want)
+	}
+	if !r.Since.Equal(time.Date(2026, 10, 28, 10, 30, 0, 0, time.UTC)) || r.Changes[0].Title != "an issue fixed in the window" || !strings.Contains(r.Said, "3 changes") {
+		t.Errorf("since %v, title %q, said %q", r.Since, r.Changes[0].Title, r.Said)
+	}
+	got, err = h.call(t, "changes", map[string]any{"since": "3h", "number": b})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want := "09:10 opened 366 >open " + Unproven + "/\n11:05 wontfix 366 open>wontfix " + Unproven + "/"; say(got.(*ChangesRead)) != want {
+		t.Errorf("one issue:\n%s", say(got.(*ChangesRead)))
+	}
+	raw, _ := json.Marshal(got)
+	if !strings.Contains(string(raw), `"from":"open","to":"wontfix"`) {
+		t.Errorf("as JSON: %s", raw)
+	}
+	for _, bad := range []map[string]any{{"since": "25h"}, {"since": "0m"}, {}, {"since": "60m", "number": 9999}} {
+		if _, err := h.call(t, "changes", bad); err == nil {
+			t.Errorf("%v was answered", bad)
+		}
+	}
+}