A tool reads one module's bindings again from the seat events the shared stream still holds (issue 1966)

A binding the bus module said created that the part did not keep had no
recovery: distribution's holds, windows, mirrors and events are missing on
the bus node's memberships. grants_bindings_again, a hand act, asks the
process to read the seat mesh-broker's created, recreated and dropped of
one module again from EVENTS by sequence and keep each through HearBroker
in order, so a dropped entry stays dropped. grants_bindings shows what it
kept, and says when the stream no longer holds a created: then the seat's
list answering bindings is the path (the record extending ADR 0595 §7).
The part alone is granted the stream's message get, no consumer.

Claude-Session: https://claude.ai/code/session_01NcbgfFSnn24M3GcqttoU7i

modules/mesh-grants/cmd/mesh-grants/history.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"git.novox.be/novox/mesh-contracts/go/seats/meshbroker"
+	"github.com/nats-io/nats.go"
+
+	"mesh-grants/internal/buscompose"
+	"mesh-grants/internal/grants"
+)
+
+// readAgainAtMost bounds one re-read of the seat mesh-broker's events (grants_bindings_again): a stream holding more of
+// them than this is read up to here, and the answer says the rest was not read.
+const readAgainAtMost = 20000
+
+// brokerHistory reads the seat mesh-broker's events again from the shared events stream, by sequence and subject
+// (STREAM.MSG.GET with next_by_subj, the grant buscompose.SeatEventsReadAgain): a get per event, no consumer, oldest first.
+type brokerHistory struct {
+	ctx context.Context
+	nc  *nats.Conn
+}
+
+// msgGetAnswer is the bus's answer to a STREAM.MSG.GET.
+type msgGetAnswer struct {
+	Message *struct {
+		Subject string    `json:"subject"`
+		Seq     uint64    `json:"seq"`
+		Data    []byte    `json:"data"`
+		Time    time.Time `json:"time"`
+	} `json:"message"`
+	Error *struct {
+		Code        int    `json:"code"`
+		ErrCode     int    `json:"err_code"`
+		Description string `json:"description"`
+	} `json:"error"`
+}
+
+// noMessage is the bus's error code for a get past the last message of the subject.
+const noMessage = 10037
+
+func (h brokerHistory) Said() ([]grants.SaidEvent, error) {
+	subject := "mesh.seat." + meshbroker.Seat + ".event.*"
+	var out []grants.SaidEvent
+	for seq := uint64(1); ; {
+		if len(out) >= readAgainAtMost {
+			return out, fmt.Errorf("the stream holds more than %d of the seat's events: read up to sequence %d, the rest not", readAgainAtMost, seq)
+		}
+		body, _ := json.Marshal(map[string]any{"seq": seq, "next_by_subj": subject})
+		ctx, cancel := context.WithTimeout(h.ctx, requestWithin)
+		reply, err := h.nc.RequestWithContext(ctx, buscompose.SeatEventsReadAgain, body)
+		cancel()
+		if err != nil {
+			return out, fmt.Errorf("%s at sequence %d: %w", buscompose.SeatEventsReadAgain, seq, err)
+		}
+		var a msgGetAnswer
+		if err := json.Unmarshal(reply.Data, &a); err != nil {
+			return out, fmt.Errorf("%s answered what does not read: %w", buscompose.SeatEventsReadAgain, err)
+		}
+		if a.Error != nil {
+			if a.Error.ErrCode == noMessage {
+				return out, nil
+			}
+			return out, fmt.Errorf("%s at sequence %d: %s", buscompose.SeatEventsReadAgain, seq, a.Error.Description)
+		}
+		if a.Message == nil {
+			return out, nil
+		}
+		out = append(out, grants.SaidEvent{Subject: a.Message.Subject, Data: a.Message.Data, At: a.Message.Time})
+		seq = a.Message.Seq + 1
+	}
+}

modules/mesh-grants/cmd/mesh-grants/integration_test.go

@@ -316,6 +316,24 @@ func TestTheGrantsPartWhole(t *testing.T) {
 	})
 	sayBroker("dropped", membership.BusBinding{Local: "kept"})
 	until("mod-c's binding gone after dropped", func() bool { return len(bindingOf()) == 0 })
+	// Issue 1966, grants_bindings_again: asked as the tool asks, the process reads the seat's events again from EVENTS by
+	// sequence (brokerHistory) and keeps mod-c's created and dropped in their order, so the dropped entry stays dropped.
+	ask, _ := json.Marshal(grants.Ask{By: "jochen@shanks", At: time.Now(), Bindings: "mod-c"})
+	if _, err := kvs[grants.Module+"."+grants.StateUserList].Put(ctx, grants.KeyAsked, ask); err != nil {
+		t.Fatal(err)
+	}
+	until("mod-c's bindings read again from EVENTS", func() bool {
+		e, err := kvs[grants.Module+"."+grants.StateUserList].Get(ctx, grants.KeyBindingsAgain)
+		if err != nil {
+			return false
+		}
+		var again grants.BindingsAgain
+		return json.Unmarshal(e.Value(), &again) == nil && again.Module == "mod-c" && again.Read == 2 && again.Error == "" &&
+			slices.Equal(again.Dropped, []string{"kept"}) && len(again.Kept) == 0
+	})
+	if b := bindingOf(); len(b) != 0 {
+		t.Errorf("a dropped binding came back from the re-read: %+v", b)
+	}
 	for _, bucket := range []string{"mesh-controller_lease", grants.Module + "_lease", grants.Module + "_takeover"} {
 		if _, err := js.KeyValue(ctx, bucket); !errors.Is(err, jetstream.ErrBucketNotFound) {
 			t.Errorf("the bucket %s: %v, want none", bucket, err)

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

@@ -135,6 +135,7 @@ func run(ctx context.Context, getenv func(string) string, logOut io.Writer) erro
 		Objects: sealedObjects{ctx: ctx, js: js}, Purging: ownPurging{ctx: ctx, js: js, module: account.Module}, Logf: logger.Printf,
 		Bus: grants.BusAddress{URL: account.URL, Fingerprint: account.Fingerprint}}
 	f.Watch = fv
+	f.Part.History = brokerHistory{ctx: ctx, nc: nc}
 	// The seat list: read over the connection and the hub, given to catalogue at every change, and a pass composes again then.
 	gate := &seatGate{}
 	gate.follow(seatlist.ProcessBus(conn.Call, hub), f.Wake, logger.Printf)

modules/mesh-grants/cmd/mesh-grants/tools.go

@@ -256,13 +256,26 @@ func toolsOf(p *grants.Part) []stdio.Tool {
 			"every membership of the module the part wrote, and the kept bindings a membership lacks. One module, or every one. Read-only.",
 			Input: schema(map[string]string{"module": "one module, e.g. distribution; none for every one"}),
 			Run:   func(a map[string]any) (any, error) { return p.BindingsOf(grants.Answer(a, "module")) }},
+		{Name: grants.ToolBindingsAgain, Description: "Read one module's bindings again from the seat mesh-broker's created, " +
+			"recreated and dropped that the shared events stream still holds, kept as if heard now (issue 1966), by a person's act " +
+			"with why, recorded as a hand act: the step when grants_bindings lacks an entry the bus module made. Asks the part's " +
+			"process; grants_bindings shows what it kept, what was already kept, and when the stream no longer holds the created.",
+			Input: schema(map[string]string{"module": "the module, e.g. distribution", "why": "why, kept in the hand act"}, "module", "why"),
+			Run: func(a map[string]any) (any, error) {
+				return p.AskBindingsAgain(stdio.CallerOf(a), grants.Answer(a, "module"), grants.Answer(a, "why"), recordHandActFor("bindings-again"))
+			}},
 	}
 }
 
-// recordHandAct records a person's act through the seat mesh-hand-acts.
-func recordHandAct(what, why string) error {
-	_, err := meshhandactsclient.Recorder{Ask: stdio.Ask}.Record(meshhandactsclient.Request{What: what, Why: why, Cause: "first-view-again"})
-	return err
+// recordHandAct records a person's act of grants_first_view_again through the seat mesh-hand-acts.
+func recordHandAct(what, why string) error { return recordHandActFor("first-view-again")(what, why) }
+
+// recordHandActFor records a person's act through the seat mesh-hand-acts, with its cause.
+func recordHandActFor(cause string) func(what, why string) error {
+	return func(what, why string) error {
+		_, err := meshhandactsclient.Recorder{Ask: stdio.Ask}.Record(meshhandactsclient.Request{What: what, Why: why, Cause: cause})
+		return err
+	}
 }
 
 // serveTools serves the tools to the runtime until it stops.

modules/mesh-grants/grants_test.go

@@ -3189,6 +3189,56 @@ func TestGrants(t *testing.T) {
 		if got := bindingsOn("a.mod-x"); len(got) != 0 {
 			t.Errorf("after dropped: %+v", got)
 		}
+		// Issue 1966, grants_bindings_again (the lead's ruling, option b): the process reads the seat's events the shared
+		// stream still holds again, oldest first, and keeps one module's created, recreated and dropped as if heard now: a
+		// binding never kept comes back, one dropped since stays dropped, another module's is left; the hand act is recorded
+		// before the ask, and an ask without why or a module is refused.
+		event := func(name, module, local, bucket string) grants.SaidEvent {
+			body, _ := json.Marshal(grants.BrokerEvent{V: 1, Module: module, LocalName: local, StorageType: "key-value", Template: "state",
+				Binding: membership.BusBinding{Local: local, Storage: "key-value", Template: "state", Bucket: bucket}})
+			return grants.SaidEvent{Subject: "mesh.seat.mesh-broker.event." + name, Data: body, At: time.Date(2026, 11, 3, 0, 0, 0, 0, time.UTC)}
+		}
+		p.Create = b
+		p.History = saidHistory{event("created", "mod-x", "windows", "mod-x_windows"), event("refused", "mod-x", "mirrors", ""),
+			event("created", "mod-y", "other", "mod-y_other"), event("created", "mod-x", "gone", "mod-x_gone"),
+			event("dropped", "mod-x", "gone", "")}
+		var acts []string
+		record := func(what, why string) error { acts = append(acts, what+": "+why); return nil }
+		for _, bad := range [][2]string{{"mod-x", ""}, {"", "x"}, {"a.mod-x", "x"}} {
+			if _, err := p.AskBindingsAgain("jochen@shanks", bad[0], bad[1], record); err == nil || len(acts) != 0 {
+				t.Errorf("grants_bindings_again %q %q was asked: %v %v", bad[0], bad[1], err, acts)
+			}
+		}
+		readAgain := func(module string) string {
+			if _, err := p.AskBindingsAgain("jochen@shanks", module, "distribution's lost bindings", record); err != nil {
+				t.Fatalf("grants_bindings_again %s: %v", module, err)
+			}
+			p.Compose()
+			got, err := p.BindingsOf(module)
+			if err != nil {
+				t.Fatal(err)
+			}
+			raw, _ := json.Marshal(got)
+			return string(raw)
+		}
+		if got := readAgain("mod-x"); !strings.Contains(got, `"kept":["windows"],"already":[],"dropped":["gone"]`) || !strings.Contains(got, `"read":3`) {
+			t.Errorf("the first re-read: %s", got)
+		}
+		if got := bindingsOn("a.mod-x"); len(got) != 1 || got[0].Bucket != "mod-x_windows" {
+			t.Errorf("after the re-read, mod-x's membership carries %+v", got)
+		}
+		if raw, _, found, _ := b.ownGet(grants.StateMemberships, grants.BoundKey("mod-y")); found {
+			t.Errorf("another module's binding was kept by mod-x's re-read: %s", raw)
+		}
+		if got := readAgain("mod-x"); !strings.Contains(got, `"kept":[],"already":["windows"]`) {
+			t.Errorf("the second re-read: %s", got)
+		}
+		if got := readAgain("mod-z"); !strings.Contains(got, "holds no created or recreated of mod-z") || !strings.Contains(got, "seat mesh-broker's list") {
+			t.Errorf("a module whose created the stream no longer holds: %s", got)
+		}
+		if len(acts) != 3 || !strings.HasPrefix(acts[0], "grants_bindings_again mod-x: ") {
+			t.Errorf("hand acts %v", acts)
+		}
 	})
 
 	// Issue 1966 (F2), the conformance row: an entry asked in `requires` is granted where its old section is. For a
@@ -4625,3 +4675,8 @@ func oldStateReaders(path string, src []byte) ([]string, error) {
 	}
 	return out, nil
 }
+
+// saidHistory is the seat mesh-broker's events a shared events stream holds, oldest first (grants.BrokerHistory).
+type saidHistory []grants.SaidEvent
+
+func (h saidHistory) Said() ([]grants.SaidEvent, error) { return h, nil }

modules/mesh-grants/internal/buscompose/buscompose_test.go

@@ -600,13 +600,18 @@ func TestTheCopiedComposerComposesAsTheControllers(t *testing.T) {
 			t.Errorf("a one-filter consumer's grants = %v: its update is the no-filter create form", one)
 		}
 		for _, u := range users {
-			if u.Module != GrantsModule || u.Kind != KindModule {
-				continue
-			}
 			perms, err := PermissionsFor(u)
 			if err != nil {
 				t.Fatal(err)
 			}
+			// Issue 1966: the grants part alone reads the shared events stream by sequence, to read the seat mesh-broker's
+			// events again (grants_bindings_again).
+			if may := MayPublish(perms, "$JS.API.STREAM.MSG.GET.EVENTS"); may != (u.Module == GrantsModule && u.Kind == KindModule) {
+				t.Errorf("%s %s may read EVENTS by sequence: %v", u.Kind, u.Module, may)
+			}
+			if u.Module != GrantsModule || u.Kind != KindModule {
+				continue
+			}
 			if !MayPublish(perms, "$JS.API.CONSUMER.CREATE.EVENTS.a_m") || MayPublish(perms, "$JS.API.CONSUMER.CREATE.EVENTS.a_quiet") ||
 				MayPublish(perms, "$JS.API.CONSUMER.DELETE.EVENTS.a_m") || MayPublish(perms, "$JS.API.CONSUMER.CREATE.EVENTS.a_m.mesh.mod.x.event.happened") {
 				t.Errorf("the grants part creates consumers as %v", u.CreatesConsumers)

modules/mesh-grants/internal/buscompose/nats.go

@@ -859,6 +859,10 @@ func PermissionsFor(p Principal) (Permissions, error) {
 			pub = append(pub, CreateConsumerGrants(p.CreatesConsumers)...)
 			// And its own object bucket, where it writes the user list sealed to the bus node (ADR 0547 clause 7).
 			pub = append(pub, GrantsUserListWrites()...)
+			// And the read of one message of the shared events stream by its sequence and subject, where the part reads the
+			// seat mesh-broker's created, recreated and dropped again for grants_bindings_again (issue 1966): a get, never a
+			// consumer, so no other account's consumer is touched.
+			pub = append(pub, SeatEventsReadAgain)
 		}
 		// The view alone reads the build seats' workers for the backlog of asks (issue 1887 A8a).
 		if p.Module == ViewModule {
@@ -1546,6 +1550,10 @@ func CreateConsumerGrants(consumers []ModuleConsumer) []string {
 	return out
 }
 
+// SeatEventsReadAgain is the grants part's read of the shared events stream by sequence (STREAM.MSG.GET with
+// next_by_subj): a binding the bus module said that the part did not keep is read again from it (issue 1966).
+const SeatEventsReadAgain = "$JS.API.STREAM.MSG.GET." + EventsStream
+
 // GrantsModule is the one module whose principal publishes the modules' memberships (novox/hq ADR 0547 §5): the grants
 // part, which composes them from the manifests and assignments. It defines no stream and is granted no other subject here.
 const GrantsModule = "mesh-grants"

modules/mesh-grants/internal/grants/bindings.go

@@ -10,6 +10,7 @@ import (
 	"slices"
 	"sort"
 	"strings"
+	"time"
 
 	"git.novox.be/novox/mesh-sdk/go/membership"
 	"mesh-grants/internal/buscompose"
@@ -245,11 +246,174 @@ func (p *Part) BindingsOf(module string) (any, error) {
 		}
 		out = append(out, k)
 	}
-	if module != "" && len(out) == 0 {
-		return map[string]any{"modules": out, "says": "the part keeps no binding of " + module + ": the bus module said no created for it that the part heard"}, nil
+	again, err := p.lastBindingsAgain(module)
+	if err != nil {
+		return nil, err
 	}
-	return map[string]any{"modules": out,
-		"says": "each binding the part kept from the bus module's created and recreated, beside the memberships it wrote; lacking names a kept binding a membership does not carry yet"}, nil
+	answer := map[string]any{"modules": out,
+		"says": "each binding the part kept from the bus module's created and recreated, beside the memberships it wrote; lacking names a kept binding a membership does not carry yet"}
+	if module != "" && len(out) == 0 {
+		answer["says"] = "the part keeps no binding of " + module + ": the bus module said no created for it that the part heard"
+	}
+	if again != nil {
+		answer["read-again"] = again
+	}
+	return answer, nil
+}
+
+// **A binding the part did not keep is read again from the shared events stream** (issue 1966; the lead's ruling, option
+// b): grants_bindings_again asks the part's process, by a person's act recorded as a hand act, to read the seat
+// mesh-broker's events the stream still holds, oldest first, and to keep each of one module's created, recreated and
+// dropped through HearBroker, as if heard now, so a binding dropped since is not brought back. The stream keeps its events
+// for a bounded age: a created older than that is not there, and the answer says so, naming the path then (the seat's
+// list answering each entry's binding, a record extending ADR 0595 §7).
+
+// KeyBindingsAgain is, in StateUserList, the last re-read of one module's bindings: BindingsAgain.
+const KeyBindingsAgain = "bindings-again"
+
+// BrokerHistory reads the seat mesh-broker's events again from the shared events stream.
+type BrokerHistory interface {
+	// Said is every event of the seat the stream still holds, oldest first.
+	Said() ([]SaidEvent, error)
+}
+
+// SaidEvent is one event of the seat mesh-broker as the shared events stream holds it.
+type SaidEvent struct {
+	Subject string    `json:"subject"`
+	Data    []byte    `json:"data"`
+	At      time.Time `json:"at"`
+}
+
+// BindingsAgain is what the last re-read of one module's bindings found: the seat's events read, the local names whose
+// binding it kept (Kept), those it found already kept as said (Already), those a dropped took away (Dropped), the oldest
+// event the stream still holds, and in plain words what it means.
+type BindingsAgain struct {
+	V       int       `json:"v"`
+	Module  string    `json:"module"`
+	By      string    `json:"by"`
+	At      time.Time `json:"at"`
+	Read    int       `json:"read"`
+	Kept    []string  `json:"kept"`
+	Already []string  `json:"already"`
+	Dropped []string  `json:"dropped"`
+	Oldest  time.Time `json:"oldest,omitzero"`
+	Says    string    `json:"says"`
+	Error   string    `json:"error,omitempty"`
+}
+
+// bindingsAgain reads module's bindings again from the seat's events the stream holds, keeps each, and writes what it
+// found to its own state; an error is said in the pass's errors and in the kept result.
+func (p *Part) bindingsAgain(res *Result, module, by string) {
+	out := BindingsAgain{V: 1, Module: module, By: by, At: p.now(), Kept: []string{}, Already: []string{}, Dropped: []string{}}
+	events, err := p.History.Said()
+	if err != nil {
+		out.Error = "the shared events stream could not be read: " + err.Error()
+	}
+	heardCreate := false
+	for _, e := range events {
+		if out.Oldest.IsZero() || (!e.At.IsZero() && e.At.Before(out.Oldest)) {
+			out.Oldest = e.At
+		}
+		name, ok := brokerEvent(e.Subject, p.Brokers())
+		if !ok {
+			continue
+		}
+		var said BrokerEvent
+		if json.Unmarshal(e.Data, &said) != nil || said.Module != module {
+			continue
+		}
+		out.Read++
+		local := firstOf(said.LocalName, said.Local, said.Binding.Local)
+		changed, err := p.HearBroker(e.Subject, e.Data, p.Brokers())
+		if err != nil {
+			out.Error = fmt.Sprintf("the %s of %s could not be kept: %v", name, local, err)
+			break
+		}
+		switch {
+		case name == BrokerDropped && changed:
+			out.Dropped = appendOnce(out.Dropped, local)
+			out.Kept = slices.DeleteFunc(out.Kept, func(l string) bool { return l == local })
+		case name != BrokerDropped:
+			heardCreate = true
+			out.Dropped = slices.DeleteFunc(out.Dropped, func(l string) bool { return l == local })
+			if changed {
+				out.Kept = appendOnce(out.Kept, local)
+				out.Already = slices.DeleteFunc(out.Already, func(l string) bool { return l == local })
+			} else if !slices.Contains(out.Kept, local) {
+				out.Already = appendOnce(out.Already, local)
+			}
+		}
+	}
+	switch {
+	case out.Error != "":
+		out.Says = "the re-read of " + module + " stopped: " + out.Error
+		res.Errors = append(res.Errors, out.Says)
+	case !heardCreate:
+		out.Says = fmt.Sprintf("the shared events stream holds no created or recreated of %s (its oldest event: %s): a created older "+
+			"than the stream keeps is not there, and its binding comes back only by the seat mesh-broker's list answering each "+
+			"entry's binding (a record extending ADR 0595 §7), not by this tool", module, out.Oldest.Format(time.RFC3339))
+	default:
+		out.Says = fmt.Sprintf("read %d of the seat mesh-broker's events of %s again: kept %v, already kept %v, dropped %v; the pass "+
+			"writes them into its memberships", out.Read, module, out.Kept, out.Already, out.Dropped)
+	}
+	if p.Logf != nil {
+		p.Logf("the bindings of %s read again by hand, for %s: %s", module, by, out.Says)
+	}
+	raw, _ := json.Marshal(out)
+	p.changed(res, StateUserList, KeyBindingsAgain, raw)
+}
+
+func appendOnce(list []string, s string) []string {
+	if slices.Contains(list, s) {
+		return list
+	}
+	return append(list, s)
+}
+
+// AskBindingsAgain answers the tool grants_bindings_again: it asks the part's process to read one module's bindings
+// again from the seat mesh-broker's events the shared events stream holds, and records the hand act through record (the
+// seat mesh-hand-acts) first; a module that is no module's name, or an ask without why, is refused before anything is
+// asked. grants_bindings shows what the process found.
+func (p *Part) AskBindingsAgain(caller, module, why string, record func(what, why string) error) (any, error) {
+	if module == "" || strings.ContainsAny(module, ".*> ") {
+		return nil, fmt.Errorf("grants_bindings_again needs one module, by its name: %q is none", module)
+	}
+	if strings.TrimSpace(why) == "" {
+		return nil, errors.New("grants_bindings_again needs why: it is recorded as a hand act")
+	}
+	if record != nil {
+		if err := record(ToolBindingsAgain+" "+module, why); err != nil {
+			return nil, fmt.Errorf("the hand act could not be recorded, so nothing was asked: %w", err)
+		}
+	}
+	ask, _ := json.Marshal(Ask{By: caller, At: p.now(), Bindings: module})
+	rev, err := p.Store.Put(StateUserList, KeyAsked, ask)
+	if err != nil {
+		return nil, fmt.Errorf("the ask could not be written: %w", err)
+	}
+	return map[string]any{"asked": rev, "module": module,
+		"says": "the part's process reads the seat mesh-broker's created, recreated and dropped of " + module + " again from the shared " +
+			"events stream at this ask, and keeps each as if heard now; grants_bindings shows what it kept, what was already kept, " +
+			"and whether the stream still holds its created"}, nil
+}
+
+// lastBindingsAgain is the last re-read kept, when it was of module (or any, for an empty module).
+func (p *Part) lastBindingsAgain(module string) (*BindingsAgain, error) {
+	raw, _, found, err := p.Store.Get(StateUserList, KeyBindingsAgain)
+	if err != nil {
+		return nil, fmt.Errorf("its own %s %s cannot be read: %w", StateUserList, KeyBindingsAgain, err)
+	}
+	if !found {
+		return nil, nil
+	}
+	var b BindingsAgain
+	if err := json.Unmarshal(raw, &b); err != nil {
+		return nil, fmt.Errorf("its own %s %s does not read: %w", StateUserList, KeyBindingsAgain, err)
+	}
+	if module != "" && b.Module != module {
+		return nil, nil
+	}
+	return &b, nil
 }
 
 func sameBinding(a, b membership.BusBinding) bool {

modules/mesh-grants/internal/grants/part.go

@@ -174,6 +174,9 @@ type Part struct {
 	// Say says a condition to the operator: the process's; nil in the tools.
 	Say func(oc.Condition) error
 	Now func() time.Time
+	// History reads the seat mesh-broker's events again from the shared events stream (bindings.go): the process's
+	// connection; nil in the tools, which ask the process.
+	History BrokerHistory
 	// SeatList is the seat list reader, which gates a module whose seats the list has not named (inputs.go, SeatGate); nil
 	// gates none.
 	SeatList SeatGate
@@ -258,6 +261,9 @@ type Ask struct {
 	Consumer string `json:"consumer,omitempty"`
 	// FirstView is, from grants_first_view_again, one first view to ask once more by hand (its state), or AllFirstViews.
 	FirstView string `json:"first-view,omitempty"`
+	// Bindings is, from grants_bindings_again, one module whose bindings the part reads again from the seat mesh-broker's
+	// events the shared events stream still holds (bindings.go, issue 1966).
+	Bindings string `json:"bindings,omitempty"`
 }
 
 // AllFirstViews asks every first view once more.
@@ -298,6 +304,14 @@ func (p *Part) Compose() Result {
 	p.Views.SayUnsaid()
 	in := p.inputs()
 	p.keepBrokers(in)
+	var ask Ask
+	if p.Create != nil || p.Consumers != nil {
+		ask = p.asked()
+	}
+	// A module's bindings read again by hand are kept before the pass reads the kept bindings, so it writes them now.
+	if ask.Bindings != "" && p.History != nil {
+		p.bindingsAgain(&res, ask.Bindings, ask.By)
+	}
 	if err := p.withBound(&in); err != nil {
 		res.Errors = append(res.Errors, err.Error())
 	}
@@ -493,10 +507,6 @@ func (p *Part) Compose() Result {
 	}
 	p.clearFull()
 	held, heldErr := HeldStreams(p.Call)
-	var ask Ask
-	if p.Create != nil || p.Consumers != nil {
-		ask = p.asked()
-	}
 	forced := ask.Assert
 	for _, module := range sortedKeys(in.Manifests) {
 		if !assigned(in, module) {

modules/mesh-grants/internal/grants/tools.go

@@ -33,11 +33,13 @@ const (
 	ToolSeatListAgain = "grants_seat_list_again"
 	// ToolBindings reads the bindings the part keeps from the bus module's events (bindings.go, issue 1966).
 	ToolBindings = "grants_bindings"
+	// ToolBindingsAgain reads one module's bindings again from the seat mesh-broker's events the shared events stream holds.
+	ToolBindingsAgain = "grants_bindings_again"
 )
 
 // Tools is every tool, in the manifest's order.
 var Tools = []string{ToolGrants, ToolMembership, ToolUserList, ToolComposeNow, ToolAssert, ToolAccounts, ToolConsumerMatch,
-	ToolAcceptHashes, ToolFirstViews, ToolFirstViewAgain, ToolSeatList, ToolSeatListAgain, ToolBindings}
+	ToolAcceptHashes, ToolFirstViews, ToolFirstViewAgain, ToolSeatList, ToolSeatListAgain, ToolBindings, ToolBindingsAgain}
 
 // WritesGrants is what grants says of the part's own grants: written once the list the bus loaded carries a build's
 // accounts, and the one key the assigner reads (ADR 0571 clause 9, which changes ADR 0547 clause 5).

modules/mesh-grants/module.json

@@ -62,7 +62,8 @@
     "grants_first_view_again",
     "grants_seat_list",
     "grants_seat_list_again",
-    "grants_bindings"
+    "grants_bindings",
+    "grants_bindings_again"
   ],
   "state": [
     {