Nests: team rooms with core crows and borrowing

- Server: nests API, persistence, core-first picking, borrowed flag
  (built by the backend agent against EVENTS.md; tests pass with -race)
- UI: nests in the sidebar, one feed per nest, header shows the core
  team, New nest dialog, borrowed crows labeled, per-nest waiting count
- start.command: one-click local server in controlled mode (mock crows,
  localhost only, state in .crows/)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UQnSw4RRWp8uqpj3nsnnXF

.gitignore

@@ -5,3 +5,4 @@ node_modules/
 dist/
 /somanycrows
 /web/
+/dist/

README.md

@@ -38,6 +38,21 @@ curl localhost:8080/api/trust
 - UI development: run `crows serve`, then `cd ui && npm run dev` (Vite proxies `/api`). The crow art is `art/crow.svg`; the UI's `CrowView` mirrors `RIVE_CONTRACT.md`, so a Rive-backed view replaces the SVG stand-in later.
 - POST bodies are capped at 64 KB. Static files are served from `./web` when that folder exists.
 
+## Nests
+
+A nest is a room where a team of crows works together. Create one with its core crows; jobs in that nest use the core first and borrow from the rest of the flock when they need more (a murder of 3 in a 2-crow nest borrows one). The Sentry and Elder serve every nest.
+
+```
+curl localhost:8080/api/nests                     # {"roster": [...], "nests": [...]}
+curl -XPOST localhost:8080/api/nests -d '{"name":"Launch copy","crows":["Pepper","Inky"]}'   # 201, nest_id "launch-copy"
+curl -XPOST localhost:8080/api/lists -d '{"text":"- [ ] Should we launch on a Tuesday","nest_id":"launch-copy"}'
+./crows run todo.txt -nest launch-copy
+```
+
+- The default nest is `todo`, with an empty core: crows come from the whole flock and are never "borrowed".
+- `crow.flying` carries `borrowed: true` for a crow from outside the nest's core.
+- Names are 1–40 characters; `nest_id` is the name as a slug and must be unique (409 on a clash). 1–8 roster crows, no repeats, at most 20 nests. Nests are saved in `.crows/nests.json`.
+
 ## How an item flies
 
 1. **Sentry** classifies it: `solo` (one crow), `split` (2–4 subtasks in parallel), or `murder` (3 crows answer independently).

flock.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"slices"
 	"strings"
 	"sync"
 	"time"
@@ -82,22 +83,46 @@ type Flock struct {
 	log   *FlightLog
 	sem   chan struct{}
 
-	mu   sync.Mutex
+	mu     sync.Mutex
-	next int
+	next   int            // rotation through the whole flock (the todo nest)
+	core   map[string]int // per nest: rotation within its core
+	borrow map[string]int // per nest: rotation through crows outside its core
 }
 
 func NewFlock(brain Brain, g Guardrails, log *FlightLog) *Flock {
-	return &Flock{brain: brain, g: g, log: log, sem: make(chan struct{}, g.MaxCrowsInFlight)}
+	return &Flock{
+		brain: brain, g: g, log: log, sem: make(chan struct{}, g.MaxCrowsInFlight),
+		core: map[string]int{}, borrow: map[string]int{},
+	}
 }
 
-// pick rotates through the roster so every crow gets a chance to build a record.
+// pick chooses n crows for a job in a nest. A nest with no core (todo) rotates
-func (f *Flock) pick(n int) []string {
+// through the whole roster so every crow gets a chance to build a record.
+// Otherwise core crows go first (rotating within the core), and any extra
+// crows are borrowed from outside the core (rotating).
+func (f *Flock) pick(nest Nest, n int) []string {
 	f.mu.Lock()
 	defer f.mu.Unlock()
-	out := make([]string, n)
+	out := make([]string, 0, n)
-	for i := range out {
+	if len(nest.Crows) == 0 {
-		out[i] = roster[f.next%len(roster)]
+		for range n {
-		f.next++
+			out = append(out, roster[f.next%len(roster)])
+			f.next++
+		}
+		return out
+	}
+	core := nest.Crows
+	for range min(n, len(core)) {
+		out = append(out, core[f.core[nest.ID]%len(core)])
+		f.core[nest.ID]++
+	}
+	outside := slices.DeleteFunc(slices.Clone(roster), func(c string) bool { return slices.Contains(core, c) })
+	if len(outside) == 0 {
+		outside = core // the whole flock is the core: nobody left to borrow
+	}
+	for len(out) < n {
+		out = append(out, outside[f.borrow[nest.ID]%len(outside)])
+		f.borrow[nest.ID]++
 	}
 	return out
 }
@@ -169,11 +194,11 @@ func (f *Flock) Triage(ctx context.Context, w Watcher, item string, budgets ...*
 	return t, nil
 }
 
-func (f *Flock) Execute(ctx context.Context, w Watcher, item string, t Triage, budgets ...*Budget) (Outcome, error) {
+func (f *Flock) Execute(ctx context.Context, w Watcher, item string, t Triage, nest Nest, budgets ...*Budget) (Outcome, error) {
 	switch t.Mode {
 	case "split":
 		// Split depth is 1: subtasks go straight to crows, never back to the Sentry.
-		crows := f.pick(len(t.Subtasks))
+		crows := f.pick(nest, len(t.Subtasks))
 		reports, err := f.fanOut(ctx, w, crows, t.Subtasks, budgets...)
 		if err != nil {
 			return Outcome{}, err
@@ -181,7 +206,7 @@ func (f *Flock) Execute(ctx context.Context, w Watcher, item string, t Triage, b
 		return f.reconcile(ctx, w, item, crows, t.Subtasks, reports, budgets...)
 	case "murder":
 		n := min(f.g.MurderSize, f.g.MaxCrowsInFlight)
-		crows := f.pick(n)
+		crows := f.pick(nest, n)
 		tasks := make([]string, n)
 		for i := range tasks {
 			tasks[i] = item
@@ -192,7 +217,7 @@ func (f *Flock) Execute(ctx context.Context, w Watcher, item string, t Triage, b
 		}
 		return f.reconcile(ctx, w, item, crows, tasks, reports, budgets...)
 	default:
-		c := f.pick(1)[0]
+		c := f.pick(nest, 1)[0]
 		ans, err := f.ask(ctx, w, c, crowSystem, "TASK: "+item, budgets...)
 		return Outcome{Answer: ans, Crows: []string{c}}, err
 	}

main.go

@@ -36,7 +36,7 @@ func main() {
 func usage() {
 	fmt.Fprintln(os.Stderr, `So Many Crows
 
-  crows run <todo.txt> [-as name]   hand the flock a todo list
+  crows run <todo.txt> [-as name] [-nest id]  hand the flock a todo list
   crows serve [-addr 127.0.0.1:8080] run the web server (API + SSE)
   crows trust                       show trust ledger
   crows log [-n 20]                 show recent flight log entries`)
@@ -46,6 +46,7 @@ func usage() {
 func cmdRun(args []string) {
 	fs := flag.NewFlagSet("run", flag.ExitOnError)
 	as := fs.String("as", defaultRequester(), "requester id")
+	nestID := fs.String("nest", defaultNestID, "nest whose core crows fly first")
 	var pos []string
 	for fs.Parse(args); fs.NArg() > 0; fs.Parse(args) {
 		pos = append(pos, fs.Arg(0))
@@ -62,6 +63,12 @@ func cmdRun(args []string) {
 	flog, err := OpenFlightLog(filepath.Join(dataDir, "flight.jsonl"))
 	must(err)
 	defer flog.Close()
+	nests, err := LoadNests(filepath.Join(dataDir, "nests.json"))
+	must(err)
+	nest, found := nests.Get(*nestID)
+	if !found {
+		must(fmt.Errorf("there is no nest called %q", *nestID))
+	}
 	p := &Pipeline{Ledger: ledger, Log: flog, G: g, Approver: &StdinApprover{in: bufio.NewReader(os.Stdin)}}
 
 	if ok, msg, _ := ledger.Admit(*as, time.Now(), g); !ok {
@@ -86,8 +93,8 @@ func cmdRun(args []string) {
 	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
 	defer stop()
 
-	fmt.Printf("Brain: %s · requester: %s · %d items\n", brain.Name(), *as, len(items))
+	fmt.Printf("Brain: %s · requester: %s · nest: %s · %d items\n", brain.Name(), *as, nest.ID, len(items))
-	l := List{ID: "cli", Requester: *as, Source: todoPath, Items: items}
+	l := List{ID: "cli", Requester: *as, Source: todoPath, Items: items, Nest: nest}
 	results, listBudget := p.Run(ctx, l, &cliEmitter{items: items, seen: map[string]bool{}})
 
 	resultPath := strings.TrimSuffix(todoPath, filepath.Ext(todoPath)) + ".crows.md"

nests.go

@@ -0,0 +1,170 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"slices"
+	"strings"
+	"sync"
+	"unicode/utf8"
+)
+
+// A nest is a room where a team of crows works together. Its core crows are
+// picked first; when a job needs more, the Sentry borrows from the rest of the
+// flock. The Sentry and Elder serve every nest and are never core members.
+type Nest struct {
+	ID    string   `json:"nest_id"`
+	Name  string   `json:"name"`
+	Crows []string `json:"crows"`
+}
+
+const (
+	defaultNestID = "todo"
+	maxNests      = 20 // includes the default nest
+	maxNestName   = 40
+)
+
+// defaultNest has an empty core: its crows come from the whole flock.
+var defaultNest = Nest{ID: defaultNestID, Name: "To do", Crows: []string{}}
+
+// NestError is a rejected nest. Clash means the nest_id is already taken (409);
+// anything else is bad input or too many nests (400).
+type NestError struct {
+	Clash bool
+	Msg   string
+}
+
+func (e *NestError) Error() string { return e.Msg }
+
+func invalid(format string, a ...any) error {
+	return &NestError{Msg: fmt.Sprintf(format, a...)}
+}
+
+// NestStore holds the nests and saves the ones people create to disk.
+type NestStore struct {
+	path string
+	mu   sync.Mutex
+	made []Nest // created nests, in creation order; the default nest is not stored
+}
+
+func LoadNests(path string) (*NestStore, error) {
+	s := &NestStore{path: path}
+	data, err := os.ReadFile(path)
+	if err != nil && !os.IsNotExist(err) {
+		return nil, err
+	}
+	if err == nil {
+		if err := json.Unmarshal(data, &s.made); err != nil {
+			return nil, fmt.Errorf("nests file is unreadable: %w", err)
+		}
+	}
+	return s, nil
+}
+
+// All returns the default nest first, then the others in creation order.
+func (s *NestStore) All() []Nest {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	out := []Nest{copyNest(defaultNest)}
+	for _, n := range s.made {
+		out = append(out, copyNest(n))
+	}
+	return out
+}
+
+// Get finds a nest by ID.
+func (s *NestStore) Get(id string) (Nest, bool) {
+	if id == defaultNestID {
+		return copyNest(defaultNest), true
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for _, n := range s.made {
+		if n.ID == id {
+			return copyNest(n), true
+		}
+	}
+	return Nest{}, false
+}
+
+// Create checks the guardrails, adds the nest, and saves. A rejection is a
+// *NestError; any other error means the save failed.
+func (s *NestStore) Create(name string, crows []string) (Nest, error) {
+	name = strings.TrimSpace(name)
+	if n := utf8.RuneCountInString(name); n < 1 || n > maxNestName {
+		return Nest{}, invalid("A nest name is 1 to %d characters.", maxNestName)
+	}
+	id := slugify(name)
+	if id == "" {
+		return Nest{}, invalid("A nest name needs at least one letter or digit (a-z, 0-9).")
+	}
+	if len(crows) < 1 || len(crows) > len(roster) {
+		return Nest{}, invalid("A nest has 1 to %d crows.", len(roster))
+	}
+	for i, c := range crows {
+		if !slices.Contains(roster, c) {
+			return Nest{}, invalid("%q is not in the flock. Choose from %s.", c, strings.Join(roster, ", "))
+		}
+		if slices.Contains(crows[:i], c) {
+			return Nest{}, invalid("%s is listed twice.", c)
+		}
+	}
+
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if id == defaultNestID || slices.ContainsFunc(s.made, func(n Nest) bool { return n.ID == id }) {
+		return Nest{}, &NestError{Clash: true, Msg: fmt.Sprintf("A nest called %q already exists.", id)}
+	}
+	if 1+len(s.made) >= maxNests {
+		return Nest{}, invalid("The flock keeps at most %d nests.", maxNests)
+	}
+	n := Nest{ID: id, Name: name, Crows: slices.Clone(crows)}
+	s.made = append(s.made, n)
+	if err := s.save(); err != nil {
+		s.made = s.made[:len(s.made)-1]
+		return Nest{}, err
+	}
+	return copyNest(n), nil
+}
+
+// save writes atomically, like the ledger. The caller holds s.mu.
+func (s *NestStore) save() error {
+	data, err := json.MarshalIndent(s.made, "", "  ")
+	if err != nil {
+		return err
+	}
+	if err := os.MkdirAll(filepath.Dir(s.path), 0o755); err != nil {
+		return err
+	}
+	tmp := s.path + ".tmp"
+	if err := os.WriteFile(tmp, data, 0o644); err != nil {
+		return err
+	}
+	return os.Rename(tmp, s.path)
+}
+
+func copyNest(n Nest) Nest {
+	n.Crows = append([]string{}, n.Crows...)
+	return n
+}
+
+// slugify lowercases and keeps a-z and 0-9; every other run of characters
+// becomes one dash, and dashes at the ends are dropped.
+func slugify(name string) string {
+	var sb strings.Builder
+	dash := false
+	for _, r := range strings.ToLower(name) {
+		if (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') {
+			if dash && sb.Len() > 0 {
+				sb.WriteByte('-')
+			}
+			sb.WriteRune(r)
+			dash = false
+		} else {
+			dash = true
+		}
+	}
+	return sb.String()
+}

nests_test.go

@@ -0,0 +1,214 @@
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+	"path/filepath"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestPickCoreFirstThenBorrow(t *testing.T) {
+	f := NewFlock(MockBrain{}, DefaultGuardrails(), nil)
+	nest := Nest{ID: "launch", Crows: []string{"Pepper", "Inky"}}
+
+	// Within the core, picks rotate.
+	if got := f.pick(nest, 1); !slices.Equal(got, []string{"Pepper"}) {
+		t.Fatalf("first solo pick: %v", got)
+	}
+	if got := f.pick(nest, 1); !slices.Equal(got, []string{"Inky"}) {
+		t.Fatalf("second solo pick should rotate within the core: %v", got)
+	}
+
+	// A murder of 3 needs one more than the core: the whole core flies, plus one borrowed.
+	got := f.pick(nest, 3)
+	if !slices.Contains(got, "Pepper") || !slices.Contains(got, "Inky") {
+		t.Fatalf("core crows should fly first: %v", got)
+	}
+	if got[2] != "Hugin" {
+		t.Fatalf("first borrowed crow should be the first roster crow outside the core: %v", got)
+	}
+	// Borrowing rotates too, and never picks a core crow.
+	if got := f.pick(nest, 3); got[2] != "Munin" {
+		t.Fatalf("borrowing should rotate: %v", got)
+	}
+
+	// The todo nest keeps the old whole-flock rotation, unaffected by other nests.
+	if got := f.pick(defaultNest, 3); !slices.Equal(got, roster[:3]) {
+		t.Fatalf("todo nest should rotate the whole roster: %v", got)
+	}
+}
+
+func TestPickWholeFlockCore(t *testing.T) {
+	f := NewFlock(MockBrain{}, DefaultGuardrails(), nil)
+	nest := Nest{ID: "all", Crows: slices.Clone(roster)}
+	got := f.pick(nest, 3)
+	if !slices.Equal(got, roster[:3]) {
+		t.Fatalf("got %v", got)
+	}
+}
+
+func TestNestValidation(t *testing.T) {
+	s, _ := LoadNests(filepath.Join(t.TempDir(), "nests.json"))
+	bad := []struct {
+		name  string
+		crows []string
+	}{
+		{"   ", []string{"Pepper"}},
+		{strings.Repeat("a", 41), []string{"Pepper"}},
+		{"!!!", []string{"Pepper"}},
+		{"No crows", nil},
+		{"Too many", append(slices.Clone(roster), "Hugin")},
+		{"Stranger", []string{"Pepper", "Tweety"}},
+		{"Sentry inside", []string{"Sentry"}},
+		{"Twice", []string{"Pepper", "Pepper"}},
+	}
+	for _, b := range bad {
+		_, err := s.Create(b.name, b.crows)
+		var ne *NestError
+		if err == nil || !errors.As(err, &ne) || ne.Clash {
+			t.Errorf("Create(%q, %v): want invalid, got %v", b.name, b.crows, err)
+		}
+	}
+
+	n, err := s.Create("  Launch -- Copy!  ", []string{"Pepper", "Inky"})
+	if err != nil || n.ID != "launch-copy" || n.Name != "Launch -- Copy!" {
+		t.Fatalf("got %+v, %v", n, err)
+	}
+	if _, err := s.Create(strings.Repeat("a", 40), []string{"Jet"}); err != nil {
+		t.Fatalf("40 characters should be fine: %v", err)
+	}
+	for _, name := range []string{"launch copy", "TODO"} {
+		_, err := s.Create(name, []string{"Jet"})
+		var ne *NestError
+		if !errors.As(err, &ne) || !ne.Clash {
+			t.Errorf("Create(%q): want clash, got %v", name, err)
+		}
+	}
+}
+
+func TestNestsPersistAndCap(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "nests.json")
+	s, _ := LoadNests(path)
+	for i := 1; i < maxNests; i++ { // todo is nest number one
+		if _, err := s.Create(fmt.Sprintf("Nest %d", i), []string{"Soot"}); err != nil {
+			t.Fatalf("nest %d: %v", i, err)
+		}
+	}
+	if _, err := s.Create("One too many", []string{"Soot"}); err == nil {
+		t.Fatal("want the nest cap to refuse")
+	}
+
+	reloaded, err := LoadNests(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	all := reloaded.All()
+	if len(all) != maxNests || all[0].ID != "todo" || all[1].ID != "nest-1" || all[maxNests-1].ID != "nest-19" {
+		t.Fatalf("reload lost order or nests: %d nests, first %v", len(all), all[:2])
+	}
+	if n, ok := reloaded.Get("nest-7"); !ok || !slices.Equal(n.Crows, []string{"Soot"}) {
+		t.Fatalf("Get after reload: %+v %v", n, ok)
+	}
+}
+
+func TestServerNests(t *testing.T) {
+	ts, _ := newTestServer(t, DefaultGuardrails(), time.Minute)
+
+	var got struct {
+		Roster []string `json:"roster"`
+		Nests  []Nest   `json:"nests"`
+	}
+	getJSON(t, ts.URL+"/api/nests", &got)
+	if !slices.Equal(got.Roster, roster) || len(got.Nests) != 1 || got.Nests[0].ID != "todo" || got.Nests[0].Crows == nil {
+		t.Fatalf("GET /api/nests: %+v", got)
+	}
+
+	code, out := post(t, ts.URL+"/api/nests", `{"name":"Launch copy","crows":["Pepper","Inky"]}`)
+	if code != http.StatusCreated || out["nest_id"] != "launch-copy" {
+		t.Fatalf("create: %d %v", code, out)
+	}
+	if code, out := post(t, ts.URL+"/api/nests", `{"name":"launch  COPY","crows":["Jet"]}`); code != http.StatusConflict || out["message"] == nil {
+		t.Fatalf("clash: want 409 with message, got %d %v", code, out)
+	}
+	if code, out := post(t, ts.URL+"/api/nests", `{"name":"Bad","crows":["Elder"]}`); code != http.StatusBadRequest || out["message"] == nil {
+		t.Fatalf("bad crow: want 400 with message, got %d %v", code, out)
+	}
+	if code, _ := post(t, ts.URL+"/api/nests", `{"name":"x","crows":`+strings.Repeat(" ", maxBody)+`[]}`); code != http.StatusRequestEntityTooLarge {
+		t.Fatalf("want 413, got %d", code)
+	}
+	getJSON(t, ts.URL+"/api/nests", &got)
+	if len(got.Nests) != 2 || got.Nests[1].ID != "launch-copy" {
+		t.Fatalf("after create: %+v", got.Nests)
+	}
+
+	if code, out := post(t, ts.URL+"/api/lists", `{"text":"Write a poem","requester":"t","nest_id":"nope"}`); code != http.StatusNotFound || out["message"] == nil {
+		t.Fatalf("unknown nest: want 404 with message, got %d %v", code, out)
+	}
+}
+
+func TestServerBorrowedEvents(t *testing.T) {
+	ts, _ := newTestServer(t, DefaultGuardrails(), time.Minute)
+	post(t, ts.URL+"/api/nests", `{"name":"Launch copy","crows":["Pepper","Inky"]}`)
+	yes := true
+
+	// "should" makes the mock Sentry call a murder of 3: the 2-crow core plus one borrowed.
+	_, out := post(t, ts.URL+"/api/lists", `{"text":"Should we launch on a Tuesday","requester":"t","nest_id":"launch-copy"}`)
+	events, _ := stream(t, ts, out["list_id"].(string), &yes)
+	if events[0].Data["nest_id"] != "launch-copy" {
+		t.Fatalf("list.started nest_id: %v", events[0].Data)
+	}
+	borrowed := flights(t, events)
+	if !slices.Equal(borrowed["Pepper"], []bool{false}) || !slices.Equal(borrowed["Inky"], []bool{false}) ||
+		!slices.Equal(borrowed["Hugin"], []bool{true}) || !slices.Equal(borrowed["Sentry"], []bool{false}) ||
+		!slices.Equal(borrowed["Elder"], []bool{false}) {
+		t.Fatalf("borrowed flags: %v", borrowed)
+	}
+
+	// The todo nest (the default) never borrows.
+	_, out = post(t, ts.URL+"/api/lists", `{"text":"Should we launch on a Tuesday","requester":"t"}`)
+	events, _ = stream(t, ts, out["list_id"].(string), &yes)
+	if events[0].Data["nest_id"] != "todo" {
+		t.Fatalf("default nest_id: %v", events[0].Data)
+	}
+	for crow, flags := range flights(t, events) {
+		if slices.Contains(flags, true) {
+			t.Fatalf("%s borrowed in the todo nest", crow)
+		}
+	}
+}
+
+// flights maps each crow to the borrowed flag of each of its crow.flying events.
+func flights(t *testing.T, events []sseEvent) map[string][]bool {
+	m := map[string][]bool{}
+	for _, e := range events {
+		if e.Name != "crow.flying" {
+			continue
+		}
+		b, ok := e.Data["borrowed"].(bool)
+		if !ok {
+			t.Fatalf("crow.flying without a borrowed bool: %v", e.Data)
+		}
+		c := e.Data["crow"].(string)
+		m[c] = append(m[c], b)
+	}
+	return m
+}
+
+func getJSON(t *testing.T, url string, v any) {
+	resp, err := http.Get(url)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("GET %s: %d", url, resp.StatusCode)
+	}
+	if err := json.NewDecoder(resp.Body).Decode(v); err != nil {
+		t.Fatal(err)
+	}
+}

pipeline.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"slices"
 	"strings"
 	"sync"
 )
@@ -30,6 +31,7 @@ type Approver interface {
 type List struct {
 	ID, Requester, Source string
 	Items                 []string
+	Nest                  Nest // zero value means the todo nest
 	Parallel              bool // fly items at once (web); the command line goes one by one
 }
 
@@ -51,13 +53,16 @@ func itemID(listID string, i int) string { return fmt.Sprintf("%s-%d", listID, i
 
 // Run flies a list and returns per-item results and the list budget.
 func (p *Pipeline) Run(ctx context.Context, l List, em Emitter) ([]itemResult, *Budget) {
+	if l.Nest.ID == "" {
+		l.Nest = defaultNest
+	}
 	listBudget := &Budget{name: "list", limit: p.G.TokenBudgetPerList}
 	items := make([]map[string]any, len(l.Items))
 	for i, text := range l.Items {
 		items[i] = map[string]any{"item_id": itemID(l.ID, i), "text": text}
 	}
 	p.Log.Write(Event{Kind: "list", Requester: l.Requester, Note: fmt.Sprintf("%s (%d items)", l.Source, len(l.Items))})
-	em.Emit("list.started", map[string]any{"items": items, "requester": l.Requester})
+	em.Emit("list.started", map[string]any{"items": items, "requester": l.Requester, "nest_id": l.Nest.ID})
 
 	results := make([]itemResult, len(l.Items))
 	if l.Parallel {
@@ -89,7 +94,7 @@ func (p *Pipeline) item(ctx context.Context, l List, i int, listBudget *Budget,
 		em.Emit("item.skipped", map[string]any{"item_id": id, "reason": reason})
 		return r
 	}
-	w := &itemWatcher{em: em, itemID: id}
+	w := &itemWatcher{em: em, itemID: id, core: l.Nest.Crows}
 	itemBudget := &Budget{name: "item", limit: p.G.TokenBudgetPerItem}
 
 	t, err := p.Flock.Triage(ctx, w, item, itemBudget, listBudget)
@@ -115,7 +120,7 @@ func (p *Pipeline) item(ctx context.Context, l List, i int, listBudget *Budget,
 		em.Emit("verdict", map[string]any{"item_id": id, "target": "triage", "verdict": "auto"})
 	}
 
-	out, err := p.Flock.Execute(ctx, w, item, t, itemBudget, listBudget)
+	out, err := p.Flock.Execute(ctx, w, item, t, l.Nest, itemBudget, listBudget)
 	if err != nil {
 		return skip("flight failed: " + err.Error())
 	}
@@ -173,10 +178,14 @@ func (p *Pipeline) save() {
 type itemWatcher struct {
 	em     Emitter
 	itemID string
+	core   []string // the nest's core crows; empty for todo
 }
 
+// Flying marks a crow borrowed when the nest has a core and the crow is a
+// roster crow outside it. The Sentry and Elder are never borrowed.
 func (w *itemWatcher) Flying(crow string) {
-	w.em.Emit("crow.flying", map[string]any{"item_id": w.itemID, "crow": crow})
+	borrowed := len(w.core) > 0 && slices.Contains(roster, crow) && !slices.Contains(w.core, crow)
+	w.em.Emit("crow.flying", map[string]any{"item_id": w.itemID, "crow": crow, "borrowed": borrowed})
 }
 
 func (w *itemWatcher) Landed(crow string, tokens int, err error) {

server.go

@@ -31,12 +31,13 @@ type Server struct {
 	p        *Pipeline
 	approver *WebApprover
 	hub      *Hub
+	nests    *NestStore
 	ctx      context.Context // cancelled on shutdown; lists and streams end with it
 	beat     time.Duration
 }
 
-func NewServer(ctx context.Context, p *Pipeline, approver *WebApprover) *Server {
+func NewServer(ctx context.Context, p *Pipeline, approver *WebApprover, nests *NestStore) *Server {
-	return &Server{p: p, approver: approver, hub: NewHub(), ctx: ctx, beat: heartbeat}
+	return &Server{p: p, approver: approver, hub: NewHub(), nests: nests, ctx: ctx, beat: heartbeat}
 }
 
 func (s *Server) Handler() http.Handler {
@@ -45,6 +46,8 @@ func (s *Server) Handler() http.Handler {
 	mux.HandleFunc("GET /api/events", s.events)
 	mux.HandleFunc("POST /api/verdicts", s.postVerdict)
 	mux.HandleFunc("GET /api/trust", s.trust)
+	mux.HandleFunc("GET /api/nests", s.getNests)
+	mux.HandleFunc("POST /api/nests", s.postNest)
 	if st, err := os.Stat(webDir); err == nil && st.IsDir() {
 		mux.Handle("GET /", http.FileServer(http.Dir(webDir)))
 	} else {
@@ -67,13 +70,15 @@ func cmdServe(args []string) {
 	flog, err := OpenFlightLog(filepath.Join(dataDir, "flight.jsonl"))
 	must(err)
 	defer flog.Close()
+	nests, err := LoadNests(filepath.Join(dataDir, "nests.json"))
+	must(err)
 
 	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
 	defer stop()
 	brain := NewBrain()
 	approver := NewWebApprover(*timeout)
 	p := &Pipeline{Flock: NewFlock(brain, g, flog), Ledger: ledger, Log: flog, G: g, Approver: approver}
-	s := NewServer(ctx, p, approver)
+	s := NewServer(ctx, p, approver, nests)
 
 	srv := &http.Server{Addr: *addr, Handler: s.Handler(), ReadHeaderTimeout: 10 * time.Second}
 	go func() {
@@ -120,10 +125,19 @@ func (s *Server) postList(w http.ResponseWriter, r *http.Request) {
 	var body struct {
 		Text      string `json:"text"`
 		Requester string `json:"requester"`
+		NestID    string `json:"nest_id"`
 	}
 	if !decode(w, r, &body) {
 		return
 	}
+	if body.NestID == "" {
+		body.NestID = defaultNestID
+	}
+	nest, found := s.nests.Get(body.NestID)
+	if !found {
+		httpError(w, http.StatusNotFound, fmt.Sprintf("There is no nest called %q.", body.NestID))
+		return
+	}
 	if body.Requester == "" {
 		body.Requester, _, _ = net.SplitHostPort(r.RemoteAddr)
 	}
@@ -157,7 +171,7 @@ func (s *Server) postList(w http.ResponseWriter, r *http.Request) {
 
 	id := newListID()
 	s.hub.Open(id, body.Requester)
-	l := List{ID: id, Requester: body.Requester, Source: "web", Items: items, Parallel: true}
+	l := List{ID: id, Requester: body.Requester, Source: "web", Items: items, Nest: nest, Parallel: true}
 	go s.p.Run(s.ctx, l, s.hub.Emitter(id))
 	writeJSON(w, http.StatusAccepted, map[string]string{"list_id": id})
 }
@@ -253,3 +267,29 @@ func (s *Server) trust(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 	w.Write(data)
 }
+
+func (s *Server) getNests(w http.ResponseWriter, r *http.Request) {
+	writeJSON(w, http.StatusOK, map[string]any{"roster": roster, "nests": s.nests.All()})
+}
+
+func (s *Server) postNest(w http.ResponseWriter, r *http.Request) {
+	var body struct {
+		Name  string   `json:"name"`
+		Crows []string `json:"crows"`
+	}
+	if !decode(w, r, &body) {
+		return
+	}
+	n, err := s.nests.Create(body.Name, body.Crows)
+	var bad *NestError
+	switch {
+	case errors.As(err, &bad) && bad.Clash:
+		httpError(w, http.StatusConflict, bad.Msg)
+	case errors.As(err, &bad):
+		httpError(w, http.StatusBadRequest, bad.Msg)
+	case err != nil:
+		httpError(w, http.StatusInternalServerError, "could not save the nest: "+err.Error())
+	default:
+		writeJSON(w, http.StatusCreated, n)
+	}
+}

server_test.go

@@ -93,10 +93,14 @@ func newTestServer(t *testing.T, g Guardrails, timeout time.Duration) (*httptest
 		t.Fatal(err)
 	}
 	t.Cleanup(func() { flog.Close() })
+	nests, err := LoadNests(filepath.Join(dir, "nests.json"))
+	if err != nil {
+		t.Fatal(err)
+	}
 	ctx, cancel := context.WithCancel(context.Background())
 	approver := NewWebApprover(timeout)
 	p := &Pipeline{Flock: NewFlock(MockBrain{}, g, flog), Ledger: ledger, Log: flog, G: g, Approver: approver}
-	s := NewServer(ctx, p, approver)
+	s := NewServer(ctx, p, approver, nests)
 	s.beat = 20 * time.Millisecond
 	ts := httptest.NewServer(s.Handler())
 	t.Cleanup(func() { cancel(); ts.Close() })

start.command

@@ -0,0 +1,22 @@
+#!/bin/bash
+# So Many Crows: local test server.
+# Double-click to start. Close this window (or Ctrl-C) to stop.
+#
+# Controlled by default:
+#   - offline mock crows (no API key used, no cost, no network calls)
+#   - listens on this Mac only (127.0.0.1:8080)
+#   - all state lives in this folder's .crows/ (delete it to start fresh)
+# From Terminal, `./start.command --real` uses real Claude crows (needs ANTHROPIC_API_KEY).
+cd "$(dirname "$0")" || exit 1
+xattr -d com.apple.quarantine ./crows 2>/dev/null
+chmod +x ./crows
+if [ "$1" != "--real" ]; then
+  unset ANTHROPIC_API_KEY
+  echo "Controlled mode: offline mock crows."
+fi
+if lsof -iTCP:8080 -sTCP:LISTEN >/dev/null 2>&1; then
+  echo "Something is already using port 8080. Stop it first."
+  exit 1
+fi
+(sleep 1; open "http://127.0.0.1:8080") &
+exec ./crows serve -addr 127.0.0.1:8080

ui/index.html

@@ -17,6 +17,9 @@
       </nav>
       <aside class="side" aria-label="The flock">
         <div class="brand">So Many Crows</div>
+        <h2>Nests</h2>
+        <nav class="nests" id="nests" aria-label="Nests"></nav>
+        <button class="new-nest" id="new-nest" type="button">+ New nest</button>
         <h2>The flock</h2>
         <div class="roster" id="roster"></div>
         <label class="who">You are <input id="requester" maxlength="40" autocomplete="off" /></label>
@@ -24,11 +27,11 @@
 
       <section class="room">
         <header class="room-head">
-          <h1># todo</h1>
+          <h1 id="room-title"># todo</h1>
-          <p class="room-sub">Hand the flock a list. The Sentry sorts it, crows fly, you judge.</p>
+          <p class="room-sub" id="room-sub">The whole flock roosts here. Hand it a list: the Sentry sorts it, crows fly, you judge.</p>
         </header>
 
-        <ol class="feed" id="feed" aria-live="polite"></ol>
+        <div class="feeds" id="feeds"></div>
         <p class="typing" id="typing" aria-live="polite"></p>
 
         <form class="composer" id="composer">
@@ -39,6 +42,22 @@
         </form>
       </section>
     </div>
+    <dialog class="nest-dialog inked" id="nest-dialog">
+      <form method="dialog" id="nest-form">
+        <h2>New nest</h2>
+        <p class="dialog-sub">A room where a team of crows works together. The Sentry can borrow other crows when a job needs more hands.</p>
+        <label class="dialog-field">Name <input id="nest-name" maxlength="40" required autocomplete="off" placeholder="Launch copy" /></label>
+        <fieldset class="pick">
+          <legend>Core crows</legend>
+          <div class="pick-grid" id="nest-crows"></div>
+        </fieldset>
+        <p class="err" id="nest-err"></p>
+        <div class="dialog-actions">
+          <button class="btn btn-no inked" value="cancel" formnovalidate>Cancel</button>
+          <button class="btn btn-go inked" id="nest-create" value="create">Build the nest</button>
+        </div>
+      </form>
+    </dialog>
     <script type="module" src="/src/main.ts"></script>
   </body>
 </html>

ui/src/api.ts

@@ -5,11 +5,11 @@ export type PostListResult =
   | { ok: false; pranked: true; message: string; cooldownS: number }
   | { ok: false; pranked: false; message: string };
 
-export async function postList(text: string, requester: string): Promise<PostListResult> {
+export async function postList(text: string, requester: string, nestId: string): Promise<PostListResult> {
   const res = await fetch("/api/lists", {
     method: "POST",
     headers: { "Content-Type": "application/json" },
-    body: JSON.stringify({ text, requester }),
+    body: JSON.stringify({ text, requester, nest_id: nestId }),
   });
   const body = await res.json().catch(() => ({}));
   if (res.ok) return { ok: true, listId: String(body.list_id) };
@@ -43,3 +43,35 @@ export async function getTrust(): Promise<TrustLevels> {
 export function listEvents(listId: string): EventSource {
   return new EventSource(`/api/events?list_id=${encodeURIComponent(listId)}`);
 }
+
+// ---------- nests ----------
+export type Nest = { nestId: string; name: string; crows: string[] };
+export type Nests = { roster: string[]; nests: Nest[] };
+
+const DEFAULT_ROSTER = ["Hugin", "Munin", "Corvina", "Soot", "Pepper", "Inky", "Edgar", "Jet"];
+
+export async function getNests(): Promise<Nests> {
+  try {
+    const res = await fetch("/api/nests");
+    if (!res.ok) throw new Error(String(res.status));
+    const body = await res.json();
+    return {
+      roster: (body.roster ?? DEFAULT_ROSTER).map(String),
+      nests: (body.nests ?? []).map((n: any) => ({ nestId: String(n.nest_id), name: String(n.name), crows: (n.crows ?? []).map(String) })),
+    };
+  } catch {
+    // A server without nests still has the default room.
+    return { roster: DEFAULT_ROSTER, nests: [{ nestId: "todo", name: "todo", crows: [] }] };
+  }
+}
+
+export async function createNest(name: string, crows: string[]): Promise<Nest> {
+  const res = await fetch("/api/nests", {
+    method: "POST",
+    headers: { "Content-Type": "application/json" },
+    body: JSON.stringify({ name, crows }),
+  });
+  const body = await res.json().catch(() => ({}));
+  if (!res.ok) throw new Error(String(body.message ?? `Couldn't build that nest (${res.status}).`));
+  return { nestId: String(body.nest_id), name: String(body.name), crows: (body.crows ?? []).map(String) };
+}

ui/src/main.ts

@@ -1,11 +1,12 @@
 import "./style.css";
-import { getTrust, listEvents, postList, postVerdict, type TrustLevels } from "./api";
+import { createNest, getNests, getTrust, listEvents, postList, postVerdict, type Nest, type TrustLevels } from "./api";
 import { crowAvatar, svgCrow, type CrowView, type Role } from "./crow";
 
 // ---------- page ----------
 const $ = <T extends HTMLElement>(id: string) => document.getElementById(id) as T;
 const roster = $<HTMLDivElement>("roster");
-const feed = $<HTMLOListElement>("feed");
+const feedsBox = $<HTMLDivElement>("feeds");
+const nestNav = $<HTMLElement>("nests");
 const typing = $<HTMLParagraphElement>("typing");
 const form = $<HTMLFormElement>("composer");
 const listInput = $<HTMLTextAreaElement>("list");
@@ -110,16 +111,70 @@ function fmtTime(ts?: string) {
   return isNaN(+d) ? "" : d.toLocaleTimeString([], { hour: "numeric", minute: "2-digit" });
 }
 
-function append(li: HTMLLIElement) {
+// ---------- nests: one room (and one feed) per team ----------
+type NestRoom = Nest & { feed: HTMLOListElement; link: HTMLButtonElement; count: HTMLSpanElement };
+const nests = new Map<string, NestRoom>();
+let flockNames: string[] = [];
+let current = "todo";
+const roomTitle = $<HTMLHeadingElement>("room-title");
+const roomSub = $<HTMLParagraphElement>("room-sub");
+const roomTab = $<HTMLButtonElement>("tab-room");
+
+function addNest(n: Nest): NestRoom {
+  const feed = el("ol", "feed");
+  feed.setAttribute("aria-live", "polite");
+  feed.hidden = true;
+  feedsBox.append(feed);
+  const link = el("button", "nest-link");
+  link.type = "button";
+  const count = el("span", "nest-count");
+  link.append(el("span", "nest-name", `# ${n.name}`), count);
+  link.addEventListener("click", () => { selectNest(n.nestId); showView("room"); });
+  nestNav.append(link);
+  const room = { ...n, feed, link, count };
+  nests.set(n.nestId, room);
+  return room;
+}
+
+function nest(id: string): NestRoom {
+  return nests.get(id) ?? nests.get("todo")!;
+}
+
+function selectNest(id: string) {
+  current = nest(id).nestId;
+  for (const r of nests.values()) {
+    r.feed.hidden = r.nestId !== current;
+    r.link.setAttribute("aria-current", String(r.nestId === current));
+  }
+  const r = nest(current);
+  roomTitle.textContent = `# ${r.name}`;
+  roomSub.textContent = r.crows.length
+    ? `Core crows: ${r.crows.join(", ")}. The Sentry borrows others when a job needs more hands.`
+    : "The whole flock roosts here. Hand it a list: the Sentry sorts it, crows fly, you judge.";
+  roomTab.textContent = `# ${r.name}`;
+  r.feed.scrollTop = r.feed.scrollHeight;
+  renderTyping();
+}
+
+// Red count on each nest: questions waiting on you in that room.
+function renderNestCounts() {
+  for (const r of nests.values()) {
+    const n = r.feed.querySelectorAll(".msg.asking").length;
+    r.count.textContent = n ? String(n) : "";
+  }
+}
+
+function append(li: HTMLLIElement, nestId: string) {
+  const feed = nest(nestId).feed;
   const stick = feed.scrollHeight - feed.scrollTop - feed.clientHeight < 120;
   feed.append(li);
   if (stick) feed.scrollTop = feed.scrollHeight;
 }
 
-function post(author: string, parts: Node[], ts?: string): Msg {
+function post(author: string, parts: Node[], ts: string | undefined, nestId: string): Msg {
   const li = el("li", "msg");
   li.dataset.author = author;
-  const last = feed.lastElementChild as HTMLElement | null;
+  const last = nest(nestId).feed.lastElementChild as HTMLElement | null;
   if (last?.dataset.author === author) li.classList.add("cont");
   let avatar: Element;
   if (author === "you") {
@@ -141,14 +196,14 @@ function post(author: string, parts: Node[], ts?: string): Msg {
   const main = el("div", "msg-main");
   main.append(head, body, actions, reactions);
   li.append(avatar, main);
-  append(li);
+  append(li, nestId);
   return { li, body, actions, reactions };
 }
 
-function note(text: string, kind = "") {
+function note(text: string, nestId: string, kind = "") {
   const li = el("li", `msg system ${kind}`.trim());
   li.append(el("p", "", text));
-  append(li);
+  append(li, nestId);
 }
 
 function re(text: string) {
@@ -160,7 +215,7 @@ function react(m: Msg, text: string, kind: string) {
 }
 
 // ---------- per-item state ----------
-type Item = { text: string; crows: string[]; taskType: string; triage?: Msg; answer?: Msg };
+type Item = { text: string; nest: string; crows: string[]; borrowed: Set<string>; taskType: string; triage?: Msg; answer?: Msg };
 const items = new Map<string, Item>();
 
 function ask(m: Msg, itemId: string, target: "triage" | "output") {
@@ -183,12 +238,14 @@ function ask(m: Msg, itemId: string, target: "triage" | "output") {
     });
   }
   m.actions.append(yes, no, err);
+  renderNestCounts();
 }
 
 // ---------- who's flying ----------
 const flying = new Set<string>();
+let flyingNest = "";
 function renderTyping() {
-  const names = [...flying];
+  const names = flyingNest === current ? [...flying] : [];
   if (names.length === 0) { typing.textContent = ""; return; }
   const who = names.length === 1 ? names[0]
     : names.length === 2 ? `${names[0]} and ${names[1]}`
@@ -203,12 +260,14 @@ const LEVELS = ["stranger", "regular", "trusted"];
 
 const handlers: Record<string, (d: Payload) => void> = {
   "list.started": (d) => {
+    const nestId = nests.has(d.nest_id) ? d.nest_id : sendingNest;
+    flyingNest = nestId;
     const ol = el("ol", "list");
     for (const it of d.items ?? []) {
-      items.set(it.item_id, { text: it.text, crows: [], taskType: "other" });
+      items.set(it.item_id, { text: it.text, nest: nestId, crows: [], borrowed: new Set(), taskType: "other" });
       ol.append(el("li", "", it.text));
     }
-    post("you", [ol], d.ts);
+    post("you", [ol], d.ts, nestId);
     crow("Sentry").setPose("perched");
     const n = (d.items ?? []).length;
     update("Sentry", `Got a list of ${n} item${n === 1 ? "" : "s"}`, d.ts);
@@ -225,7 +284,7 @@ const handlers: Record<string, (d: Payload) => void> = {
       for (const s of d.subtasks) ul.append(el("li", "", s));
       parts.push(ul);
     }
-    it.triage = post("Sentry", parts, d.ts);
+    it.triage = post("Sentry", parts, d.ts, it.nest);
     showTrust("Sentry", d.task_type);
     if (d.needs_approval) {
       crow("Sentry").setPose("waiting");
@@ -242,8 +301,10 @@ const handlers: Record<string, (d: Payload) => void> = {
     if (it && d.crow !== "Sentry") showTrust(d.crow, it.taskType);
     crow(d.crow).setPose("flying");
     if (it) {
+      if (d.borrowed) it.borrowed.add(d.crow);
       const doing = d.crow === "Sentry" ? "Sorting" : d.crow === "Elder" ? "Merging reports on" : "Flying";
-      update(d.crow, `${doing}${doing === "Flying" ? ":" : ""} ${q(it.text)}`, d.ts);
+      const where = d.borrowed ? ` (borrowed for # ${nest(it.nest).name})` : "";
+      update(d.crow, `${doing}${where}${doing === "Flying" ? ":" : ""} ${q(it.text)}`, d.ts);
     }
     flying.add(d.crow);
     renderTyping();
@@ -265,8 +326,9 @@ const handlers: Record<string, (d: Payload) => void> = {
     const author = it.crows.includes("Elder") ? "Elder" : it.crows[0] ?? "Elder";
     const parts: Node[] = [re(it.text), el("p", "answer", d.answer)];
     const helpers = it.crows.filter((n) => n !== "Elder");
-    if (author === "Elder" && helpers.length) parts.push(el("p", "with", `from ${helpers.join(", ")}`));
+    const named = helpers.map((n) => (it.borrowed.has(n) ? `${n} (borrowed)` : n));
-    it.answer = post(author, parts, d.ts);
+    if (author === "Elder" && helpers.length) parts.push(el("p", "with", `from ${named.join(", ")}`));
+    it.answer = post(author, parts, d.ts, it.nest);
     if (d.needs_approval) {
       for (const n of it.crows) {
         crow(n).setPose("waiting");
@@ -292,6 +354,7 @@ const handlers: Record<string, (d: Payload) => void> = {
       };
       const [text, kind] = label[d.verdict] ?? [d.verdict, ""];
       react(m, text, kind);
+      renderNestCounts();
     }
     if (d.target === "triage" && d.verdict === "auto") return; // a trusted Sentry just keeps going
     const word: Record<string, string> = { approved: "Approved", rejected: "Rejected", auto: "Accepted (trusted)", timeout: "Timed out" };
@@ -308,19 +371,20 @@ const handlers: Record<string, (d: Payload) => void> = {
     const what = String(d.task_type).replace("triage/", "sorting ");
     const up = d.to > d.from;
     if (d.holder === "flock") {
-      note(`The flock ${up ? "earned" : "dropped to"} “${LEVELS[d.to]}” on ${what}.`, up ? "sparkle" : "");
+      note(`The flock ${up ? "earned" : "dropped to"} “${LEVELS[d.to]}” on ${what}.`, flyingNest || current, up ? "sparkle" : "");
       return;
     }
     const c = crow(d.holder);
     c.setTrust(d.to);
     c.fire(up ? "levelUp" : "levelDown");
     update(d.holder, `${up ? "Leveled up to" : "Dropped to"} ${LEVELS[d.to]} on ${what}`, d.ts, up ? "good" : "bad");
-    note(`${d.holder} ${up ? "leveled up to" : "dropped to"} “${LEVELS[d.to]}” on ${what}.`, up ? "sparkle" : "");
+    note(`${d.holder} ${up ? "leveled up to" : "dropped to"} “${LEVELS[d.to]}” on ${what}.`, flyingNest || current, up ? "sparkle" : "");
   },
 
   "item.skipped": (d) => {
     const it = items.get(d.item_id);
-    note(`Skipped “${it?.text ?? d.item_id}”: ${d.reason}.`);
+    note(`Skipped “${it?.text ?? d.item_id}”: ${d.reason}.`, it?.nest ?? flyingNest ?? current);
+    renderNestCounts();
     for (const n of it?.crows ?? []) crow(n).setPose("perched");
     update("Sentry", `Skipped ${q(it?.text ?? d.item_id)}`, d.ts, "bad");
   },
@@ -331,7 +395,8 @@ const handlers: Record<string, (d: Payload) => void> = {
     for (const t of tiles.values()) { t.view.setPose("perched"); t.view.fire("cheer"); }
     flying.clear();
     renderTyping();
-    note(`List done. The flock used ${Number(d.tokens_used).toLocaleString()} of ${Number(d.token_budget).toLocaleString()} tokens.`);
+    note(`List done. The flock used ${Number(d.tokens_used).toLocaleString()} of ${Number(d.token_budget).toLocaleString()} tokens.`, flyingNest || current);
+    flyingNest = "";
     source?.close();
     source = null;
     sendBtn.disabled = false;
@@ -343,7 +408,7 @@ let cooldownTimer = 0;
 const sendLabel = sendBtn.textContent ?? "Send";
 function prank(message: string, cooldownS: number) {
   crow("Sentry").fire("prank");
-  post("Sentry", [el("p", "", message)]);
+  post("Sentry", [el("p", "", message)], undefined, current);
   update("Sentry", "Left a gift on someone's windshield", undefined, "bad");
   let left = Math.max(0, Math.round(cooldownS));
   clearInterval(cooldownTimer);
@@ -362,6 +427,7 @@ function prank(message: string, cooldownS: number) {
 }
 
 // ---------- send a list ----------
+let sendingNest = "todo";
 form.addEventListener("submit", async (e) => {
   e.preventDefault();
   const text = listInput.value.trim();
@@ -369,13 +435,14 @@ form.addEventListener("submit", async (e) => {
   const requester = requesterInput.value.trim() || "anonymous";
   store.set("requester", requester);
   sendBtn.disabled = true;
+  sendingNest = current;
 
-  const res = await postList(text, requester).catch(() => ({ ok: false as const, pranked: false as const, message: "Can't reach the flock. Is `crows serve` running?" }));
+  const res = await postList(text, requester, current).catch(() => ({ ok: false as const, pranked: false as const, message: "Can't reach the flock. Is `crows serve` running?" }));
   if (!res.ok) {
     if (res.pranked) {
       prank(res.message, res.cooldownS); // re-enables the button when the cooldown ends
     } else {
-      note(res.message);
+      note(res.message, current);
       sendBtn.disabled = false;
     }
     return;
@@ -392,16 +459,68 @@ form.addEventListener("submit", async (e) => {
   }
 });
 
-// Phone tabs: the channel or the flock.
+// ---------- phone tabs: the room or the roost (nests + flock) ----------
 const app = document.getElementById("app")!;
-for (const [id, view] of [["tab-room", "room"], ["tab-flock", "flock"]] as const) {
+function showView(view: "room" | "flock") {
-  document.getElementById(id)!.addEventListener("click", () => {
+  app.dataset.view = view;
-    app.dataset.view = view;
+  for (const t of document.querySelectorAll<HTMLButtonElement>(".tab")) {
-    for (const t of document.querySelectorAll<HTMLButtonElement>(".tab")) t.setAttribute("aria-pressed", String(t.id === id));
+    t.setAttribute("aria-pressed", String(t.id === (view === "room" ? "tab-room" : "tab-flock")));
-    if (view === "room") feed.scrollTop = feed.scrollHeight;
+  }
-  });
+  if (view === "room") nest(current).feed.scrollTop = nest(current).feed.scrollHeight;
 }
+roomTab.addEventListener("click", () => showView("room"));
+$<HTMLButtonElement>("tab-flock").addEventListener("click", () => showView("flock"));
 
-// The Sentry is always on watch, and says hello.
+// ---------- new nest dialog ----------
+const dialog = $<HTMLDialogElement>("nest-dialog");
+const nestForm = $<HTMLFormElement>("nest-form");
+const nestName = $<HTMLInputElement>("nest-name");
+const nestCrows = $<HTMLDivElement>("nest-crows");
+const nestErr = $<HTMLParagraphElement>("nest-err");
+
+$<HTMLButtonElement>("new-nest").addEventListener("click", () => {
+  nestErr.textContent = "";
+  nestName.value = "";
+  nestCrows.replaceChildren();
+  for (const name of flockNames) {
+    const label = el("label", "pick-crow");
+    const box = el("input");
+    box.type = "checkbox";
+    box.value = name;
+    label.append(box, crowAvatar("crow"), el("span", "", name));
+    nestCrows.append(label);
+  }
+  dialog.showModal();
+  nestName.focus();
+});
+
+nestForm.addEventListener("submit", async (e) => {
+  const submitter = (e as SubmitEvent).submitter as HTMLButtonElement | null;
+  if (submitter?.value !== "create") return; // Cancel closes the dialog
+  e.preventDefault();
+  const name = nestName.value.trim();
+  const crows = [...nestCrows.querySelectorAll<HTMLInputElement>("input:checked")].map((b) => b.value);
+  if (!name) { nestErr.textContent = "Give the nest a name."; return; }
+  if (!crows.length) { nestErr.textContent = "Pick at least one crow for the core team."; return; }
+  try {
+    const n = await createNest(name, crows);
+    addNest(n);
+    dialog.close();
+    selectNest(n.nestId);
+    showView("room");
+    post("Sentry", [el("p", "", `New nest. Core crows: ${n.crows.join(", ")}. I'll borrow others when a job needs more hands.`)], undefined, n.nestId);
+  } catch (err) {
+    nestErr.textContent = (err as Error).message;
+  }
+});
+
+// ---------- start: load the nests, open # todo, the Sentry says hello ----------
 crow("Sentry");
-post("Sentry", [el("p", "", "Caw. Send me a todo list, one item per line. I'll sort it, the flock will fly it, and you judge the results.")]);
+(async () => {
+  const data = await getNests();
+  flockNames = data.roster;
+  if (!data.nests.some((n) => n.nestId === "todo")) data.nests.unshift({ nestId: "todo", name: "todo", crows: [] });
+  for (const n of data.nests) addNest(n);
+  selectNest("todo");
+  post("Sentry", [el("p", "", "Caw. Send me a todo list, one item per line. I'll sort it, the flock will fly it, and you judge the results.")], undefined, "todo");
+})();

ui/src/style.css

@@ -73,6 +73,47 @@ body { margin: 0; background: var(--paper); color: var(--ink); font: 500 17px/1.
 }
 .who input:focus { outline: none; border-bottom-width: 3px; }
 
+/* ---------- nests: rooms, like channels ---------- */
+.nests { display: flex; flex-direction: column; gap: 2px; }
+.nest-link {
+  display: flex; align-items: center; justify-content: space-between; gap: 8px; width: 100%;
+  padding: 8px 10px; border: 0; border-radius: var(--corner); background: none; cursor: pointer;
+  font: 400 17px/1.2 var(--display); color: var(--muted); text-align: left;
+}
+.nest-link[aria-current="true"] { color: var(--ink); background: rgb(28 25 21 / 0.06); }
+.nest-link:focus-visible { outline: none; text-decoration: underline 2px; text-underline-offset: 4px; }
+.nest-count:not(:empty) {
+  padding: 0 7px; border-radius: 999px; background: var(--red); color: var(--paper); font: 700 12px/1.4 var(--body);
+}
+.new-nest {
+  align-self: flex-start; margin: 2px 4px 6px; padding: 4px 6px; border: 0; background: none; cursor: pointer;
+  font: italic 500 15px/1.2 var(--body); color: var(--muted);
+}
+.new-nest:hover { color: var(--ink); }
+.new-nest:focus-visible { outline: none; text-decoration: underline 2px; text-underline-offset: 4px; }
+
+/* ---------- new nest dialog: a card on the page, no outline ---------- */
+.nest-dialog { width: min(440px, calc(100vw - 32px)); padding: 0; color: var(--ink); overflow: visible; }
+.nest-dialog::backdrop { background: rgb(28 25 21 / 0.25); }
+.nest-dialog form { padding: 22px 22px 18px; }
+.nest-dialog h2 { margin: 0; font: 400 24px/1.1 var(--display); }
+.dialog-sub { margin: 6px 0 16px; color: var(--muted); font-style: italic; font-size: 15px; }
+.dialog-field { display: block; color: var(--muted); font-style: italic; font-size: 15px; }
+.dialog-field input {
+  display: block; width: 100%; margin-top: 4px; padding: 2px 0; font: 500 18px var(--body); color: var(--ink);
+  background: transparent; border: 0; border-bottom: 2px solid var(--ink);
+}
+.dialog-field input:focus { outline: none; border-bottom-width: 3px; }
+.pick { margin: 18px 0 0; padding: 0; border: 0; }
+.pick legend { padding: 0; color: var(--muted); font-style: italic; font-size: 15px; }
+.pick-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 4px; margin-top: 8px; }
+.pick-crow { display: flex; align-items: center; gap: 10px; padding: 6px 8px; border-radius: var(--corner); cursor: pointer; font: 400 16px var(--display); }
+.pick-crow:has(input:checked) { background: rgb(28 25 21 / 0.07); }
+.pick-crow input { accent-color: var(--ink); width: 16px; height: 16px; margin: 0; }
+.pick-crow .avatar { width: 30px; height: 28px; margin: 0; }
+.dialog-actions { display: flex; justify-content: flex-end; gap: 12px; margin-top: 18px; }
+.nest-dialog .err { margin: 10px 0 0; }
+
 /* ---------- roster: one list tile per crow, newest update on top ---------- */
 .roster { display: flex; flex-direction: column; gap: 6px; }
 .tile {
@@ -146,7 +187,9 @@ body { margin: 0; background: var(--paper); color: var(--ink); font: 500 17px/1.
   -webkit-mask-image: linear-gradient(rgb(0 0 0 / 0.55), transparent); mask-image: linear-gradient(rgb(0 0 0 / 0.55), transparent);
 }
 
+.feeds { display: grid; min-height: 0; }
 .feed { list-style: none; margin: 0; padding: 20px 0 10px; overflow-y: auto; min-height: 0; }
+.feed[hidden] { display: none; }
 .msg { display: grid; grid-template-columns: 40px 1fr; gap: 0 14px; padding: 14px 28px; }
 @media (hover: hover) { .msg:hover { background: rgb(28 25 21 / 0.03); } }
 /* Consecutive messages from one author group under a single name, Slack style. */