Point the README's developer setup at the CTXD runbook

The Quick start procedure moves to CTXD (mealquest / RUNBOOKS.MD,
"Local development"), corrected there. It had also gone stale: it omitted
MEALQUEST_GOOGLE_CLIENT_ID and MEALQUEST_GOOGLE_CLIENT_SECRET_FILE, without
which the service refuses to start.

Task e81ed994-a510-48e6-9cf6-e76d5d81f56c.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -11,61 +11,14 @@ single Go service with the React PWA embedded in the binary.
 > `/health`, embedded PWA skeleton, Makefile, Dockerfile, CI). The planned
 > application is described in [docs/ARCHITECTURE.md](docs/ARCHITECTURE.md).
 
-## Quick start
+## Running it locally
 
-Requirements: Go 1.25 and Node.js `^22.22.2 || ^24.15.0 || >=26.0.0` — that
-is, 22.22.2 or later on the 22 line, 24.15.0 or later on the 24 line, or 26.0.0
-or later. Node.js 23, 24.0–24.14 and 25 are not supported: this is the
-`engines` range of jsdom in the committed lockfile, the strictest of all the
-web dependencies.
-
-```sh
-(cd web && npm ci)
-mkdir -p ~/.mealquest-dev   # outside the repository: it holds a secret
-chmod 700 ~/.mealquest-dev
-head -c 32 /dev/urandom | base64 > ~/.mealquest-dev/secret_key
-chmod 600 ~/.mealquest-dev/secret_key
-export MEALQUEST_HTTP_ADDR=:8080
-export MEALQUEST_PUBLIC_URL=http://localhost:5173
-export MEALQUEST_DATA_DIR="$HOME/.mealquest-dev"
-export MEALQUEST_SHUTDOWN_TIMEOUT=10s
-export MEALQUEST_SECRET_KEY_FILE="$HOME/.mealquest-dev/secret_key"
-# Authentik OAuth2/OpenID provider for MealQuest (redirect URI:
-# $MEALQUEST_PUBLIC_URL/auth/callback). Save its client secret to the file.
-export MEALQUEST_OIDC_ISSUER=https://auth.example.com/application/o/mealquest/
-export MEALQUEST_OIDC_CLIENT_ID=mealquest
-export MEALQUEST_OIDC_CLIENT_SECRET_FILE="$HOME/.mealquest-dev/oidc_client_secret"
-export MEALQUEST_OIDC_ALLOWED_GROUPS=mealquest-admin
-# Optional: sessions end after MEALQUEST_SESSION_IDLE unused (default 720h)
-# and always MEALQUEST_SESSION_MAX after sign-in (default 4320h).
-# export MEALQUEST_SESSION_IDLE=720h
-# export MEALQUEST_SESSION_MAX=4320h
-# Optional: comma-separated IPs/CIDRs of reverse proxies whose
-# X-Forwarded-For/-Proto headers are honoured (production: Traefik). Unset
-# trusts no peer, which is right for local development.
-# export MEALQUEST_TRUSTED_PROXY=10.60.1.33
-# Optional: a SearXNG instance the Settings screen suggests as the recipe
-# search URL until one is saved.
-# export MEALQUEST_SEARXNG_URL=http://localhost:8888
-export MEALQUEST_DEFAULT_TZ=America/New_York
-make dev
-```
-
-`make dev` runs the Go server on `:8080` and the Vite dev server on `:5173`
-(which proxies `/api`, `/auth` and `/media` to `:8080`). Open
-http://localhost:5173. Configuration is environment-only and fails fast:
-every variable above is required except the commented-out session
-lifetimes (when set they must be positive, with MAX at least IDLE),
-trusted proxy list (every entry must be an IP or CIDR), the SearXNG URL
-(an absolute `http://` or `https://` URL without credentials, a query or a
-fragment) and `MEALQUEST_DEFAULT_TZ`, and
-secrets are read only from files named by `*_FILE` variables. `MEALQUEST_PUBLIC_URL`, `MEALQUEST_OIDC_ISSUER` and the
-endpoints the issuer advertises must be `https://`; plain `http://` is
-accepted only for `localhost`, `127.0.0.1` and `[::1]`.
-`MEALQUEST_DEFAULT_TZ` is the IANA zone the household settings are created
-with on first boot: until those settings exist, boot fails unless it is a
-valid IANA zone. Later boots ignore it, set or not (change the zone in
-household settings instead).
+The developer setup (prerequisites, Authentik and Google clients, the
+`MEALQUEST_*` environment, `make dev` and the optional SearXNG sidecar) is
+runbook information and lives in CTXD: project `mealquest`, file
+`RUNBOOKS.MD`, section "Local development". Configuration is read only from
+the environment, and the service refuses to start, naming every missing or
+invalid variable.
 
 ## Common commands
 
@@ -78,7 +31,8 @@ household settings instead).
 
 ## Where to read next
 
-- [AGENTS.md](AGENTS.md) — house rules, approved dependencies, conventions.
+- [AGENTS.md](AGENTS.md) — house rules, approved dependencies, the quality
+  floor every change must pass, repository layout, conventions.
 - [docs/ARCHITECTURE.md](docs/ARCHITECTURE.md) — architecture of record.
 - [design/MealQuest Requirements.md](design/MealQuest%20Requirements.md) — product requirements.
 - [design/MealQuest UI Designs/design_handoff_mealquest/README.md](design/MealQuest%20UI%20Designs/design_handoff_mealquest/README.md) — UI handoff.

cmd/server/main.go

@@ -133,7 +133,7 @@ func run(cfg config.Config, logger *slog.Logger) error {
 		return err
 	}
 
-	shopSvc, err := shopping.NewService(db)
+	shopSvc, err := shopping.NewService(db, archiveTitler(ai, guard), runner, logger)
 	if err != nil {
 		return err
 	}
@@ -280,7 +280,7 @@ func newJobRunner(db *store.Store, logger *slog.Logger) (*jobs.Runner, *jobKinds
 // service registers its own kinds when it is built, before the runner
 // starts (dinners.NewService registers dinners.KindGroundDinner and
 // suggest.NewService suggest.KindSuggestionBatch, plan.NewService
-// plan.KindDraftWeek).
+// plan.KindDraftWeek, shopping.NewService shopping.KindTitleSupplyRun).
 func registerJobKinds(runner *jobs.Runner) (*jobKinds, error) {
 	builtins, err := jobs.RegisterBuiltins(runner)
 	if err != nil {
@@ -325,6 +325,18 @@ func weekDrafter(ai *aisettings.Service, guard *harness.Guard) plan.Drafter {
 	}
 }
 
+// archiveTitler runs archive_title with the AI settings current at each
+// run, sharing guard.
+func archiveTitler(ai *aisettings.Service, guard *harness.Guard) shopping.Titler {
+	return func(ctx context.Context, scope string, in skills.ArchiveTitleRequest) (skills.ArchiveTitle, error) {
+		cfg, err := ai.HarnessConfig(ctx, guard)
+		if err != nil {
+			return skills.ArchiveTitle{}, err
+		}
+		return skills.TitleArchive(ctx, cfg, scope, in)
+	}
+}
+
 // logListening logs the startup line. Only the public URL's origin is logged
 // so no credential-bearing URL component can reach the log.
 func logListening(logger *slog.Logger, cfg config.Config) {

deploy/.env.example

@@ -1,20 +1,15 @@
-# MealQuest production environment. Copy to deploy/.env (never committed)
-# and replace the placeholders. The service fails fast: a missing or invalid
-# required variable stops it at boot with the variable named.
+# MealQuest production environment: the template for deploy/.env (never
+# committed). The service fails fast: a missing or invalid required variable
+# stops it at boot with the variable named. Creating deploy/.env: CTXD
+# project mealquest, RUNBOOKS.MD "Stack and first deploy" > "3. Environment
+# file".
 #
 # Secrets are never set here. They live in deploy/secrets/ (never committed),
-# one value per file, owned by the container user and readable only by it:
-#
-#   mkdir -p deploy/secrets && chmod 700 deploy/secrets
-#   head -c 32 /dev/urandom | base64 > deploy/secrets/secret_key
-#   printf '%s\n' '<Authentik client secret>' > deploy/secrets/oidc_client_secret
-#   printf '%s\n' '<Google OAuth client secret>' > deploy/secrets/google_client_secret
-#   sudo chown 10001:10001 deploy/secrets/* && sudo chmod 600 deploy/secrets/*
-#
-# SearXNG's secret key is the exception: compose reads it itself, so it
-# stays owned by you (mode 0600). Create it after the chown above:
-#
-#   (umask 077; printf 'SEARXNG_SECRET=%s\n' "$(openssl rand -hex 32)" > deploy/secrets/searxng.env)
+# one value per file, owned by the container user 10001:10001 with mode
+# 0600: secret_key, oidc_client_secret and google_client_secret. SearXNG's
+# searxng.env is the exception: compose reads it itself, so it is owned by
+# the host account that runs compose, mode 0600. Creating them: CTXD project
+# mealquest, RUNBOOKS.MD "Stack and first deploy" > "4. Secrets".
 #
 # deploy/compose.yaml mounts them at /run/secrets/<name> and points the
 # *_FILE variables at them.
@@ -42,8 +37,7 @@ MEALQUEST_TRUSTED_PROXY=10.60.1.33
 
 # IANA zone the household settings are created with on first boot. Required
 # until those settings exist; ignored afterwards (change the zone in
-# household settings instead). Confirm the household's zone before the first
-# deploy.
+# household settings instead).
 MEALQUEST_DEFAULT_TZ=America/New_York
 
 # --- Authentik OIDC ----------------------------------------------------------
@@ -57,10 +51,10 @@ MEALQUEST_OIDC_ALLOWED_GROUPS=mealquest-admin
 
 # --- Google Calendar (Push to Calendar) ------------------------------------
 
-# Client ID of the Google OAuth web client (deploy/RUNBOOK.md "Google
-# Calendar OAuth client"). Required: the service will not start without it
-# and the client secret file. Its authorized redirect URI is
-# <MEALQUEST_PUBLIC_URL origin>/api/v1/integrations/google/callback.
+# Client ID of the Google OAuth web client (CTXD project mealquest,
+# RUNBOOKS.MD "Google Calendar OAuth client"). Required: the service will
+# not start without it and the client secret file. Its authorized redirect
+# URI is <MEALQUEST_PUBLIC_URL origin>/api/v1/integrations/google/callback.
 MEALQUEST_GOOGLE_CLIENT_ID=<client id>.apps.googleusercontent.com
 
 # Optional session lifetimes. A session ends after IDLE unused and always MAX
@@ -82,13 +76,14 @@ MEALQUEST_SESSION_MAX=4320h
 #   The SearXNG recipe-search sidecar on the compose network. The Settings
 #   screen pre-fills it as the SearXNG URL until one is saved; the saved
 #   provider and base URL come from PATCH /api/v1/settings/recipe-search.
-#   See deploy/RUNBOOK.md "Recipe search (SearXNG)".
+#   See CTXD project mealquest, RUNBOOKS.MD "Recipe search (SearXNG)".
 
 # --- Planned; not read by the service yet -------------------------------------
 #
 # Added to deploy/compose.yaml and this file by the features that use them.
 #
-# Web Push (Feature 19). Generate the key pair with cmd/vapidgen.
+# Web Push (Feature 19). Key pair: CTXD project mealquest, RUNBOOKS.MD
+# "VAPID keys (Web Push)".
 # MEALQUEST_VAPID_PUBLIC_KEY=<base64url VAPID public key>
 # MEALQUEST_VAPID_PRIVATE_KEY_FILE=/run/secrets/vapid_private_key
 # MEALQUEST_VAPID_SUBJECT=mailto:<owner address>

deploy/compose.dev.yaml

@@ -1,8 +1,7 @@
-# Development override: publishes SearXNG on the dev machine's loopback so
-# it can be queried directly, e.g.
-#
-#   docker compose -f deploy/compose.yaml -f deploy/compose.dev.yaml up -d searxng
-#   curl 'http://127.0.0.1:8888/search?q=chicken+tikka+masala+recipe&format=json'
+# Development override layered on deploy/compose.yaml: publishes SearXNG
+# on the dev machine's loopback (127.0.0.1:8888) so it can be queried
+# directly. Using it: CTXD project mealquest, RUNBOOKS.MD "Local
+# development".
 #
 # Loopback only, never a LAN address. Never used in production: the
 # systemd unit starts deploy/compose.yaml alone.

deploy/compose.yaml

@@ -1,18 +1,16 @@
-# Production stack for MealQuest on 10.60.1.14 (D-018). Build on the host,
-# then start through systemd:
-#
-#   docker compose -f deploy/compose.yaml build
-#   sudo systemctl restart mealquest
+# Production stack for MealQuest on 10.60.1.14 (D-018). Building, deploying
+# and operating it: CTXD project mealquest, RUNBOOKS.MD "Stack unit" and
+# "Routine deploy and rollback".
 #
 # The services use restart: "no" on purpose: Docker must not start them
 # before the DOCKER-USER firewall is applied. deploy/systemd/mealquest.service
 # owns start and stop and requires mealquest-firewall.service first.
 #
-# Configuration comes from deploy/.env (copy deploy/.env.example) and secrets
-# from deploy/secrets/; neither is committed. Compose bind-mounts file secrets
-# with their host owner and mode, so each file in deploy/secrets/ must be
-# owned by the container user 10001:10001 with mode 0600 (except
-# searxng.env, read by compose itself; see the searxng service).
+# Configuration comes from deploy/.env (template: deploy/.env.example) and
+# secrets from deploy/secrets/; neither is committed. Compose bind-mounts
+# file secrets with their host owner and mode, so each file in
+# deploy/secrets/ must be owned by the container user 10001:10001 with mode
+# 0600 (except searxng.env, read by compose itself; see the searxng service).
 name: mealquest
 
 services:
@@ -65,8 +63,8 @@ services:
   # the app's own user (owner of the volume) with a read-only root
   # filesystem, no privilege escalation and no Linux capabilities.
   #
-  # Restore: follow "Restore the database" in deploy/RUNBOOK.md (stop the
-  # stack, move the database with its -wal and -shm aside, restore, check).
+  # Restoring the database: CTXD project mealquest, RUNBOOKS.MD "Restore
+  # the database".
   litestream:
     image: litestream/litestream:0.5.17
     user: "10001:10001"

deploy/systemd/mealquest-firewall.service

@@ -5,8 +5,9 @@
 # are one-way: a failure here fails this unit visibly and never fails
 # docker.service.
 #
-# Start MealQuest only after this unit has succeeded:
-#   systemctl start mealquest-firewall && docker compose up -d
+# mealquest.service requires this unit and starts the stack only after it
+# has succeeded. Installing and operating both: CTXD project mealquest,
+# RUNBOOKS.MD "Host firewall" and "Stack unit".
 [Unit]
 Description=Restrict MealQuest port 8090 to Traefik (DOCKER-USER)
 After=docker.service

deploy/systemd/mealquest-media-backup.service

@@ -1,8 +1,7 @@
 # Runs the nightly MealQuest media backup (/usr/local/sbin/mealquest-media-backup).
-# Triggered by mealquest-media-backup.timer; run by hand with
-#   systemctl start mealquest-media-backup
-# and read the result with
-#   journalctl -u mealquest-media-backup
+# Triggered by mealquest-media-backup.timer; output goes to the journal.
+# Installing it and running it by hand: CTXD project mealquest,
+# RUNBOOKS.MD "Media — nightly rsync".
 #
 # The script runs as the app's user (10001, host user "mealquest") with no
 # capabilities. systemd, as root, only bind-mounts the data volume's root

deploy/systemd/mealquest-media-backup.sh

@@ -15,8 +15,9 @@
 # swapping the path afterwards cannot redirect it. Symlinks inside the
 # directory are copied as links (-a), never followed.
 #
-# The media directory is created at deploy time (deploy/RUNBOOK.md). If it
-# is missing the job fails; it is never treated as "nothing to back up".
+# The media directory is created at deploy time (CTXD project mealquest,
+# RUNBOOKS.MD "Media — nightly rsync"). If it is missing the job fails; it
+# is never treated as "nothing to back up".
 #
 # rsync mirrors into .../mealquest-backups/media/ only: the target ends in
 # a slash, so --delete removes files from that directory and nothing

docs/ARCHITECTURE.md

@@ -470,6 +470,45 @@ automatic** (D-021).
   not a Regular; and one whose reason is over 180 characters or names none
   of its cited Regulars. Cited names are rewritten as the household writes
   them. Grounding each survivor in a recipe is the caller's next step.
+- **Supply run titles** (`skills.TitleArchive`, skill `archive_title`
+  v1): from the names of the week's planned dinners in day order, writes
+  `{title}`, the Supply run's post title in the Supply archive, at the
+  household temperature with no household context. A title must be 1–48
+  characters on one line, with no emoji and no surrounding quotation
+  marks; a reply breaking a rule gets the one repair turn, never a
+  truncation. `shopping.Generate` (and `GeneratePushed`), on storing a
+  list that is still untitled — a new list, or one a failed title left
+  untitled — enqueues a `title_supply_run` job in the generation's
+  transaction and returns without waiting for it, so neither Push to
+  Calendar nor `POST /shopping/{weekStart}/generate` waits for a model
+  call; the list reads untitled until the job stores its title. The job's
+  scope is `<weekStart>@<plan revision>/<sha256 of the dinner names in
+  order>`, so runs share a title only for the same names (a renamed dinner
+  changes the names, not the revision). It writes `shopping_lists.title`
+  only while the list is untitled and not frozen. A title is written once;
+  a remake keeps it and enqueues no job. A failed title never fails the
+  generation: the list stays untitled (the UI shows the week label), the
+  failure is logged as a warning and recorded in `ai_runs`, the job fails
+  `title_failed`, and the week's next generation tries again.
+  `shopping.Freeze` titles a list still untitled once more before
+  freezing it (see Supply archive), through the same skill, scope and
+  conditional write.
+
+## Supply archive (Feature 17)
+
+`shopping.Freeze(weekStart)` moves a week's Supply run into the Supply
+archive: `status` becomes `archived` and `frozen_at` is set, after which
+generating the list or changing an item is 409 `archived`. It freezes only
+a week that has ended in the household's time zone (its Monday is before
+the Monday of the household's current week), so a week not yet ended is
+`ErrWeekNotEnded` and a week with no list `ErrListNotFound`; freezing a
+frozen list does nothing. A list still untitled is titled first with
+`archive_title` from the week's plan, as `Generate` titles it; a title
+that cannot be written is logged and the list is frozen untitled, when its
+week label stands in for good. A `title_supply_run` job still in flight
+with the same scope shares that run (`harness.Run`); whichever stores the
+title first wins, and a job storing after the freeze stores nothing. The
+`week_rollover` schedule is to call `Freeze` for last week.
 
 ## Recipe grounding
 
@@ -770,6 +809,20 @@ Runs are recorded in `schedule_runs` and executed through `jobs`.
   needed, needed_count, total_count}` with the list's counts after the
   change. 404 for an unknown item, 409 `archived` when the list is in the
   Supply archive, 400 `invalid_request` for a bad body.
+- `GET /api/v1/shopping/archive?by=week|month|year` returns the Supply
+  archive `{by, periods: [{key, heading, posts: [{weekStart, label,
+  title, dinnerCount, itemCount, onHandCount, dinners, current}]}]}`: the
+  Supply run of every week up to the household's current week, newest
+  first, grouped by the Monday's ISO week (`key` "2026-W41", `heading` the
+  week label), month ("2026-10", "October 2026") or year ("2026"). The
+  Monday is a household-local date, so the week of Monday 28 December
+  is in December. `label` is the week label ("Week 41 · Oct 5 – 11"; the
+  UI sets it in capitals), `title` null while untitled, `dinners` the
+  list's dinners in day order and `dinnerCount` their number,
+  `itemCount` all items, `onHandCount` the items marked "have it", and
+  `current` true for the household's current week. 400 `invalid_request`
+  for any other `by`. A frozen list is read through `GET
+  /api/v1/shopping/{weekStart}` with `status` `archived`.
 
 ## Frontend
 

internal/ai/skills/archive_title.go

@@ -0,0 +1,148 @@
+package skills
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+	"unicode/utf8"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/llm"
+)
+
+// TitleLimit is the most characters a Supply run's title may have.
+const TitleLimit = 48
+
+// ArchiveTitleRequest is what archive_title reads.
+type ArchiveTitleRequest struct {
+	// Dinners are the names of the week's planned dinners in day order,
+	// Monday first. It must hold at least one, none blank.
+	Dinners []string
+}
+
+// ArchiveTitle is archive_title's output.
+type ArchiveTitle struct {
+	// Title is the Supply run's post title in the Supply archive: 1 to
+	// TitleLimit characters on one line, with no emoji and no surrounding
+	// quotation marks.
+	Title string `json:"title"`
+}
+
+// TitleArchive runs archive_title v1 on in and returns the title of the
+// week's Supply run, written from its dinners. A request with no dinners,
+// or a blank one, fails before any LLM call. scope names the week and its
+// dinners (see harness.Run).
+func TitleArchive(ctx context.Context, cfg harness.Config, scope string, in ArchiveTitleRequest) (ArchiveTitle, error) {
+	return harness.Run(ctx, cfg, archiveTitle{}, scope, in)
+}
+
+// archiveTitle is the skill.
+type archiveTitle struct{}
+
+var _ harness.Skill[ArchiveTitleRequest, ArchiveTitle] = archiveTitle{}
+
+func (archiveTitle) Name() string { return "archive_title" }
+
+func (archiveTitle) Version() int { return 1 }
+
+func (archiveTitle) Timeout() time.Duration { return harness.DefaultTimeout }
+
+// archiveTitlePrompt is the template data of archive_title.v1.tmpl.
+type archiveTitlePrompt struct {
+	// Dinners are the week's dinner names in day order, each on one line.
+	Dinners []string
+}
+
+func (archiveTitle) PromptInput(in ArchiveTitleRequest) (harness.PromptInput, error) {
+	if len(in.Dinners) == 0 {
+		return harness.PromptInput{}, errors.New("the week has no dinners to title it from")
+	}
+	var p archiveTitlePrompt
+	for i, name := range in.Dinners {
+		name = oneLine(name)
+		if name == "" {
+			return harness.PromptInput{}, fmt.Errorf("dinner %d has a blank name", i+1)
+		}
+		p.Dinners = append(p.Dinners, name)
+	}
+	return harness.PromptInput{Data: p}, nil
+}
+
+func (archiveTitle) Schema() llm.JSONSchema {
+	return llm.JSONSchema{Name: "archive_title", Schema: json.RawMessage(`{
+		"type": "object",
+		"properties": {
+			"title": {"type": "string"}
+		},
+		"required": ["title"],
+		"additionalProperties": false
+	}`)}
+}
+
+// UnmarshalJSON decodes the output, requiring its field as the schema
+// does.
+func (t *ArchiveTitle) UnmarshalJSON(data []byte) error {
+	if err := requireFields(data, nil, "title"); err != nil {
+		return fmt.Errorf("output %s", err)
+	}
+	type plain ArchiveTitle
+	return json.Unmarshal(data, (*plain)(t))
+}
+
+// quotes are the quotation marks a title may not start or end with.
+const quotes = `"'` + "`" + "“”‘’„‚«»‹›「」『』"
+
+// Validate finds every broken rule of the title as PostProcess will store
+// it, on one line: empty, over TitleLimit characters, holding an emoji, or
+// starting or ending with a quotation mark.
+func (archiveTitle) Validate(out ArchiveTitle) []string {
+	var problems []string
+	title := oneLine(out.Title)
+	switch n := utf8.RuneCountInString(title); {
+	case n == 0:
+		problems = append(problems, fmt.Sprintf("title is empty; give a title of 1 to %d characters", TitleLimit))
+	case n > TitleLimit:
+		problems = append(problems, fmt.Sprintf("title %q has %d characters; shorten it to at most %d", title, n, TitleLimit))
+	}
+	for _, r := range title {
+		if isEmoji(r) {
+			problems = append(problems, fmt.Sprintf("title %q has an emoji (%U); use words only", title, r))
+			break
+		}
+	}
+	if first, _ := utf8.DecodeRuneInString(title); title != "" && strings.ContainsRune(quotes, first) {
+		problems = append(problems, fmt.Sprintf("title %q starts with a quotation mark; give the title without quotation marks around it", title))
+	} else if last, _ := utf8.DecodeLastRuneInString(title); title != "" && strings.ContainsRune(quotes, last) {
+		problems = append(problems, fmt.Sprintf("title %q ends with a quotation mark; give the title without quotation marks around it", title))
+	}
+	return problems
+}
+
+// isEmoji reports whether r is an emoji or a part of one: a pictograph,
+// a symbol from the emoji blocks, a regional indicator, a keycap, a skin
+// tone, an emoji variation selector or the zero-width joiner.
+func isEmoji(r rune) bool {
+	switch {
+	case r >= 0x1F000 && r <= 0x1FAFF: // tiles, cards, enclosed, pictographs, emoticons, transport, supplemental symbols
+		return true
+	case r >= 0x2600 && r <= 0x27BF: // miscellaneous symbols and dingbats
+		return true
+	case r >= 0x2B00 && r <= 0x2BFF: // arrows and stars such as ⭐ and ⬛
+		return true
+	case r >= 0x2300 && r <= 0x23FF: // technical symbols such as ⌚ and ⏰
+		return true
+	case r >= 0xE0020 && r <= 0xE007F: // tag sequences of flags
+		return true
+	case r == 0x200D, r == 0x20E3, r == 0xFE0F: // joiner, keycap, emoji presentation
+		return true
+	}
+	return false
+}
+
+// PostProcess puts the title on one line, collapsing its white space.
+func (archiveTitle) PostProcess(out ArchiveTitle) (ArchiveTitle, error) {
+	return ArchiveTitle{Title: oneLine(out.Title)}, nil
+}

internal/ai/skills/archive_title_test.go

@@ -0,0 +1,170 @@
+package skills
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"slices"
+	"strings"
+	"testing"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/llm"
+)
+
+// titleWeek is a week of seven dinners, Monday first.
+var titleWeek = ArchiveTitleRequest{Dinners: []string{
+	"Beef Chili", "Pot Roast", "Chicken  Fajitas", "Spaghetti Bolognese", "Sheet Pan Salmon", "Pad Thai", "Fish Tacos",
+}}
+
+func titleReply(title string) llm.GenerateResult {
+	return reply(fmt.Sprintf(`{"title":%q}`, title))
+}
+
+// title runs TitleArchive on in with f and checks f was called exactly
+// calls times, each at the household temperature with the archive_title
+// schema.
+func title(t *testing.T, f *llm.Fake, in ArchiveTitleRequest, calls int) (ArchiveTitle, []llm.Request, error) {
+	t.Helper()
+	out, err := TitleArchive(context.Background(), testConfig(t, f), "2026-10-12", in)
+	reqs := f.Requests()
+	if len(reqs) != calls {
+		t.Fatalf("Generate called %d times, want %d", len(reqs), calls)
+	}
+	if g, _, _ := f.Remaining(); g != 0 {
+		t.Fatalf("%d scripted Generate results unused", g)
+	}
+	for i, req := range reqs {
+		if req.Temperature == nil || *req.Temperature != 0.7 {
+			t.Fatalf("request %d temperature = %v, want 0.7", i+1, req.Temperature)
+		}
+		if req.Schema == nil || req.Schema.Name != "archive_title" {
+			t.Fatalf("request %d schema = %v, want archive_title", i+1, req.Schema)
+		}
+	}
+	return out, reqs, err
+}
+
+func TestArchiveTitleValid(t *testing.T) {
+	var f llm.Fake
+	f.QueueGenerate(titleReply("  Slow Simmers\nand Taco Night "))
+	out, reqs, err := title(t, &f, titleWeek, 1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if out.Title != "Slow Simmers and Taco Night" {
+		t.Fatalf("title = %q", out.Title)
+	}
+	system, user := reqs[0].System, reqs[0].Messages[0].Content
+	golden(t, "archive_title_valid.system.golden", system)
+	golden(t, "archive_title_valid.user.golden", user)
+	want := "Title the week whose dinners are, in day order from Monday:\n" +
+		"- Beef Chili\n- Pot Roast\n- Chicken Fajitas\n- Spaghetti Bolognese\n- Sheet Pan Salmon\n- Pad Thai\n- Fish Tacos"
+	if user != want {
+		t.Errorf("user message = %q, want %q", user, want)
+	}
+	if !strings.Contains(system, "## Output contract") || !strings.Contains(system, `"title"`) {
+		t.Error("system prompt lacks the output contract")
+	}
+}
+
+// titleRepaired checks a first reply is repaired once, quoting it and the
+// problem wanted.
+func titleRepaired(t *testing.T, first, want string) {
+	t.Helper()
+	var f llm.Fake
+	f.QueueGenerate(titleReply(first), titleReply("Chili, Roast and Taco Night"))
+	out, reqs, err := title(t, &f, titleWeek, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if out.Title != "Chili, Roast and Taco Night" {
+		t.Fatalf("title = %q", out.Title)
+	}
+	repair := reqs[1].Messages
+	if len(repair) != 3 || repair[1].Content != fmt.Sprintf(`{"title":%q}`, first) {
+		t.Fatalf("repair turn does not quote the first reply: %+v", repair)
+	}
+	if !strings.Contains(repair[2].Content, want) {
+		t.Fatalf("repair message = %q, want it to contain %q", repair[2].Content, want)
+	}
+}
+
+func TestArchiveTitleTooLongRepaired(t *testing.T) {
+	long := "A Week of Slow Simmers, Sizzling Fajitas and Taco Night" // 55 characters
+	titleRepaired(t, long, fmt.Sprintf("title %q has 55 characters; shorten it to at most 48", long))
+}
+
+func TestArchiveTitleEmojiRepaired(t *testing.T) {
+	titleRepaired(t, "Taco Night 🌮", `title "Taco Night 🌮" has an emoji (U+1F32E); use words only`)
+}
+
+func TestArchiveTitleQuotedRepaired(t *testing.T) {
+	titleRepaired(t, `"Taco Night"`, `title "\"Taco Night\"" starts with a quotation mark; give the title without quotation marks around it`)
+}
+
+func TestArchiveTitleEmojiTwiceFails(t *testing.T) {
+	var f llm.Fake
+	f.QueueGenerate(titleReply("Chili Week 🔥"), titleReply("Chili Week ❤️"))
+	out, _, err := title(t, &f, titleWeek, 2)
+	var bad *harness.BadOutputError
+	if !errors.As(err, &bad) || !errors.Is(err, llm.ErrBadOutput) {
+		t.Fatalf("err = %v, want a BadOutputError", err)
+	}
+	if !slices.Equal(bad.Repair, []string{`title "Chili Week ❤️" has an emoji (U+2764); use words only`}) {
+		t.Fatalf("repair problems = %q", bad.Repair)
+	}
+	if out.Title != "" {
+		t.Fatalf("title = %q, want none", out.Title)
+	}
+}
+
+func TestArchiveTitleRules(t *testing.T) {
+	s := archiveTitle{}
+	for _, tc := range []struct {
+		title string
+		want  []string
+	}{
+		{"Taco Night", nil},
+		{strings.Repeat("a", TitleLimit), nil},
+		{"Crème Brûlée & Co.", nil},
+		{"Fajitas — Then Tacos", nil},
+		{"Mom's Pot Roast Week", nil},
+		{"  Spaced   out  ", nil},
+		{"", []string{"title is empty; give a title of 1 to 48 characters"}},
+		{" \n ", []string{"title is empty; give a title of 1 to 48 characters"}},
+		{strings.Repeat("é", TitleLimit+1), []string{fmt.Sprintf("title %q has 49 characters; shorten it to at most 48", strings.Repeat("é", TitleLimit+1))}},
+		{"Hot ☕ Week", []string{`title "Hot ☕ Week" has an emoji (U+2615); use words only`}},
+		{"Star ⭐ Week", []string{`title "Star ⭐ Week" has an emoji (U+2B50); use words only`}},
+		{"Go 🇮🇹", []string{`title "Go 🇮🇹" has an emoji (U+1F1EE); use words only`}},
+		{"‘Taco Night’", []string{`title "‘Taco Night’" starts with a quotation mark; give the title without quotation marks around it`}},
+		{"Taco Night”", []string{`title "Taco Night”" ends with a quotation mark; give the title without quotation marks around it`}},
+		{"«Pasta» 🍝 " + strings.Repeat("x", 45), []string{
+			fmt.Sprintf("title %q has 55 characters; shorten it to at most 48", "«Pasta» 🍝 "+strings.Repeat("x", 45)),
+			fmt.Sprintf("title %q has an emoji (U+1F35D); use words only", "«Pasta» 🍝 "+strings.Repeat("x", 45)),
+			fmt.Sprintf("title %q starts with a quotation mark; give the title without quotation marks around it", "«Pasta» 🍝 "+strings.Repeat("x", 45)),
+		}},
+	} {
+		if got := s.Validate(ArchiveTitle{Title: tc.title}); !slices.Equal(got, tc.want) {
+			t.Errorf("Validate(%q) =\n%q\nwant\n%q", tc.title, got, tc.want)
+		}
+	}
+}
+
+func TestArchiveTitleBadRequestFailsBeforeCall(t *testing.T) {
+	for name, tc := range map[string]struct {
+		in   ArchiveTitleRequest
+		want string
+	}{
+		"no dinners":   {ArchiveTitleRequest{}, "the week has no dinners to title it from"},
+		"blank dinner": {ArchiveTitleRequest{Dinners: []string{"Pad Thai", " \n"}}, "dinner 2 has a blank name"},
+	} {
+		t.Run(name, func(t *testing.T) {
+			var f llm.Fake
+			_, _, err := title(t, &f, tc.in, 0)
+			if err == nil || !strings.Contains(err.Error(), tc.want) {
+				t.Fatalf("err = %v, want one containing %q", err, tc.want)
+			}
+		})
+	}
+}

internal/ai/skills/prompts/archive_title.v1.tmpl

@@ -0,0 +1,22 @@
+{{/* archive_title titles a week's Supply run for the Supply archive, from the week's dinners. */}}
+{{define "instructions" -}}
+You title the household's Supply run, the week's shopping list, as it is filed in the Supply archive: a blog-style history of the household's weeks of dinners. Write one short, warm, playful post title for the week, drawn from its dinners.
+
+Rules:
+- At most 48 characters, on one line.
+- Words only: no emoji.
+- No quotation marks around the title.
+- Do not name a date or week number; the archive shows those.
+
+Give:
+- title: the title.
+
+One valid reply, for a week of Beef Chili, Pot Roast and Fish Tacos (an example only, not about this household):
+{"title": "Slow Simmers and Taco Night"}
+{{- end}}
+{{define "user" -}}
+Title the week whose dinners are, in day order from Monday:
+{{- range .Dinners}}
+- {{.}}
+{{- end}}
+{{- end}}

internal/ai/skills/prompts/checksums.txt

@@ -5,3 +5,4 @@ echo v1 ab5d7884f5c7a2261c06b0c9353bb9597070c001420bd4cbb6ec6272c093fdce
 normalize_recipe v1 7174e5479fc020f3b2b39953d85411381aea26defb9943145e7864c5b752d7ee
 suggest_side_quests v1 bd54d7bf9aea0980059a346e5f40ff4c866b80ef9bb9f74e7cbd413be0911c8a
 draft_week v1 e637419690d9532bab53cb8ca01b73a079ecfe8e3022522c05188d18e9740f32
+archive_title v1 b4f30562a8614dac09a69d512dc361883b917ee4228a0ce3b4583c7fd3f6101a

internal/ai/skills/testdata/archive_title_valid.system.golden

@@ -0,0 +1,33 @@
+## Instructions
+You title the household's Supply run, the week's shopping list, as it is filed in the Supply archive: a blog-style history of the household's weeks of dinners. Write one short, warm, playful post title for the week, drawn from its dinners.
+
+Rules:
+- At most 48 characters, on one line.
+- Words only: no emoji.
+- No quotation marks around the title.
+- Do not name a date or week number; the archive shows those.
+
+Give:
+- title: the title.
+
+One valid reply, for a week of Beef Chili, Pot Roast and Fish Tacos (an example only, not about this household):
+{"title": "Slow Simmers and Taco Night"}
+
+## Household context
+No household context.
+
+## Output contract
+This contract overrides any earlier instruction about the form of your reply. Reply with one JSON value matching the JSON Schema "archive_title" below, and nothing else: no prose and no Markdown code fences.
+
+{
+  "type": "object",
+  "properties": {
+    "title": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "title"
+  ],
+  "additionalProperties": false
+}

internal/ai/skills/testdata/archive_title_valid.user.golden

@@ -0,0 +1,8 @@
+Title the week whose dinners are, in day order from Monday:
+- Beef Chili
+- Pot Roast
+- Chicken Fajitas
+- Spaghetti Bolognese
+- Sheet Pan Salmon
+- Pad Thai
+- Fish Tacos

internal/db/querier.go

@@ -87,6 +87,9 @@ type Querier interface {
 	// Records a pending or running batch as done or failed; a batch already
 	// finished is left as it is (0 rows).
 	FinishSuggestionBatch(ctx context.Context, arg FinishSuggestionBatchParams) (int64, error)
+	// Freezes list id into the Supply archive at frozen_at, unless it is
+	// frozen already.
+	FreezeShoppingList(ctx context.Context, arg FreezeShoppingListParams) (int64, error)
 	// Returns sql.ErrNoRows until the row exists.
 	GetAISettings(ctx context.Context) (AiSetting, error)
 	// The job of kind queued or running for the week starting week_start,
@@ -184,6 +187,9 @@ type Querier interface {
 	// The items of list list_id with their group's dinner, in list order: by
 	// group, then by item.
 	ListShoppingItems(ctx context.Context, listID string) ([]ListShoppingItemsRow, error)
+	// The Supply runs of the weeks starting on or before week_start, newest
+	// week first.
+	ListShoppingListsThrough(ctx context.Context, weekStart string) ([]ShoppingList, error)
 	// The ids of the dinners with status quest_log planned on date, on a plan
 	// of any status, that have no Rotation check for date yet.
 	ListTriedCandidates(ctx context.Context, date string) ([]string, error)
@@ -243,6 +249,9 @@ type Querier interface {
 	SetPlanDayCalendarEvent(ctx context.Context, arg SetPlanDayCalendarEventParams) (int64, error)
 	// Marks item id needed (1) or "have it" (0).
 	SetShoppingItemNeeded(ctx context.Context, arg SetShoppingItemNeededParams) error
+	// Titles list id, unless it has a title already or is frozen into the
+	// Supply archive.
+	SetShoppingListTitle(ctx context.Context, arg SetShoppingListTitleParams) (int64, error)
 	// Marks a pending batch running; a batch in any other status is left as
 	// it is (0 rows).
 	StartSuggestionBatch(ctx context.Context, arg StartSuggestionBatchParams) (int64, error)

internal/db/shopping.sql.go

@@ -112,6 +112,28 @@ func (q *Queries) DeleteShoppingItem(ctx context.Context, id string) error {
 	return err
 }
 
+const freezeShoppingList = `-- name: FreezeShoppingList :execrows
+UPDATE shopping_lists
+SET status = 'archived', frozen_at = ?, updated_at = ?
+WHERE id = ? AND frozen_at IS NULL
+`
+
+type FreezeShoppingListParams struct {
+	FrozenAt  sql.NullString
+	UpdatedAt string
+	ID        string
+}
+
+// Freezes list id into the Supply archive at frozen_at, unless it is
+// frozen already.
+func (q *Queries) FreezeShoppingList(ctx context.Context, arg FreezeShoppingListParams) (int64, error) {
+	result, err := q.db.ExecContext(ctx, freezeShoppingList, arg.FrozenAt, arg.UpdatedAt, arg.ID)
+	if err != nil {
+		return 0, err
+	}
+	return result.RowsAffected()
+}
+
 const getShoppingItemList = `-- name: GetShoppingItemList :one
 SELECT shopping_lists.id, shopping_lists.week_start, shopping_lists.plan_id, shopping_lists.title, shopping_lists.status, shopping_lists.sent_to_chat_at, shopping_lists.frozen_at, shopping_lists.created_at, shopping_lists.updated_at
 FROM shopping_items
@@ -299,6 +321,47 @@ func (q *Queries) ListShoppingItems(ctx context.Context, listID string) ([]ListS
 	return items, nil
 }
 
+const listShoppingListsThrough = `-- name: ListShoppingListsThrough :many
+SELECT id, week_start, plan_id, title, status, sent_to_chat_at, frozen_at, created_at, updated_at FROM shopping_lists
+WHERE week_start <= ?
+ORDER BY week_start DESC
+`
+
+// The Supply runs of the weeks starting on or before week_start, newest
+// week first.
+func (q *Queries) ListShoppingListsThrough(ctx context.Context, weekStart string) ([]ShoppingList, error) {
+	rows, err := q.db.QueryContext(ctx, listShoppingListsThrough, weekStart)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var items []ShoppingList
+	for rows.Next() {
+		var i ShoppingList
+		if err := rows.Scan(
+			&i.ID,
+			&i.WeekStart,
+			&i.PlanID,
+			&i.Title,
+			&i.Status,
+			&i.SentToChatAt,
+			&i.FrozenAt,
+			&i.CreatedAt,
+			&i.UpdatedAt,
+		); err != nil {
+			return nil, err
+		}
+		items = append(items, i)
+	}
+	if err := rows.Close(); err != nil {
+		return nil, err
+	}
+	if err := rows.Err(); err != nil {
+		return nil, err
+	}
+	return items, nil
+}
+
 const moveShoppingGroup = `-- name: MoveShoppingGroup :exec
 UPDATE shopping_groups
 SET position = ?, updated_at = ?
@@ -378,3 +441,25 @@ func (q *Queries) SetShoppingItemNeeded(ctx context.Context, arg SetShoppingItem
 	_, err := q.db.ExecContext(ctx, setShoppingItemNeeded, arg.Needed, arg.UpdatedAt, arg.ID)
 	return err
 }
+
+const setShoppingListTitle = `-- name: SetShoppingListTitle :execrows
+UPDATE shopping_lists
+SET title = ?, updated_at = ?
+WHERE id = ? AND title IS NULL AND status = 'current' AND frozen_at IS NULL
+`
+
+type SetShoppingListTitleParams struct {
+	Title     sql.NullString
+	UpdatedAt string
+	ID        string
+}
+
+// Titles list id, unless it has a title already or is frozen into the
+// Supply archive.
+func (q *Queries) SetShoppingListTitle(ctx context.Context, arg SetShoppingListTitleParams) (int64, error) {
+	result, err := q.db.ExecContext(ctx, setShoppingListTitle, arg.Title, arg.UpdatedAt, arg.ID)
+	if err != nil {
+		return 0, err
+	}
+	return result.RowsAffected()
+}

internal/server/plans_test.go

@@ -37,6 +37,8 @@ type plansEnv struct {
 	h        http.Handler
 	st       *store.Store
 	svc      *plan.Service
+	shop     *shopping.Service
+	runner   *jobs.Runner
 	questLog string
 	// google is the fake Google the plan service pushes to; it starts
 	// unconnected.
@@ -47,6 +49,13 @@ type plansEnv struct {
 }
 
 func newPlansRouter(t *testing.T) plansEnv {
+	t.Helper()
+	return newPlansRouterTitled(t, untitled)
+}
+
+// newPlansRouterTitled is newPlansRouter whose Supply runs are titled by
+// title.
+func newPlansRouterTitled(t *testing.T, title shopping.Titler) plansEnv {
 	t.Helper()
 	st := newTestStore(t)
 	ctx := t.Context()
@@ -80,7 +89,7 @@ func newPlansRouter(t *testing.T) plansEnv {
 	if err != nil {
 		t.Fatal(err)
 	}
-	shop, err := shopping.NewService(st)
+	shop, err := shopping.NewService(st, title, runner, logger)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -119,7 +128,7 @@ func newPlansRouter(t *testing.T) plansEnv {
 			t.Fatal(err)
 		}
 	}
-	return plansEnv{h: h, st: st, svc: svc, questLog: dinner("Pad Thai", "quest_log", "stovetop", 35),
+	return plansEnv{h: h, st: st, svc: svc, shop: shop, runner: runner, questLog: dinner("Pad Thai", "quest_log", "stovetop", 35),
 		google: google, gcal: googleSvc, logs: logs}
 }
 

internal/server/server.go

@@ -49,7 +49,8 @@ type RouteMounter interface {
 // /api/v1/plans/{weekStart}/days/{date}, GET /api/v1/rotation-reviews and
 // POST /api/v1/dinners/{id}/rotation-review, and POST
 // /api/v1/plans/{weekStart}/push-calendar with shopSvc, which makes the
-// pushed week's Supply run; shopSvc serves GET /api/v1/shopping/{weekStart},
+// pushed week's Supply run; shopSvc serves GET /api/v1/shopping/archive,
+// GET /api/v1/shopping/{weekStart},
 // POST /api/v1/shopping/{weekStart}/generate and PATCH
 // /api/v1/shopping/items/{id}; googleSvc serves GET
 // /api/v1/integrations/google and its /connect, /callback and /calendars,
@@ -142,6 +143,7 @@ func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, a
 	apiV1.Post("/plans/{weekStart}/draft", postPlanDraft(logger, planSvc))
 	apiV1.Put("/plans/{weekStart}/days/{date}", putPlanDay(logger, planSvc))
 	apiV1.Post("/plans/{weekStart}/push-calendar", postPlanPush(logger, planSvc, shopSvc))
+	apiV1.Get("/shopping/archive", getSupplyArchive(logger, shopSvc))
 	apiV1.Get("/shopping/{weekStart}", getSupplyRun(logger, shopSvc))
 	apiV1.Post("/shopping/{weekStart}/generate", postSupplyRunGenerate(logger, shopSvc))
 	apiV1.Patch("/shopping/items/{id}", patchShoppingItem(logger, shopSvc))

internal/server/server_test.go

@@ -211,16 +211,28 @@ func newTestPlan(t *testing.T) *plan.Service {
 }
 
 // newTestShopping returns a shopping service over a migrated temp
-// database.
+// database, whose Supply runs stay untitled.
 func newTestShopping(t *testing.T) *shopping.Service {
 	t.Helper()
-	svc, err := shopping.NewService(newTestStore(t))
+	st := newTestStore(t)
+	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
+	runner, err := jobs.NewRunner(st, logger, 1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	svc, err := shopping.NewService(st, untitled, runner, logger)
 	if err != nil {
 		t.Fatal(err)
 	}
 	return svc
 }
 
+// untitled is a shopping.Titler with no model: every Supply run it is
+// asked to title stays untitled.
+func untitled(context.Context, string, skills.ArchiveTitleRequest) (skills.ArchiveTitle, error) {
+	return skills.ArchiveTitle{}, errors.New("no model in this test")
+}
+
 // newTestBox returns a secret box under a random key.
 func newTestBox(t *testing.T) *secretbox.Box {
 	t.Helper()

internal/server/shopping.go

@@ -143,6 +143,70 @@ func patchShoppingItem(logger *slog.Logger, svc *shopping.Service) http.HandlerF
 	}
 }
 
+// supplyArchive is the GET /shopping/archive answer: the Supply archive's
+// periods, newest first, as grouped by by.
+type supplyArchive struct {
+	By      string          `json:"by"`
+	Periods []archivePeriod `json:"periods"`
+}
+
+// archivePeriod is one heading of the Supply archive and its posts,
+// newest first.
+type archivePeriod struct {
+	Key     string        `json:"key"`
+	Heading string        `json:"heading"`
+	Posts   []archivePost `json:"posts"`
+}
+
+// archivePost is one week's Supply run in the Supply archive. label is
+// the week label, which stands in for title while it is null, and
+// onHandCount counts the items marked "have it".
+type archivePost struct {
+	WeekStart   string   `json:"weekStart"`
+	Label       string   `json:"label"`
+	Title       *string  `json:"title"`
+	DinnerCount int      `json:"dinnerCount"`
+	ItemCount   int      `json:"itemCount"`
+	OnHandCount int      `json:"onHandCount"`
+	Dinners     []string `json:"dinners"`
+	Current     bool     `json:"current"`
+}
+
+// getSupplyArchive answers GET /shopping/archive?by=week|month|year with
+// the Supply archive grouped by that period.
+func getSupplyArchive(logger *slog.Logger, svc *shopping.Service) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		by := r.URL.Query().Get("by")
+		periods, err := svc.Archive(r.Context(), by)
+		if errors.Is(err, shopping.ErrInvalidPeriod) {
+			writeError(w, r, logger, http.StatusBadRequest, "invalid_request", shopping.ErrInvalidPeriod.Error())
+			return
+		}
+		if err != nil {
+			writeShoppingError(w, r, logger, "read Supply archive", err)
+			return
+		}
+		out := supplyArchive{By: by, Periods: make([]archivePeriod, len(periods))}
+		for i, p := range periods {
+			posts := make([]archivePost, len(p.Posts))
+			for j, post := range p.Posts {
+				posts[j] = archivePost{
+					WeekStart:   post.WeekStart,
+					Label:       post.Label,
+					Title:       post.Title,
+					DinnerCount: len(post.Dinners),
+					ItemCount:   post.Items,
+					OnHandCount: post.OnHand,
+					Dinners:     post.Dinners,
+					Current:     post.Current,
+				}
+			}
+			out.Periods[i] = archivePeriod{Key: p.Key, Heading: p.Heading, Posts: posts}
+		}
+		writeJSON(w, r, logger, http.StatusOK, out)
+	}
+}
+
 // supplyRunOf is l, the Supply run of the week starting week, as the API
 // shows it.
 func supplyRunOf(week store.LocalDate, l shopping.List) (supplyRun, error) {

internal/server/shopping_test.go

@@ -1,16 +1,24 @@
 package server
 
 import (
+	"context"
 	"database/sql"
 	"encoding/json"
+	"errors"
+	"fmt"
 	"net/http"
 	"reflect"
 	"slices"
 	"strings"
 	"testing"
+	"time"
 
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/skills"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/plan"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/shopping"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
 )
 
@@ -378,6 +386,128 @@ func TestPushPlanMakesSupplyRun(t *testing.T) {
 	}
 }
 
+// heldTitler is a shopping.Titler that reports each call on entered and
+// answers title only once release is closed.
+type heldTitler struct {
+	entered chan struct{}
+	release chan struct{}
+}
+
+func newHeldTitler() heldTitler {
+	return heldTitler{entered: make(chan struct{}, 4), release: make(chan struct{})}
+}
+
+func (h heldTitler) title(ctx context.Context, _ string, _ skills.ArchiveTitleRequest) (skills.ArchiveTitle, error) {
+	h.entered <- struct{}{}
+	select {
+	case <-h.release:
+		return skills.ArchiveTitle{Title: "Chili and Friends"}, nil
+	case <-ctx.Done():
+		return skills.ArchiveTitle{}, ctx.Err()
+	}
+}
+
+// startRunner starts e's job runner, stopping it when the test ends. e's
+// logs must not be read while it runs.
+func (e plansEnv) startRunner(t *testing.T) {
+	t.Helper()
+	ctx, cancel := context.WithCancel(context.Background())
+	if err := e.runner.Start(ctx); err != nil {
+		cancel()
+		t.Fatal(err)
+	}
+	t.Cleanup(func() {
+		cancel()
+		e.runner.Wait()
+	})
+}
+
+// waitEntered waits for the title call to begin.
+func (h heldTitler) waitEntered(t *testing.T) {
+	t.Helper()
+	select {
+	case <-h.entered:
+	case <-time.After(10 * time.Second):
+		t.Fatal("archive_title was never called")
+	}
+}
+
+// waitTitled waits for the week's Supply run to have a title through GET
+// and returns it.
+func (e plansEnv) waitTitled(t *testing.T) string {
+	t.Helper()
+	deadline := time.Now().Add(10 * time.Second)
+	for {
+		var l supplyRunJSON
+		callShopping(t, e, http.MethodGet, shoppingPath+"2026-10-12", "", &l)
+		if l.Title != nil {
+			return *l.Title
+		}
+		if time.Now().After(deadline) {
+			t.Fatal("the Supply run was never titled")
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+}
+
+// TestPushPlanDoesNotWaitForTitle: Push to Calendar answers while the
+// Supply run's title is still being written; the list reads untitled until
+// the title job stores it.
+func TestPushPlanDoesNotWaitForTitle(t *testing.T) {
+	t.Parallel()
+	held := newHeldTitler()
+	e := newPlansRouterTitled(t, held.title)
+	e.groundWeek(t)
+	e.connectCalendar(t, true)
+	e.startRunner(t)
+
+	rec, body := callDinners(t, e.h, http.MethodPost, plansPath+"2026-10-12/push-calendar", "")
+	if rec.Code != http.StatusOK || body["status"] != "synced" {
+		t.Fatalf("push = %d %s", rec.Code, rec.Body)
+	}
+	if want := map[string]any{"status": "generated", "error": nil}; !reflect.DeepEqual(body["supply_run"], want) {
+		t.Errorf("supply_run = %v, want %v", body["supply_run"], want)
+	}
+	held.waitEntered(t)
+	var l supplyRunJSON
+	callShopping(t, e, http.MethodGet, shoppingPath+"2026-10-12", "", &l)
+	if l.Title != nil {
+		t.Errorf("title = %q while archive_title is still running, want null", *l.Title)
+	}
+
+	close(held.release)
+	if got := e.waitTitled(t); got != "Chili and Friends" {
+		t.Errorf("title = %q, want the title job's", got)
+	}
+}
+
+// TestSupplyRunGenerateDoesNotWaitForTitle: POST generate answers with the
+// list untitled while its title is still being written.
+func TestSupplyRunGenerateDoesNotWaitForTitle(t *testing.T) {
+	t.Parallel()
+	held := newHeldTitler()
+	e := newPlansRouterTitled(t, held.title)
+	e.groundWeek(t)
+	e.startRunner(t)
+
+	var l supplyRunJSON
+	if status, body := callShopping(t, e, http.MethodPost, shoppingPath+"2026-10-12/generate", "", &l); status != http.StatusOK {
+		t.Fatalf("generate = %d %v", status, body)
+	}
+	if l.Title != nil {
+		t.Errorf("title = %q while archive_title is still running, want null", *l.Title)
+	}
+	if !reflect.DeepEqual(l.render(), weekLines) {
+		t.Errorf("generated = %v, want %v", l.render(), weekLines)
+	}
+	held.waitEntered(t)
+
+	close(held.release)
+	if got := e.waitTitled(t); got != "Chili and Friends" {
+		t.Errorf("title = %q, want the title job's", got)
+	}
+}
+
 // TestFailedPushMakesNoSupplyRun: a push Calendar refused makes no Supply
 // run.
 func TestFailedPushMakesNoSupplyRun(t *testing.T) {
@@ -509,3 +639,151 @@ func TestPushPlanLeavesArchivedSupplyRun(t *testing.T) {
 		t.Errorf("archived Supply run after push = %v, want unchanged", l.render())
 	}
 }
+
+// archiveJSON is a GET /shopping/archive answer decoded with every field
+// the API promises.
+type archiveJSON struct {
+	By      string `json:"by"`
+	Periods []struct {
+		Key     string `json:"key"`
+		Heading string `json:"heading"`
+		Posts   []struct {
+			WeekStart   string   `json:"weekStart"`
+			Label       string   `json:"label"`
+			Title       *string  `json:"title"`
+			DinnerCount int      `json:"dinnerCount"`
+			ItemCount   int      `json:"itemCount"`
+			OnHandCount int      `json:"onHandCount"`
+			Dinners     []string `json:"dinners"`
+			Current     bool     `json:"current"`
+		} `json:"posts"`
+	} `json:"periods"`
+}
+
+// weekSupplyRun plans a new dinner named name, grounded in a recipe
+// listing ings, on the Monday of the week starting monday, and generates
+// the week's Supply run.
+func (e plansEnv) weekSupplyRun(t *testing.T, monday store.LocalDate, name string, ings ...shopIng) supplyRunJSON {
+	t.Helper()
+	q := db.New(e.st.Writer)
+	now := store.Now().String()
+	d, err := q.CreateDinner(t.Context(), db.CreateDinnerParams{
+		ID: store.NewID(), Name: name, NormalizedName: harness.Normalize(name), Status: "regular", Origin: "regular",
+		GroundingStatus: "manual", CreatedAt: now, UpdatedAt: now,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	planID := store.NewID()
+	if err := q.CreateWeekPlan(t.Context(), db.CreateWeekPlanParams{ID: planID, WeekStart: monday.String(), CreatedAt: now, UpdatedAt: now}); err != nil {
+		t.Fatal(err)
+	}
+	if err := q.PutPlanDay(t.Context(), db.PutPlanDayParams{ID: store.NewID(), PlanID: planID, Date: monday.String(),
+		DinnerID: sql.NullString{String: d.ID, Valid: true}, CreatedAt: now, UpdatedAt: now}); err != nil {
+		t.Fatal(err)
+	}
+	e.groundDay(t, monday.String(), ings...)
+	var l supplyRunJSON
+	if status, body := callShopping(t, e, http.MethodPost, shoppingPath+monday.String()+"/generate", "", &l); status != http.StatusOK {
+		t.Fatalf("generate %s = %d %v", monday, status, body)
+	}
+	return l
+}
+
+// TestSupplyArchive freezes last week's Supply run and reads the Supply
+// archive: posts newest first with exactly the promised fields, this
+// week's marked current. The frozen list is served read-only.
+func TestSupplyArchive(t *testing.T) {
+	t.Parallel()
+	e := newPlansRouter(t)
+	// The fixture's plan is for a fixed week; this test plans weeks
+	// around today instead.
+	if _, err := e.st.Writer.ExecContext(t.Context(), `DELETE FROM plan_days; DELETE FROM week_plans`); err != nil {
+		t.Fatal(err)
+	}
+	zone, err := household.LoadZone("America/New_York") // the env's household zone
+	if err != nil {
+		t.Fatal(err)
+	}
+	thisWeek := household.WeekStart(household.Today(time.Now(), zone))
+	y, m, d := thisWeek.Date()
+	lastWeek := store.LocalDateOf(time.Date(y, m, d-7, 0, 0, 0, 0, time.UTC))
+
+	last := e.weekSupplyRun(t, lastWeek, "Beef Stew", shopIng{"stewing beef", "2", "lb"}, shopIng{"carrots", "4", ""}, shopIng{"onion", "1", ""})
+	onion := last.itemID(t, "onion")
+	if status, body := callShopping(t, e, http.MethodPatch, shoppingPath+"items/"+onion, `{"needed":false}`, nil); status != http.StatusOK {
+		t.Fatalf("PATCH = %d %v", status, body)
+	}
+	e.weekSupplyRun(t, thisWeek, "Lemon Chicken", shopIng{"chicken thighs", "6", ""}, shopIng{"lemon", "1", ""})
+	if err := e.shop.Freeze(t.Context(), lastWeek); err != nil {
+		t.Fatal(err)
+	}
+	if err := e.shop.Freeze(t.Context(), thisWeek); !errors.Is(err, shopping.ErrWeekNotEnded) {
+		t.Fatalf("Freeze this week = %v, want ErrWeekNotEnded", err)
+	}
+
+	var got archiveJSON
+	status, raw := callShopping(t, e, http.MethodGet, shoppingPath+"archive?by=week", "", &got)
+	if status != http.StatusOK {
+		t.Fatalf("GET archive = %d %v", status, raw)
+	}
+	if k := keys(raw); !reflect.DeepEqual(k, []string{"by", "periods"}) {
+		t.Errorf("archive fields = %v", k)
+	}
+	period := raw["periods"].([]any)[0].(map[string]any)
+	if k := keys(period); !reflect.DeepEqual(k, []string{"heading", "key", "posts"}) {
+		t.Errorf("period fields = %v", k)
+	}
+	wantPost := []string{"current", "dinnerCount", "dinners", "itemCount", "label", "onHandCount", "title", "weekStart"}
+	if k := keys(period["posts"].([]any)[0].(map[string]any)); !reflect.DeepEqual(k, wantPost) {
+		t.Errorf("post fields = %v, want %v", k, wantPost)
+	}
+	var posts []string
+	for _, p := range got.Periods {
+		if len(p.Posts) != 1 || p.Key != household.PeriodKey(mustLocalDate(t, p.Posts[0].WeekStart)) || p.Heading != p.Posts[0].Label {
+			t.Errorf("period %+v, want one post under its week", p)
+		}
+		for _, post := range p.Posts {
+			label, err := household.WeekLabel(mustLocalDate(t, post.WeekStart))
+			if err != nil {
+				t.Fatal(err)
+			}
+			if post.Label != label || post.Title != nil {
+				t.Errorf("post %s: label %q title %v, want %q and null", post.WeekStart, post.Label, post.Title, label)
+			}
+			posts = append(posts, fmt.Sprintf("%s %d dinners %d items %d on hand %v current=%t",
+				post.WeekStart, post.DinnerCount, post.ItemCount, post.OnHandCount, post.Dinners, post.Current))
+		}
+	}
+	want := []string{
+		thisWeek.String() + " 1 dinners 2 items 0 on hand [Lemon Chicken] current=true",
+		lastWeek.String() + " 1 dinners 3 items 1 on hand [Beef Stew] current=false",
+	}
+	if got.By != "week" || !reflect.DeepEqual(posts, want) {
+		t.Errorf("archive by %s =\n  %s\nwant\n  %s", got.By, strings.Join(posts, "\n  "), strings.Join(want, "\n  "))
+	}
+
+	for _, q := range []string{"", "?by=", "?by=day", "?by=MONTH"} {
+		status, body := callShopping(t, e, http.MethodGet, shoppingPath+"archive"+q, "", nil)
+		if status != http.StatusBadRequest || errorCode(body) != "invalid_request" {
+			t.Errorf("GET archive%s = %d %v, want 400 invalid_request", q, status, body)
+		}
+	}
+
+	status, body := callShopping(t, e, http.MethodPatch, shoppingPath+"items/"+last.itemID(t, "carrots"), `{"needed":false}`, nil)
+	if status != http.StatusConflict || errorCode(body) != "archived" {
+		t.Errorf("PATCH after Freeze = %d %v, want 409 archived", status, body)
+	}
+	var frozen supplyRunJSON
+	if status, body := callShopping(t, e, http.MethodGet, shoppingPath+lastWeek.String(), "", &frozen); status != http.StatusOK {
+		t.Fatalf("GET frozen list = %d %v", status, body)
+	}
+	wantLines := []string{
+		"Monday " + lastWeek.String() + " Beef Stew: stewing beef [2 lb] needed",
+		"Monday " + lastWeek.String() + " Beef Stew: carrots [4] needed",
+		"Monday " + lastWeek.String() + " Beef Stew: onion [1] have it",
+	}
+	if frozen.Status != "archived" || frozen.NeededCount != 2 || frozen.TotalCount != 3 || !reflect.DeepEqual(frozen.render(), wantLines) {
+		t.Errorf("frozen list = %s %d/%d %v, want archived 2/3 %v", frozen.Status, frozen.NeededCount, frozen.TotalCount, frozen.render(), wantLines)
+	}
+}

internal/shopping/archive.go

@@ -0,0 +1,232 @@
+package shopping
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"fmt"
+	"strconv"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
+)
+
+// Archive groupings: the period Archive groups its posts by.
+const (
+	ByWeek  = "week"
+	ByMonth = "month"
+	ByYear  = "year"
+)
+
+// Freeze moves the Supply run of the week starting weekStart into the
+// Supply archive: its status becomes archived and frozen_at is set, after
+// which it is read-only (Generate and SetNeeded are ErrFrozen). Freezing a
+// frozen list does nothing and is no error.
+//
+// The week must have ended in the household's time zone: a week not yet
+// ended is ErrWeekNotEnded, and a week with no Supply run ErrListNotFound.
+//
+// A list still untitled is titled first, with archive_title and the same
+// conditional write as a KindTitleSupplyRun job, from the week's plan as
+// Generate titles it, so its post in the Supply archive gets a title when
+// the AI can write one. Titling never fails the freeze: a title that
+// cannot be written is logged and the list is frozen untitled, when its
+// week label stands in for the title for good. Freeze first waits for the
+// title jobs in flight to store their titles or fail, and holds off new
+// ones until the list is frozen, so a title a job's archive_title run
+// wrote is stored before the freeze, and the freeze runs archive_title
+// only when no job is running it. A job that runs after the freeze finds
+// the list titled, or frozen untitled, and stores nothing.
+func (s *Service) Freeze(ctx context.Context, weekStart store.LocalDate) error {
+	if _, err := household.WeekDays(weekStart); err != nil {
+		return fmt.Errorf("shopping: freeze: %w", err)
+	}
+	q := db.New(s.st.Writer)
+	thisWeek, err := s.thisWeek(ctx, q)
+	if err != nil {
+		return err
+	}
+	if weekStart.String() >= thisWeek.String() {
+		return fmt.Errorf("shopping: freeze %s: %w", weekStart, ErrWeekNotEnded)
+	}
+	s.titling.Lock()
+	defer s.titling.Unlock()
+	list, err := q.GetShoppingList(ctx, weekStart.String())
+	if errors.Is(err, sql.ErrNoRows) {
+		return ErrListNotFound
+	}
+	if err != nil {
+		return fmt.Errorf("shopping: freeze: read list: %w", err)
+	}
+	if frozen(list) {
+		return nil
+	}
+	if !list.Title.Valid {
+		p, err := freezeTitleJob(ctx, q, list)
+		if err != nil {
+			return err
+		}
+		if _, err := s.storeTitle(ctx, p); err != nil {
+			s.logger.WarnContext(ctx, "Supply run frozen untitled; the Supply archive shows its week label",
+				"week", list.WeekStart, "list", list.ID, "error", err)
+		}
+	}
+	// A list frozen meanwhile is left as it is: the freeze is done.
+	now := store.Now().String()
+	if _, err := q.FreezeShoppingList(ctx, db.FreezeShoppingListParams{
+		FrozenAt: sql.NullString{String: now, Valid: true}, UpdatedAt: now, ID: list.ID,
+	}); err != nil {
+		return fmt.Errorf("shopping: freeze %s: %w", weekStart, err)
+	}
+	return nil
+}
+
+// freezeTitleJob is the title job of list as Generate would enqueue it:
+// the week's plan revision and its dinners in day order.
+func freezeTitleJob(ctx context.Context, q *db.Queries, list db.ShoppingList) (TitleJob, error) {
+	plan, err := q.GetWeekPlan(ctx, list.WeekStart)
+	if err != nil {
+		return TitleJob{}, fmt.Errorf("shopping: freeze: read plan: %w", err)
+	}
+	days, err := q.ListPlanDays(ctx, plan.ID)
+	if err != nil {
+		return TitleJob{}, fmt.Errorf("shopping: freeze: read plan days: %w", err)
+	}
+	names := make([]string, len(days))
+	for i, d := range days {
+		names[i] = d.Dinner.Name
+	}
+	return TitleJob{ListID: list.ID, WeekStart: list.WeekStart, Revision: plan.Revision, Dinners: names}, nil
+}
+
+// thisWeek returns the Monday of the household's current week, in its
+// time zone, by the service's clock.
+func (s *Service) thisWeek(ctx context.Context, q *db.Queries) (store.LocalDate, error) {
+	settings, err := q.GetHouseholdSettings(ctx)
+	if err != nil {
+		return store.LocalDate{}, fmt.Errorf("shopping: read household settings: %w", err)
+	}
+	zone, err := household.LoadZone(settings.Timezone)
+	if err != nil {
+		return store.LocalDate{}, fmt.Errorf("shopping: household settings: %w", err)
+	}
+	return household.WeekStart(household.Today(s.now(), zone)), nil
+}
+
+// Period is one heading of the Supply archive and its posts, newest first.
+type Period struct {
+	// Key identifies the period: the ISO week ("2026-W41"), the month
+	// ("2026-10") or the year ("2026").
+	Key string
+	// Heading is the period as shown: the week label, the month and year
+	// ("October 2026") or the year ("2026").
+	Heading string
+	Posts   []Post
+}
+
+// Post is one Supply run in the Supply archive.
+type Post struct {
+	WeekStart string
+	// Label is the week label, such as "Week 41 · Oct 5 – 11".
+	Label string
+	// Title is nil while the list is untitled, when Label stands in.
+	Title *string
+	// Dinners are the names of the list's dinners, in day order.
+	Dinners []string
+	// Items is how many items the list has, and OnHand how many of them
+	// the household marked "have it".
+	Items, OnHand int
+	// Current is true for the household's current week.
+	Current bool
+}
+
+// Archive returns the Supply archive: the Supply run of every week up to
+// and including the household's current week, newest first, grouped by
+// by, which is ByWeek, ByMonth or ByYear (else ErrInvalidPeriod). A
+// week's month and year are those of its Monday, a household-local date,
+// so a week belongs to one period whatever the server's zone; the week
+// starting Monday 2026-12-28 is in December 2026.
+func (s *Service) Archive(ctx context.Context, by string) (out []Period, err error) {
+	// period returns the key and heading of the period holding p, whose
+	// week starts on Monday monday.
+	var period func(monday store.LocalDate, p Post) (string, string)
+	switch by {
+	case ByWeek:
+		period = func(monday store.LocalDate, p Post) (string, string) {
+			return household.PeriodKey(monday), p.Label
+		}
+	case ByMonth:
+		period = func(monday store.LocalDate, _ Post) (string, string) {
+			y, m, _ := monday.Date()
+			return fmt.Sprintf("%04d-%02d", y, int(m)), fmt.Sprintf("%s %d", m, y)
+		}
+	case ByYear:
+		period = func(monday store.LocalDate, _ Post) (string, string) {
+			y, _, _ := monday.Date()
+			return strconv.Itoa(y), strconv.Itoa(y)
+		}
+	default:
+		return nil, fmt.Errorf("shopping: archive by %q: %w", by, ErrInvalidPeriod)
+	}
+	tx, err := s.st.Reader.BeginTx(ctx, nil)
+	if err != nil {
+		return nil, fmt.Errorf("shopping: begin read: %w", err)
+	}
+	defer func() {
+		err = errors.Join(err, tx.Rollback())
+	}()
+	q := db.New(tx)
+	thisWeek, err := s.thisWeek(ctx, q)
+	if err != nil {
+		return nil, err
+	}
+	lists, err := q.ListShoppingListsThrough(ctx, thisWeek.String())
+	if err != nil {
+		return nil, fmt.Errorf("shopping: read Supply runs: %w", err)
+	}
+	out = []Period{}
+	for _, row := range lists {
+		monday, err := store.ParseLocalDate(row.WeekStart)
+		if err != nil {
+			return nil, fmt.Errorf("shopping: Supply run %s week: %w", row.ID, err)
+		}
+		l, err := readList(ctx, q, row)
+		if err != nil {
+			return nil, err
+		}
+		p, err := postOf(monday, l, monday == thisWeek)
+		if err != nil {
+			return nil, err
+		}
+		k, heading := period(monday, p)
+		if n := len(out); n == 0 || out[n-1].Key != k {
+			out = append(out, Period{Key: k, Heading: heading})
+		}
+		out[len(out)-1].Posts = append(out[len(out)-1].Posts, p)
+	}
+	return out, nil
+}
+
+// postOf is l, the Supply run of the week starting monday, as a post in
+// the Supply archive.
+func postOf(monday store.LocalDate, l List, current bool) (Post, error) {
+	label, err := household.WeekLabel(monday)
+	if err != nil {
+		return Post{}, fmt.Errorf("shopping: Supply run %s: %w", l.ID, err)
+	}
+	dinners := make([]string, len(l.Groups))
+	for i, g := range l.Groups {
+		dinners[i] = g.DinnerName
+	}
+	c := l.Counts()
+	return Post{
+		WeekStart: l.WeekStart,
+		Label:     label,
+		Title:     l.Title,
+		Dinners:   dinners,
+		Items:     c.Total,
+		OnHand:    c.Total - c.Needed,
+		Current:   current,
+	}, nil
+}

internal/shopping/archive_test.go

@@ -0,0 +1,477 @@
+package shopping_test
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"reflect"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/jobs"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/shopping"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
+)
+
+// zoned makes zone the household's time zone and at the instant the
+// service's clock reads.
+func (e *env) zoned(t *testing.T, zone, at string) {
+	t.Helper()
+	if err := household.SeedSettings(t.Context(), e.st, zone); err != nil {
+		t.Fatal(err)
+	}
+	e.at(t, at)
+}
+
+// at sets the service's clock to the RFC 3339 instant at.
+func (e *env) at(t *testing.T, at string) {
+	t.Helper()
+	now, err := time.Parse(time.RFC3339, at)
+	if err != nil {
+		t.Fatal(err)
+	}
+	shopping.SetClock(e.svc, func() time.Time { return now })
+}
+
+// frozenState returns the week's list's status and frozen_at; frozen_at is
+// "" while NULL.
+func (e *env) frozenState(t *testing.T, monday store.LocalDate) (string, string) {
+	t.Helper()
+	var status string
+	var frozenAt sql.NullString
+	if err := e.st.Reader.QueryRow(`SELECT status, frozen_at FROM shopping_lists WHERE week_start = ?`, monday.String()).Scan(&status, &frozenAt); err != nil {
+		t.Fatal(err)
+	}
+	return status, frozenAt.String
+}
+
+// weekList plans the dinners named names on the days of the week starting
+// monday, in order, and generates its Supply run.
+func (e *env) weekList(t *testing.T, monday string, names ...string) shopping.List {
+	t.Helper()
+	start := mustDate(monday)
+	days, err := household.WeekDays(start)
+	if err != nil {
+		t.Fatal(err)
+	}
+	q := db.New(e.st.Writer)
+	now := store.Now().String()
+	planID := store.NewID()
+	if err := q.CreateWeekPlan(t.Context(), db.CreateWeekPlanParams{ID: planID, WeekStart: monday, CreatedAt: now, UpdatedAt: now}); err != nil {
+		t.Fatal(err)
+	}
+	for i, name := range names {
+		if err := q.PutPlanDay(t.Context(), db.PutPlanDayParams{
+			ID: store.NewID(), PlanID: planID, Date: days[i].String(),
+			DinnerID: sql.NullString{String: e.ids[name], Valid: true}, CreatedAt: now, UpdatedAt: now,
+		}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	g, err := e.svc.Generate(t.Context(), start)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return g.List
+}
+
+// endedWeek is the env with the tests' week generated, in New York, on
+// the Monday after it, so the week has ended.
+func endedWeek(t *testing.T) (*env, shopping.List) {
+	t.Helper()
+	e := newEnv(t)
+	e.zoned(t, "America/New_York", "2026-10-19T12:00:00Z")
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"}, ing{"onion", "1", ""})
+	e.plan(t, "Beef Chili")
+	return e, e.generate(t).List
+}
+
+// TestFreeze freezes an ended week's list: it is archived with frozen_at,
+// read back read-only, and freezing it again changes nothing.
+func TestFreeze(t *testing.T) {
+	e, l := endedWeek(t)
+
+	if err := e.svc.Freeze(t.Context(), week); err != nil {
+		t.Fatal(err)
+	}
+	status, frozenAt := e.frozenState(t, week)
+	if status != shopping.StatusArchived || frozenAt == "" {
+		t.Fatalf("after Freeze: status %q, frozen_at %q; want archived and set", status, frozenAt)
+	}
+	got, err := e.svc.Get(t.Context(), week)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got.Status != shopping.StatusArchived {
+		t.Errorf("read back status = %q, want archived", got.Status)
+	}
+	wantLines(t, "read back", lines(got), []string{
+		"0 2026-10-12 Beef Chili: 0 ground beef [1 lb] needed",
+		"0 2026-10-12 Beef Chili: 1 onion [1] needed",
+	})
+
+	time.Sleep(2 * time.Millisecond) // a second freeze would stamp a later frozen_at
+	if err := e.svc.Freeze(t.Context(), week); err != nil {
+		t.Fatalf("second Freeze = %v, want no error", err)
+	}
+	if s, again := e.frozenState(t, week); s != shopping.StatusArchived || again != frozenAt {
+		t.Errorf("after second Freeze: status %q, frozen_at %q; want archived, %q kept", s, again, frozenAt)
+	}
+
+	if _, err := e.svc.SetNeeded(t.Context(), l.Groups[0].Items[1].ID, false); !errors.Is(err, shopping.ErrFrozen) {
+		t.Errorf("SetNeeded after Freeze = %v, want ErrFrozen", err)
+	}
+	if _, err := e.svc.Generate(t.Context(), week); !errors.Is(err, shopping.ErrFrozen) {
+		t.Errorf("Generate after Freeze = %v, want ErrFrozen", err)
+	}
+	wantLines(t, "stored list", e.stored(t), []string{
+		"0 2026-10-12 Beef Chili: 0 ground beef [1 lb] needed",
+		"0 2026-10-12 Beef Chili: 1 onion [1] needed",
+	})
+}
+
+// TestFreezeWeekNotEnded: a week has not ended until Monday comes in the
+// household's zone. At 23:30 on the Sunday in Los Angeles it is already
+// Monday in UTC, and the list is still not frozen; at 00:05 on the Monday
+// it is.
+func TestFreezeWeekNotEnded(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "America/Los_Angeles", "2026-10-19T06:30:00Z") // Sun 18 Oct 23:30 PDT
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"})
+	e.plan(t, "Beef Chili")
+	e.generate(t)
+
+	if err := e.svc.Freeze(t.Context(), week); !errors.Is(err, shopping.ErrWeekNotEnded) {
+		t.Fatalf("Freeze on the Sunday = %v, want ErrWeekNotEnded", err)
+	}
+	if status, frozenAt := e.frozenState(t, week); status != shopping.StatusCurrent || frozenAt != "" {
+		t.Fatalf("after refused Freeze: status %q, frozen_at %q; want current, unset", status, frozenAt)
+	}
+	if err := e.svc.Freeze(t.Context(), mustDate("2026-10-19")); !errors.Is(err, shopping.ErrWeekNotEnded) {
+		t.Errorf("Freeze of a later week = %v, want ErrWeekNotEnded", err)
+	}
+
+	e.at(t, "2026-10-19T07:05:00Z") // Mon 19 Oct 00:05 PDT
+	if err := e.svc.Freeze(t.Context(), week); err != nil {
+		t.Fatalf("Freeze on the Monday = %v", err)
+	}
+	if status, _ := e.frozenState(t, week); status != shopping.StatusArchived {
+		t.Errorf("status = %q, want archived", status)
+	}
+}
+
+func TestFreezeWeekWithoutList(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "America/New_York", "2026-10-19T12:00:00Z")
+	if err := e.svc.Freeze(t.Context(), week); !errors.Is(err, shopping.ErrListNotFound) {
+		t.Fatalf("Freeze = %v, want ErrListNotFound", err)
+	}
+	if err := e.svc.Freeze(t.Context(), mustDate("2026-10-13")); err == nil {
+		t.Fatal("Freeze of a Tuesday succeeded")
+	}
+}
+
+// TestFreezeTitlesUntitledList: a list still untitled when its week is
+// frozen is titled by archive_title first, from the plan's dinners, and
+// frozen with that title. Its title job, still queued, runs after the
+// freeze, finds the title and succeeds without asking the model again.
+func TestFreezeTitlesUntitledList(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "America/New_York", "2026-10-19T12:00:00Z")
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"})
+	e.dinner(t, "Fish Tacos")
+	e.plan(t, "Fish Tacos", "Beef Chili")
+	g := e.generate(t) // the runner is not started: its title job waits
+	e.model.QueueGenerate(titled("Tacos then Chili"))
+
+	if err := e.svc.Freeze(t.Context(), week); err != nil {
+		t.Fatal(err)
+	}
+	wantTitle(t, "stored title", e.storedTitle(t), "Tacos then Chili")
+	if status, frozenAt := e.frozenState(t, week); status != shopping.StatusArchived || frozenAt == "" {
+		t.Errorf("status %q, frozen_at %q; want archived and set", status, frozenAt)
+	}
+	reqs := e.model.Requests()
+	if len(reqs) != 1 {
+		t.Fatalf("%d model calls, want 1", len(reqs))
+	}
+	if want := "Title the week whose dinners are, in day order from Monday:\n- Fish Tacos\n- Beef Chili"; reqs[0].Messages[0].Content != want {
+		t.Errorf("user message = %q, want %q", reqs[0].Messages[0].Content, want)
+	}
+
+	e.start(t)
+	wantJob(t, e.waitTitle(t, g), jobs.StatusSucceeded, "")
+	if n := len(e.model.Requests()); n != 1 {
+		t.Errorf("%d model calls, want 1: the job finds the list titled", n)
+	}
+	wantTitle(t, "stored title after the job", e.storedTitle(t), "Tacos then Chili")
+}
+
+// pauseTitle makes the env's first archive_title run pause once it has
+// returned, before its title is stored, until the returned release is
+// called or the test ends; paused is closed as it pauses.
+func (e *env) pauseTitle(t *testing.T) (paused <-chan struct{}, release func()) {
+	t.Helper()
+	p, r := make(chan struct{}), make(chan struct{})
+	var first atomic.Bool
+	e.afterTitle = func() {
+		if first.CompareAndSwap(false, true) {
+			close(p)
+			select {
+			case <-r:
+			case <-t.Context().Done():
+			}
+		}
+	}
+	var released sync.Once
+	return p, func() { released.Do(func() { close(r) }) }
+}
+
+// waitClosed fails t unless c is closed within 10 seconds.
+func waitClosed(t *testing.T, what string, c <-chan struct{}) {
+	t.Helper()
+	select {
+	case <-c:
+	case <-time.After(10 * time.Second):
+		t.Fatalf("timed out waiting for %s", what)
+	}
+}
+
+// TestFreezeWaitsForTitleJob: a freeze that starts while a title job's
+// archive_title run has returned but its title is not yet stored waits for
+// the job to store it, freezes the list with that title, and asks the
+// model nothing itself.
+func TestFreezeWaitsForTitleJob(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "America/New_York", "2026-10-19T12:00:00Z")
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"})
+	e.plan(t, "Beef Chili")
+	e.model.QueueGenerate(titled("Chili Night"))
+	paused, release := e.pauseTitle(t)
+	e.start(t)
+	g := e.generate(t)
+	waitClosed(t, "the title job's archive_title run", paused)
+
+	froze := make(chan error, 1)
+	go func() { froze <- e.svc.Freeze(context.Background(), week) }()
+	var err error
+	select {
+	case err = <-froze:
+		t.Errorf("Freeze = %v before the title job stored its title, want it to wait", err)
+		release()
+	case <-time.After(time.Second):
+		release()
+		err = <-froze
+	}
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	wantJob(t, e.waitTitle(t, g), jobs.StatusSucceeded, "")
+	wantTitle(t, "stored title", e.storedTitle(t), "Chili Night")
+	if status, _ := e.frozenState(t, week); status != shopping.StatusArchived {
+		t.Errorf("status = %q, want archived", status)
+	}
+	if n := len(e.model.Requests()); n != 1 {
+		t.Errorf("%d model calls, want 1: the freeze waits for the job's title", n)
+	}
+}
+
+// TestTitleJobWaitsForFreeze: a title job that starts while a freeze's
+// archive_title run has returned but its title is not yet stored waits for
+// the freeze, then finds the list titled and asks the model nothing.
+func TestTitleJobWaitsForFreeze(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "America/New_York", "2026-10-19T12:00:00Z")
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"})
+	e.plan(t, "Beef Chili")
+	e.model.QueueGenerate(titled("Chili Night"))
+	g := e.generate(t) // the runner is not started: its title job waits
+	paused, release := e.pauseTitle(t)
+
+	froze := make(chan error, 1)
+	go func() { froze <- e.svc.Freeze(context.Background(), week) }()
+	waitClosed(t, "the freeze's archive_title run", paused)
+	e.start(t)
+	deadline := time.Now().Add(10 * time.Second)
+	for {
+		job, err := e.runner.Get(t.Context(), *g.TitleJobID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if job.Status == jobs.StatusRunning {
+			break
+		}
+		if job.Status != jobs.StatusQueued || time.Now().After(deadline) {
+			t.Fatalf("title job %s, want it running while the freeze is paused", job.Status)
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+	release()
+	if err := <-froze; err != nil {
+		t.Fatal(err)
+	}
+
+	wantJob(t, e.waitTitle(t, g), jobs.StatusSucceeded, "")
+	wantTitle(t, "stored title", e.storedTitle(t), "Chili Night")
+	if status, _ := e.frozenState(t, week); status != shopping.StatusArchived {
+		t.Errorf("status = %q, want archived", status)
+	}
+	if n := len(e.model.Requests()); n != 1 {
+		t.Errorf("%d model calls, want 1: the job waits for the freeze's title", n)
+	}
+}
+
+// TestFreezeUntitledWhenTitleFails: when archive_title cannot title the
+// list, it is frozen untitled all the same, the failure is logged, and the
+// Supply archive shows its week label for good.
+func TestFreezeUntitledWhenTitleFails(t *testing.T) {
+	e, _ := endedWeek(t) // nothing queued on the model: archive_title fails
+
+	if err := e.svc.Freeze(t.Context(), week); err != nil {
+		t.Fatal(err)
+	}
+	wantUntitled(t, "stored title", e.storedTitle(t))
+	if status, _ := e.frozenState(t, week); status != shopping.StatusArchived {
+		t.Errorf("status = %q, want archived", status)
+	}
+	if !strings.Contains(e.log.String(), "Supply run frozen untitled") {
+		t.Errorf("log lacks the failure:\n%s", e.log.String())
+	}
+	periods, err := e.svc.Archive(t.Context(), shopping.ByWeek)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(periods) != 1 || len(periods[0].Posts) != 1 || periods[0].Posts[0].Title != nil ||
+		periods[0].Posts[0].Label != "Week 42 · Oct 12 – 18" {
+		t.Errorf("archive = %+v, want the untitled week under its label", periods)
+	}
+}
+
+// TestFreezeKeepsTitle: a titled list is frozen with its title and the
+// model is not asked again.
+func TestFreezeKeepsTitle(t *testing.T) {
+	e, _ := endedWeek(t)
+	if _, err := e.st.Writer.Exec(`UPDATE shopping_lists SET title = 'Chili Night'`); err != nil {
+		t.Fatal(err)
+	}
+	if err := e.svc.Freeze(t.Context(), week); err != nil {
+		t.Fatal(err)
+	}
+	wantTitle(t, "stored title", e.storedTitle(t), "Chili Night")
+	if n := len(e.model.Requests()); n != 0 {
+		t.Errorf("%d model calls, want none", n)
+	}
+}
+
+// postLine renders p as "weekStart label | title | dinners | items/on hand
+// | current".
+func postLine(p shopping.Post) string {
+	title := "-"
+	if p.Title != nil {
+		title = *p.Title
+	}
+	cur := ""
+	if p.Current {
+		cur = " | current"
+	}
+	return p.WeekStart + " " + p.Label + " | " + title + " | " + strings.Join(p.Dinners, ", ") + " | " +
+		strconv.Itoa(p.Items) + " items, " + strconv.Itoa(p.OnHand) + " on hand" + cur
+}
+
+// periodLines renders periods one line per heading and post.
+func periodLines(periods []shopping.Period) []string {
+	var out []string
+	for _, p := range periods {
+		out = append(out, "# "+p.Key+" "+p.Heading)
+		for _, post := range p.Posts {
+			out = append(out, postLine(post))
+		}
+	}
+	return out
+}
+
+// TestArchiveGroups reads the Supply archive across a month and a year
+// boundary in Auckland, where it is already Monday 4 January 2027 while
+// UTC still reads Sunday 3 January: that week is current, the next one is
+// not yet in the archive, and each week falls in the month and year of
+// its Monday.
+func TestArchiveGroups(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "Pacific/Auckland", "2027-01-03T12:00:00Z") // Mon 4 Jan 2027 01:00 NZDT
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"}, ing{"onion", "1", ""}, ing{"kidney beans", "2", "cans"})
+	e.dinner(t, "Pad Thai", ing{"rice noodles", "8", "oz"}, ing{"lime", "2", ""})
+	e.dinner(t, "Fish Tacos") // no recipe: no group, not counted
+	e.dinner(t, "Pot Roast", ing{"carrots", "4", ""})
+
+	nov := e.weekList(t, "2026-11-30", "Pot Roast") // Nov 30 – Dec 6
+	e.weekList(t, "2026-12-07", "Pad Thai", "Fish Tacos")
+	dec := e.weekList(t, "2026-12-28", "Beef Chili", "Fish Tacos", "Pad Thai") // ISO 2026-W53, into January
+	jan := e.weekList(t, "2027-01-04", "Pad Thai", "Beef Chili")
+	e.weekList(t, "2027-01-11", "Pot Roast") // next week: not in the archive yet
+	e.haveIt(t, dec, "Beef Chili", "onion")
+	e.haveIt(t, dec, "Pad Thai", "lime")
+	e.haveIt(t, jan, "Pad Thai", "lime")
+	e.haveIt(t, nov, "Pot Roast", "carrots")
+	if _, err := e.st.Writer.Exec(`UPDATE shopping_lists SET title = 'Chili, Noodles & Co' WHERE week_start = '2026-12-28'`); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := e.st.Writer.Exec(`UPDATE shopping_lists SET status = 'archived', frozen_at = '2027-01-03T11:05:00.000Z' WHERE week_start < '2027-01-04'`); err != nil {
+		t.Fatal(err)
+	}
+
+	posts := map[string]string{
+		"jan": "2027-01-04 Week 1 · Jan 4 – 10 | - | Pad Thai, Beef Chili | 5 items, 1 on hand | current",
+		"dec": "2026-12-28 Week 53 · Dec 28 – Jan 3 | Chili, Noodles & Co | Beef Chili, Pad Thai | 5 items, 2 on hand",
+		"d07": "2026-12-07 Week 50 · Dec 7 – 13 | - | Pad Thai | 2 items, 0 on hand",
+		"nov": "2026-11-30 Week 49 · Nov 30 – Dec 6 | - | Pot Roast | 1 items, 1 on hand",
+	}
+	for _, tc := range []struct {
+		by   string
+		want []string
+	}{
+		{shopping.ByWeek, []string{
+			"# 2027-W01 Week 1 · Jan 4 – 10", posts["jan"],
+			"# 2026-W53 Week 53 · Dec 28 – Jan 3", posts["dec"],
+			"# 2026-W50 Week 50 · Dec 7 – 13", posts["d07"],
+			"# 2026-W49 Week 49 · Nov 30 – Dec 6", posts["nov"],
+		}},
+		{shopping.ByMonth, []string{
+			"# 2027-01 January 2027", posts["jan"],
+			"# 2026-12 December 2026", posts["dec"], posts["d07"],
+			"# 2026-11 November 2026", posts["nov"],
+		}},
+		{shopping.ByYear, []string{
+			"# 2027 2027", posts["jan"],
+			"# 2026 2026", posts["dec"], posts["d07"], posts["nov"],
+		}},
+	} {
+		got, err := e.svc.Archive(t.Context(), tc.by)
+		if err != nil {
+			t.Fatalf("Archive(%s): %v", tc.by, err)
+		}
+		if lines := periodLines(got); !reflect.DeepEqual(lines, tc.want) {
+			t.Errorf("Archive(%s) =\n  %s\nwant\n  %s", tc.by, strings.Join(lines, "\n  "), strings.Join(tc.want, "\n  "))
+		}
+	}
+}
+
+func TestArchiveEmptyAndInvalidPeriod(t *testing.T) {
+	e := newEnv(t)
+	e.zoned(t, "America/New_York", "2026-10-19T12:00:00Z")
+	got, err := e.svc.Archive(t.Context(), shopping.ByMonth)
+	if err != nil || got == nil || len(got) != 0 {
+		t.Errorf("Archive of no Supply runs = %#v, %v; want empty", got, err)
+	}
+	for _, by := range []string{"", "day", "Week", "months"} {
+		if _, err := e.svc.Archive(t.Context(), by); !errors.Is(err, shopping.ErrInvalidPeriod) {
+			t.Errorf("Archive(%q) = %v, want ErrInvalidPeriod", by, err)
+		}
+	}
+}

internal/shopping/export_test.go

@@ -0,0 +1,6 @@
+package shopping
+
+import "time"
+
+// SetClock makes now the clock s ends and dates weeks on.
+func SetClock(s *Service, now func() time.Time) { s.now = now }

internal/shopping/shopping.go

@@ -5,19 +5,32 @@
 // Generate makes a week's Supply run from its plan, and remakes it after
 // the plan changes. It is deterministic and runs no model: an item is one
 // ingredient of the dinner's recipe exactly as recipe grounding stored it
-// (see Generate).
+// (see Generate). The one model call is the Supply run's title, written by
+// archive_title in a KindTitleSupplyRun job when the list is generated
+// untitled (see Generate).
+//
+// Freeze moves a week's Supply run into the Supply archive once its week
+// has ended, and Archive reads the archive back as posts grouped by week,
+// month or year.
 package shopping
 
 import (
 	"context"
+	"crypto/sha256"
 	"database/sql"
+	"encoding/json"
 	"errors"
 	"fmt"
+	"log/slog"
 	"strings"
+	"sync"
+	"time"
 
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/skills"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/dinners"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/jobs"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
 )
 
@@ -36,6 +49,15 @@ const (
 	SkipNoIngredients = "no_ingredients"
 )
 
+// KindTitleSupplyRun is the job kind that titles a Supply run with
+// archive_title. Only Generate and GeneratePushed enqueue it.
+const KindTitleSupplyRun = "title_supply_run"
+
+// ReasonTitleFailed is the failure code of a KindTitleSupplyRun job that
+// stored no title: archive_title failed, or the Supply run was frozen or
+// replaced first. The Supply run stays untitled.
+const ReasonTitleFailed = "title_failed"
+
 // ErrPlanNotFound is a generation for a week with no plan.
 var ErrPlanNotFound = errors.New("the week has no plan")
 
@@ -54,17 +76,60 @@ var ErrListNotFound = errors.New("the week has no Supply run")
 // ErrItemNotFound is a change to an item on no Supply run.
 var ErrItemNotFound = errors.New("no Supply run has that item")
 
+// ErrWeekNotEnded is a freeze of a Supply run whose week has not ended in
+// the household's time zone.
+var ErrWeekNotEnded = errors.New("the week has not ended")
+
+// ErrInvalidPeriod is an Archive grouping other than ByWeek, ByMonth and
+// ByYear.
+var ErrInvalidPeriod = errors.New("by must be week, month or year")
+
+// Titler runs archive_title on in; scope names the week, its plan revision
+// and its dinners.
+// In production it is skills.TitleArchive with the household's
+// harness.Config.
+type Titler func(ctx context.Context, scope string, in skills.ArchiveTitleRequest) (skills.ArchiveTitle, error)
+
 // Service generates Supply runs.
 type Service struct {
-	st *store.Store
+	st       *store.Store
+	title    Titler
+	titleJob *jobs.Kind[TitleJob]
+	logger   *slog.Logger
+	// now is the clock weeks are ended and current on; tests replace it.
+	now func() time.Time
+	// titling orders the title writes against Freeze. A title job holds it
+	// shared from reading the list to storing its title, and Freeze holds
+	// it exclusively from reading the list to freezing it, so a freeze
+	// waits for the title jobs in flight to store their titles or fail,
+	// and no title job runs archive_title while a freeze is under way.
+	titling sync.RWMutex
 }
 
-// NewService returns a service over st.
-func NewService(st *store.Store) (*Service, error) {
-	if st == nil {
+// NewService returns a service over st that titles Supply runs with title
+// in KindTitleSupplyRun jobs, which it registers on runner, and logs to
+// logger. runner must not have started yet.
+func NewService(st *store.Store, title Titler, runner *jobs.Runner, logger *slog.Logger) (*Service, error) {
+	switch {
+	case st == nil:
 		return nil, errors.New("shopping: nil store")
+	case title == nil:
+		return nil, errors.New("shopping: nil titler")
+	case runner == nil:
+		return nil, errors.New("shopping: nil job runner")
+	case logger == nil:
+		return nil, errors.New("shopping: nil logger")
 	}
-	return &Service{st: st}, nil
+	s := &Service{st: st, title: title, logger: logger, now: time.Now}
+	kind, err := jobs.Register(runner, KindTitleSupplyRun, s.runTitleJob, ReasonTitleFailed)
+	if err != nil {
+		return nil, err
+	}
+	if err := kind.ServiceOnly(); err != nil {
+		return nil, err
+	}
+	s.titleJob = kind
+	return s, nil
 }
 
 // List is a Supply run.
@@ -142,6 +207,9 @@ type Generated struct {
 	// Skipped are the plan days whose dinner has no ingredients to shop
 	// for, by date.
 	Skipped []SkippedDay `json:"skipped"`
+	// TitleJobID is the KindTitleSupplyRun job titling the list; nil when
+	// the list already has its title.
+	TitleJobID *string `json:"title_job_id"`
 }
 
 // Generate makes the Supply run of the week starting weekStart from the
@@ -166,6 +234,16 @@ type Generated struct {
 // new and needed; an item no longer on the plan is removed, and with it a
 // group no longer on the plan.
 //
+// A list still untitled once it is stored, as a new list always is, gets a
+// KindTitleSupplyRun job, enqueued in the same transaction, that titles it
+// with archive_title from the names of the plan's dinners in day order.
+// Generate returns without waiting for the job: the list is returned
+// untitled, with the job's id. A title is written once: a remake keeps it
+// and enqueues no job. Titling never fails the generation: a title that
+// cannot be written leaves the list untitled, the failure is logged and
+// the job failed with ReasonTitleFailed, and the next generation of the
+// week, Generate or GeneratePushed, tries again.
+//
 // A week with no plan is ErrPlanNotFound; a list frozen into the Supply
 // archive is ErrFrozen. A fetched recipe's ingredient without a name is an
 // error: grounding always names one.
@@ -206,7 +284,7 @@ func (s *Service) generate(ctx context.Context, weekStart store.LocalDate, check
 		if err := check(plan); err != nil {
 			return err
 		}
-		want, skipped, err := wanted(ctx, q, plan.ID)
+		want, skipped, dinnerNames, err := wanted(ctx, q, plan.ID)
 		if err != nil {
 			return err
 		}
@@ -235,14 +313,126 @@ func (s *Service) generate(ctx context.Context, weekStart store.LocalDate, check
 			return err
 		}
 		out = Generated{List: listOf(list, groups), Skipped: skipped}
+		if list.Title.Valid {
+			return nil
+		}
+		id, err := s.titleJob.EnqueueTx(ctx, tx, TitleJob{
+			ListID: list.ID, WeekStart: list.WeekStart, Revision: plan.Revision, Dinners: dinnerNames,
+		})
+		if err != nil {
+			return fmt.Errorf("shopping: enqueue title: %w", err)
+		}
+		out.TitleJobID = &id
 		return nil
 	})
 	if err != nil {
 		return Generated{}, err
 	}
+	if out.TitleJobID != nil {
+		s.titleJob.Wake()
+	}
 	return out, nil
 }
 
+// TitleJob is a KindTitleSupplyRun job's payload: the untitled Supply run
+// ListID of the week WeekStart, made from the plan at Revision, whose
+// dinners in day order are Dinners.
+type TitleJob struct {
+	ListID    string   `json:"list_id"`
+	WeekStart string   `json:"week_start"`
+	Revision  int64    `json:"revision"`
+	Dinners   []string `json:"dinners"`
+}
+
+// titleResult is a KindTitleSupplyRun job's result: the Supply run and the
+// title it has.
+type titleResult struct {
+	ListID string `json:"list_id"`
+	Title  string `json:"title"`
+}
+
+// PublicJSON returns the Supply run's id and title.
+func (r titleResult) PublicJSON() ([]byte, error) { return json.Marshal(r) }
+
+// runTitleJob titles the Supply run of p with archive_title and stores the
+// title. A title that cannot be stored leaves the list untitled: the
+// failure is logged and the job fails with ReasonTitleFailed.
+func (s *Service) runTitleJob(ctx context.Context, p TitleJob, _ func(titleResult) error) (titleResult, error) {
+	title, err := s.writeTitle(ctx, p)
+	if err != nil {
+		s.logger.WarnContext(ctx, "Supply run left untitled; its next generation titles it again",
+			"week", p.WeekStart, "list", p.ListID, "error", err)
+		return titleResult{}, &jobs.Failure{Code: ReasonTitleFailed}
+	}
+	return titleResult{ListID: p.ListID, Title: title}, nil
+}
+
+// writeTitle runs archive_title for p's Supply run and stores its title,
+// as storeTitle does, while no freeze is under way: it waits for one to
+// end first, and a freeze waits for it to end.
+func (s *Service) writeTitle(ctx context.Context, p TitleJob) (string, error) {
+	s.titling.RLock()
+	defer s.titling.RUnlock()
+	return s.storeTitle(ctx, p)
+}
+
+// storeTitle runs archive_title for p's Supply run and stores its title.
+// When the list was titled by another job, before this one ran or
+// meanwhile, that title stands and is returned. The caller holds titling.
+func (s *Service) storeTitle(ctx context.Context, p TitleJob) (string, error) {
+	q := db.New(s.st.Writer)
+	title, err := s.currentTitle(ctx, q, p)
+	if err != nil || title != "" {
+		return title, err
+	}
+	out, err := s.title(ctx, titleScope(p), skills.ArchiveTitleRequest{Dinners: p.Dinners})
+	if err != nil {
+		return "", fmt.Errorf("shopping: title: %w", err)
+	}
+	write, cancel := jobs.FinalWriteContext(ctx)
+	defer cancel()
+	n, err := q.SetShoppingListTitle(write, db.SetShoppingListTitleParams{
+		Title: sql.NullString{String: out.Title, Valid: true}, UpdatedAt: store.Now().String(), ID: p.ListID,
+	})
+	if err != nil {
+		return "", fmt.Errorf("shopping: store title: %w", err)
+	}
+	if n == 1 {
+		return out.Title, nil
+	}
+	title, err = s.currentTitle(write, q, p)
+	if err == nil && title == "" {
+		err = errors.New("shopping: store title: the Supply run is still untitled")
+	}
+	return title, err
+}
+
+// currentTitle returns the title of p's Supply run, or "" while it is
+// untitled. A list frozen or replaced untitled is an error: it can no
+// longer be titled.
+func (s *Service) currentTitle(ctx context.Context, q *db.Queries, p TitleJob) (string, error) {
+	list, err := q.GetShoppingList(ctx, p.WeekStart)
+	if err != nil && !errors.Is(err, sql.ErrNoRows) {
+		return "", fmt.Errorf("shopping: title: read list: %w", err)
+	}
+	switch {
+	case err == nil && list.ID == p.ListID && list.Title.Valid:
+		return list.Title.String, nil
+	case err != nil || list.ID != p.ListID || frozen(list):
+		return "", errors.New("shopping: store title: the Supply run was frozen or replaced before its title was stored")
+	}
+	return "", nil
+}
+
+// titleScope is the archive_title scope of p: its week and plan revision,
+// and a fingerprint of its dinners in day order, so runs share a title only
+// when they title the same dinner names. A renamed dinner changes the
+// names but not the plan revision.
+func titleScope(p TitleJob) string {
+	names, _ := json.Marshal(p.Dinners) // a []string always encodes
+	return fmt.Sprintf("%s@%d/%x", p.WeekStart, p.Revision, sha256.Sum256(names))
+}
+
 // Get returns the Supply run of the week starting weekStart, as stored: a
 // week with none is ErrListNotFound.
 func (s *Service) Get(ctx context.Context, weekStart store.LocalDate) (l List, err error) {
@@ -264,13 +454,18 @@ func (s *Service) Get(ctx context.Context, weekStart store.LocalDate) (l List, e
 	if err != nil {
 		return List{}, fmt.Errorf("shopping: read list: %w", err)
 	}
+	return readList(ctx, q, list)
+}
+
+// readList reads the groups and items of list through q.
+func readList(ctx context.Context, q *db.Queries, list db.ShoppingList) (List, error) {
 	rows, err := q.ListShoppingGroupDinners(ctx, list.ID)
 	if err != nil {
-		return List{}, fmt.Errorf("shopping: read groups: %w", err)
+		return List{}, fmt.Errorf("shopping: read groups of %s: %w", list.WeekStart, err)
 	}
 	items, err := q.ListShoppingItems(ctx, list.ID)
 	if err != nil {
-		return List{}, fmt.Errorf("shopping: read items: %w", err)
+		return List{}, fmt.Errorf("shopping: read items of %s: %w", list.WeekStart, err)
 	}
 	byGroup := make(map[string][]Item, len(rows))
 	for _, r := range items {
@@ -365,18 +560,21 @@ type wantItem struct {
 }
 
 // wanted reads plan planID's days and their dinners' ingredients: the
-// groups the list must have, by date, and the days that get none.
-func wanted(ctx context.Context, q *db.Queries, planID string) ([]wantGroup, []SkippedDay, error) {
+// groups the list must have, by date, the days that get none, and the
+// names of the plan's dinners in day order.
+func wanted(ctx context.Context, q *db.Queries, planID string) ([]wantGroup, []SkippedDay, []string, error) {
 	days, err := q.ListPlanDays(ctx, planID)
 	if err != nil {
-		return nil, nil, fmt.Errorf("shopping: read plan days: %w", err)
+		return nil, nil, nil, fmt.Errorf("shopping: read plan days: %w", err)
 	}
 	var (
 		groups  []wantGroup
 		skipped []SkippedDay
+		names   []string
 	)
 	for _, day := range days {
 		d := day.Dinner
+		names = append(names, d.Name)
 		skip := SkippedDay{Date: day.Date, DinnerID: d.ID, DinnerName: d.Name}
 		if !d.RecipeID.Valid {
 			skip.Reason = SkipNoRecipe
@@ -385,11 +583,11 @@ func wanted(ctx context.Context, q *db.Queries, planID string) ([]wantGroup, []S
 		}
 		recipe, err := q.GetRecipe(ctx, d.RecipeID.String)
 		if err != nil {
-			return nil, nil, fmt.Errorf("shopping: read recipe %s of dinner %s: %w", d.RecipeID.String, d.ID, err)
+			return nil, nil, nil, fmt.Errorf("shopping: read recipe %s of dinner %s: %w", d.RecipeID.String, d.ID, err)
 		}
 		ings, err := q.ListRecipeIngredients(ctx, recipe.ID)
 		if err != nil {
-			return nil, nil, fmt.Errorf("shopping: read ingredients of recipe %s: %w", recipe.ID, err)
+			return nil, nil, nil, fmt.Errorf("shopping: read ingredients of recipe %s: %w", recipe.ID, err)
 		}
 		if len(ings) == 0 {
 			skip.Reason = SkipNoIngredients
@@ -401,13 +599,13 @@ func wanted(ctx context.Context, q *db.Queries, planID string) ([]wantGroup, []S
 		for _, ing := range ings {
 			it, err := item(ing, manual)
 			if err != nil {
-				return nil, nil, fmt.Errorf("shopping: recipe %s: %w", recipe.ID, err)
+				return nil, nil, nil, fmt.Errorf("shopping: recipe %s: %w", recipe.ID, err)
 			}
 			g.items = append(g.items, it)
 		}
 		groups = append(groups, g)
 	}
-	return groups, skipped, nil
+	return groups, skipped, names, nil
 }
 
 // item is the item for ingredient ing of a recipe entered by hand

internal/shopping/shopping_test.go

@@ -1,6 +1,8 @@
 package shopping_test
 
 import (
+	"bytes"
+	"context"
 	"database/sql"
 	"errors"
 	"fmt"
@@ -8,10 +10,13 @@ import (
 	"log/slog"
 	"reflect"
 	"strings"
+	"sync"
 	"testing"
+	"time"
 
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/llm"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/skills"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/dinners"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/jobs"
@@ -42,6 +47,38 @@ type env struct {
 	planID  string
 	// ids are the dinners' ids by name.
 	ids map[string]string
+	// runner runs the title jobs, two at a time, once start starts it.
+	runner *jobs.Runner
+	// model answers archive_title, which titles the Supply runs; with
+	// nothing queued it fails, and the lists stay untitled.
+	model *llm.Fake
+	// beforeTitle, when set, runs as archive_title is asked for a title.
+	beforeTitle func()
+	// afterTitle, when set, runs once archive_title has returned, before
+	// its title is stored.
+	afterTitle func()
+	// beforeModel, when set, runs as the model is sent a request.
+	beforeModel func(llm.Request)
+	// log holds what the service logged.
+	log *syncBuffer
+}
+
+// syncBuffer is a bytes.Buffer safe for concurrent use.
+type syncBuffer struct {
+	mu  sync.Mutex
+	buf bytes.Buffer
+}
+
+func (b *syncBuffer) Write(p []byte) (int, error) {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.buf.Write(p)
+}
+
+func (b *syncBuffer) String() string {
+	b.mu.Lock()
+	defer b.mu.Unlock()
+	return b.buf.String()
 }
 
 func newEnv(t *testing.T) *env {
@@ -59,11 +96,89 @@ func newEnv(t *testing.T) *env {
 	if err := store.Migrate(t.Context(), st.Writer, migrations.FS); err != nil {
 		t.Fatal(err)
 	}
-	svc, err := shopping.NewService(st)
+	e := &env{st: st, dataDir: dataDir, ids: map[string]string{}, model: &llm.Fake{}, log: &syncBuffer{}}
+	guard, err := harness.NewGuard(harness.DefaultMaxCalls)
 	if err != nil {
 		t.Fatal(err)
 	}
-	return &env{svc: svc, st: st, dataDir: dataDir, ids: map[string]string{}}
+	cfg := harness.Config{
+		Settings:    llm.Settings{Provider: "anthropic", Model: "claude-test", Temperature: 0.7},
+		NewProvider: func(llm.Settings, string) (llm.Provider, error) { return hookedModel{e}, nil },
+		Store:       st,
+		Guard:       guard,
+	}
+	title := func(ctx context.Context, scope string, in skills.ArchiveTitleRequest) (skills.ArchiveTitle, error) {
+		if e.beforeTitle != nil {
+			e.beforeTitle()
+		}
+		out, err := skills.TitleArchive(ctx, cfg, scope, in)
+		if e.afterTitle != nil {
+			e.afterTitle()
+		}
+		return out, err
+	}
+	logger := slog.New(slog.NewTextHandler(e.log, nil))
+	e.runner, err = jobs.NewRunner(st, logger, 2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	e.svc, err = shopping.NewService(st, title, e.runner, logger)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return e
+}
+
+// hookedModel is the env's model, running beforeModel first.
+type hookedModel struct{ e *env }
+
+func (m hookedModel) Generate(ctx context.Context, req llm.Request) (llm.Response, error) {
+	if m.e.beforeModel != nil {
+		m.e.beforeModel(req)
+	}
+	return m.e.model.Generate(ctx, req)
+}
+
+func (m hookedModel) ListModels(ctx context.Context) ([]llm.Model, error) {
+	return m.e.model.ListModels(ctx)
+}
+
+func (m hookedModel) Verify(ctx context.Context) error { return m.e.model.Verify(ctx) }
+
+// start starts the env's job runner, stopping it when the test ends.
+func (e *env) start(t *testing.T) {
+	t.Helper()
+	ctx, cancel := context.WithCancel(context.Background())
+	if err := e.runner.Start(ctx); err != nil {
+		cancel()
+		t.Fatal(err)
+	}
+	t.Cleanup(func() {
+		cancel()
+		e.runner.Wait()
+	})
+}
+
+// waitTitle waits for g's title job to finish and returns it.
+func (e *env) waitTitle(t *testing.T, g shopping.Generated) jobs.Job {
+	t.Helper()
+	if g.TitleJobID == nil {
+		t.Fatal("generation enqueued no title job")
+	}
+	deadline := time.Now().Add(10 * time.Second)
+	for {
+		job, err := e.runner.Get(t.Context(), *g.TitleJobID)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if job.Status == jobs.StatusSucceeded || job.Status == jobs.StatusFailed {
+			return job
+		}
+		if time.Now().After(deadline) {
+			t.Fatalf("title job %s still %s", job.ID, job.Status)
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
 }
 
 // ing is a recipe ingredient as recipe grounding stores it: an empty
@@ -349,8 +464,13 @@ func TestGenerateSevenDayPlan(t *testing.T) {
 	}
 
 	// Generating again from the same plan changes nothing: same rows, same
-	// ids, no extra rows.
+	// ids, no extra rows. The list is still untitled, so it gets another
+	// title job.
 	again := e.generate(t)
+	if again.TitleJobID == nil || g.TitleJobID == nil || *again.TitleJobID == *g.TitleJobID {
+		t.Errorf("title jobs = %v then %v, want one per generation of the untitled list", deref(g.TitleJobID), deref(again.TitleJobID))
+	}
+	again.TitleJobID = g.TitleJobID
 	if !reflect.DeepEqual(again, g) {
 		t.Errorf("second generation =\n %+v\nwant the first\n %+v", again, g)
 	}

internal/shopping/title_test.go

@@ -0,0 +1,313 @@
+package shopping_test
+
+import (
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"slices"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/harness"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/ai/llm"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/jobs"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/shopping"
+)
+
+// titled is archive_title's reply giving title.
+func titled(title string) llm.GenerateResult {
+	js := fmt.Sprintf(`{"title":%q}`, title)
+	return llm.GenerateResult{Response: llm.Response{Text: js, JSON: json.RawMessage(js)}}
+}
+
+// titleWeek stores three dinners, one with no recipe, and plans them on
+// the week's first three days; its job runner is started.
+func titleWeek(t *testing.T) *env {
+	t.Helper()
+	e := newEnv(t)
+	e.start(t)
+	e.dinner(t, "Beef Chili", ing{"ground beef", "1", "lb"})
+	e.dinner(t, "Fish Tacos")
+	e.dinner(t, "Pad Thai", ing{"rice noodles", "8", "oz"})
+	e.plan(t, "Pad Thai", "Fish Tacos", "Beef Chili")
+	return e
+}
+
+// storedTitle returns the week's list's stored title; nil when NULL.
+func (e *env) storedTitle(t *testing.T) *string {
+	t.Helper()
+	var title sql.NullString
+	if err := e.st.Reader.QueryRow(`SELECT title FROM shopping_lists WHERE week_start = ?`, week.String()).Scan(&title); err != nil {
+		t.Fatal(err)
+	}
+	if !title.Valid {
+		return nil
+	}
+	return &title.String
+}
+
+// runStatuses returns the status of every archive_title run recorded in
+// ai_runs, oldest first.
+func (e *env) runStatuses(t *testing.T) []string {
+	t.Helper()
+	rows, err := e.st.Reader.Query(`SELECT status FROM ai_runs WHERE skill = 'archive_title' ORDER BY created_at, rowid`)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer rows.Close()
+	var out []string
+	for rows.Next() {
+		var s string
+		if err := rows.Scan(&s); err != nil {
+			t.Fatal(err)
+		}
+		out = append(out, s)
+	}
+	if err := rows.Err(); err != nil {
+		t.Fatal(err)
+	}
+	return out
+}
+
+func wantTitle(t *testing.T, what string, got *string, want string) {
+	t.Helper()
+	if got == nil || *got != want {
+		t.Errorf("%s = %v, want %q", what, deref(got), want)
+	}
+}
+
+func wantUntitled(t *testing.T, what string, got *string) {
+	t.Helper()
+	if got != nil {
+		t.Errorf("%s = %q, want none", what, *got)
+	}
+}
+
+func deref(s *string) any {
+	if s == nil {
+		return nil
+	}
+	return *s
+}
+
+// wantJob fails t unless job ended with status and, when failed, code.
+func wantJob(t *testing.T, job jobs.Job, status jobs.Status, code string) {
+	t.Helper()
+	if job.Status != status || (code != "" && (job.Error == nil || *job.Error != code)) {
+		t.Errorf("title job = %s %v, want %s %s", job.Status, deref(job.Error), status, code)
+	}
+}
+
+// TestGenerateTitlesNewList: a new list is returned untitled with a title
+// job, which titles it by archive_title from the plan's dinners in day
+// order, a dinner with no group included, and stores the title.
+func TestGenerateTitlesNewList(t *testing.T) {
+	e := titleWeek(t)
+	e.model.QueueGenerate(titled("Noodles, Tacos and Chili"))
+
+	g := e.generate(t)
+	wantUntitled(t, "returned title", g.List.Title)
+	job := e.waitTitle(t, g)
+
+	wantJob(t, job, jobs.StatusSucceeded, "")
+	if want := `{"list_id":"` + g.List.ID + `","title":"Noodles, Tacos and Chili"}`; string(job.Result) != want {
+		t.Errorf("job result = %s, want %s", job.Result, want)
+	}
+	wantTitle(t, "stored title", e.storedTitle(t), "Noodles, Tacos and Chili")
+	got, err := e.svc.Get(t.Context(), week)
+	if err != nil {
+		t.Fatal(err)
+	}
+	wantTitle(t, "title read back", got.Title, "Noodles, Tacos and Chili")
+	reqs := e.model.Requests()
+	if len(reqs) != 1 {
+		t.Fatalf("%d model calls, want 1", len(reqs))
+	}
+	want := "Title the week whose dinners are, in day order from Monday:\n- Pad Thai\n- Fish Tacos\n- Beef Chili"
+	if user := reqs[0].Messages[0].Content; user != want {
+		t.Errorf("user message = %q, want %q", user, want)
+	}
+	if s := e.runStatuses(t); len(s) != 1 || s[0] != string(harness.StatusOK) {
+		t.Errorf("archive_title runs = %q, want one ok", s)
+	}
+}
+
+// TestGenerateTitleTooLongRepaired: a title over 48 characters is repaired
+// through the repair turn, and the repaired title is stored, not a
+// truncation of the first.
+func TestGenerateTitleTooLongRepaired(t *testing.T) {
+	e := titleWeek(t)
+	long := "Pad Thai Monday, Fish Taco Tuesday and Chili Wednesday"
+	e.model.QueueGenerate(titled(long), titled("Noodles, Tacos and Chili"))
+
+	wantJob(t, e.waitTitle(t, e.generate(t)), jobs.StatusSucceeded, "")
+
+	wantTitle(t, "stored title", e.storedTitle(t), "Noodles, Tacos and Chili")
+	reqs := e.model.Requests()
+	if len(reqs) != 2 || !strings.Contains(reqs[1].Messages[2].Content, "has 54 characters; shorten it to at most 48") {
+		t.Fatalf("model calls = %+v, want a repair turn asking for a shorter title", reqs)
+	}
+	if s := e.runStatuses(t); len(s) != 1 || s[0] != string(harness.StatusRepaired) {
+		t.Errorf("archive_title runs = %q, want one repaired", s)
+	}
+}
+
+// TestGenerateTitleFailureKeepsList: archive_title giving an emoji twice
+// fails, and the list is still made, whole and untitled, with the failure
+// logged, recorded in ai_runs and failing the title job.
+func TestGenerateTitleFailureKeepsList(t *testing.T) {
+	e := titleWeek(t)
+	e.model.QueueGenerate(titled("Taco Week 🌮"), titled("Taco Week 🌮"))
+
+	g, err := e.svc.Generate(t.Context(), week)
+	if err != nil {
+		t.Fatalf("Generate = %v, want the list made though its title failed", err)
+	}
+
+	want := []string{
+		"0 2026-10-12 Pad Thai: 0 rice noodles [8 oz] needed",
+		"1 2026-10-14 Beef Chili: 0 ground beef [1 lb] needed",
+	}
+	wantLines(t, "list", lines(g.List), want)
+	wantLines(t, "stored list", e.stored(t), want)
+	if len(g.Skipped) != 1 || g.Skipped[0].DinnerName != "Fish Tacos" {
+		t.Errorf("skipped = %+v, want Fish Tacos", g.Skipped)
+	}
+	wantJob(t, e.waitTitle(t, g), jobs.StatusFailed, shopping.ReasonTitleFailed)
+	wantUntitled(t, "returned title", g.List.Title)
+	wantUntitled(t, "stored title", e.storedTitle(t))
+	if g.List.Status != shopping.StatusCurrent {
+		t.Errorf("status = %q, want current", g.List.Status)
+	}
+	log := e.log.String()
+	for _, part := range []string{"level=WARN", "Supply run left untitled", "week=2026-10-12", "has an emoji (U+1F32E)"} {
+		if !strings.Contains(log, part) {
+			t.Errorf("log lacks %q:\n%s", part, log)
+		}
+	}
+	if s := e.runStatuses(t); len(s) != 1 || s[0] != string(harness.StatusBadOutput) {
+		t.Errorf("archive_title runs = %q, want one bad_output", s)
+	}
+}
+
+// TestGenerateRetriesTitle: a list left untitled is titled by the week's
+// next generation, Generate or GeneratePushed; once titled, a remake keeps
+// its title and asks for none.
+func TestGenerateRetriesTitle(t *testing.T) {
+	e := titleWeek(t)
+	e.model.QueueGenerate(llm.GenerateResult{Err: fmt.Errorf("%w: model down", llm.ErrProvider)})
+	first := e.generate(t)
+	wantJob(t, e.waitTitle(t, first), jobs.StatusFailed, shopping.ReasonTitleFailed)
+	wantUntitled(t, "first title", e.storedTitle(t))
+	if !strings.Contains(e.log.String(), "model down") {
+		t.Errorf("log lacks the failure:\n%s", e.log.String())
+	}
+
+	e.model.QueueGenerate(titled("Noodles, Tacos and Chili"))
+	plan, err := db.New(e.st.Reader).GetWeekPlan(t.Context(), week.String())
+	if err != nil {
+		t.Fatal(err)
+	}
+	second, err := e.svc.GeneratePushed(t.Context(), week, plan.Revision)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if second.List.ID != first.List.ID {
+		t.Fatalf("second generation made list %s, want list %s again", second.List.ID, first.List.ID)
+	}
+	wantJob(t, e.waitTitle(t, second), jobs.StatusSucceeded, "")
+	wantTitle(t, "retried title", e.storedTitle(t), "Noodles, Tacos and Chili")
+
+	e.swap(t, "2026-10-12", "Beef Chili")
+	third := e.generate(t)
+	wantTitle(t, "title after a remake", third.List.Title, "Noodles, Tacos and Chili")
+	if third.TitleJobID != nil {
+		t.Errorf("a remake of a titled list enqueued title job %s", *third.TitleJobID)
+	}
+	if n := len(e.model.Requests()); n != 2 {
+		t.Errorf("%d model calls, want 2: a titled list is not titled again", n)
+	}
+}
+
+// TestGenerateTitleNotStoredOnFrozenList: a list frozen into the Supply
+// archive while its title is written keeps no title, and the failure is
+// logged.
+func TestGenerateTitleNotStoredOnFrozenList(t *testing.T) {
+	e := titleWeek(t)
+	e.model.QueueGenerate(titled("Noodles, Tacos and Chili"))
+	e.beforeTitle = func() {
+		if _, err := e.st.Writer.Exec(`UPDATE shopping_lists SET status = 'archived', frozen_at = '2026-10-19T04:05:00Z'`); err != nil {
+			t.Error(err)
+		}
+	}
+
+	wantJob(t, e.waitTitle(t, e.generate(t)), jobs.StatusFailed, shopping.ReasonTitleFailed)
+
+	wantUntitled(t, "stored title", e.storedTitle(t))
+	if !strings.Contains(e.log.String(), "the Supply run was frozen or replaced before its title was stored") {
+		t.Errorf("log lacks the failure:\n%s", e.log.String())
+	}
+}
+
+// TestGenerateTitleOverlapAcrossRename: a dinner renamed between two
+// generations of an untitled list changes the names to title but not the
+// plan revision. The two title jobs, running at once, each send the model
+// their own names; neither is given the other's title.
+func TestGenerateTitleOverlapAcrossRename(t *testing.T) {
+	e := titleWeek(t)
+	e.model.QueueGenerate(titled("Noodles, Tacos and Chili"), titled("Drunken Noodles Week"))
+	// Each model call waits for the other, so the runs overlap.
+	var arrived sync.WaitGroup
+	arrived.Add(2)
+	e.beforeModel = func(llm.Request) {
+		arrived.Done()
+		done := make(chan struct{})
+		go func() { arrived.Wait(); close(done) }()
+		select {
+		case <-done:
+		case <-time.After(5 * time.Second):
+			t.Error("the title runs did not overlap: one model call never came")
+		}
+	}
+	revision := func() int64 {
+		p, err := db.New(e.st.Reader).GetWeekPlan(t.Context(), week.String())
+		if err != nil {
+			t.Fatal(err)
+		}
+		return p.Revision
+	}
+
+	before := revision()
+	first := e.generate(t)
+	if _, err := e.st.Writer.Exec(`UPDATE dinners SET name = 'Drunken Noodles', normalized_name = 'drunken noodles' WHERE id = ?`, e.ids["Pad Thai"]); err != nil {
+		t.Fatal(err)
+	}
+	second := e.generate(t)
+	if revision() != before {
+		t.Fatalf("plan revision moved from %d to %d: the rename must leave it", before, revision())
+	}
+
+	wantJob(t, e.waitTitle(t, first), jobs.StatusSucceeded, "")
+	wantJob(t, e.waitTitle(t, second), jobs.StatusSucceeded, "")
+	var users []string
+	for _, r := range e.model.Requests() {
+		users = append(users, r.Messages[0].Content)
+	}
+	slices.Sort(users)
+	want := []string{
+		"Title the week whose dinners are, in day order from Monday:\n- Drunken Noodles\n- Fish Tacos\n- Beef Chili",
+		"Title the week whose dinners are, in day order from Monday:\n- Pad Thai\n- Fish Tacos\n- Beef Chili",
+	}
+	if !slices.Equal(users, want) {
+		t.Errorf("model was sent %q, want each generation's own names %q", users, want)
+	}
+	if s := e.runStatuses(t); len(s) != 2 {
+		t.Errorf("archive_title runs = %q, want two", s)
+	}
+	if got := e.storedTitle(t); got == nil || (*got != "Noodles, Tacos and Chili" && *got != "Drunken Noodles Week") {
+		t.Errorf("stored title = %v, want one of the two titles", deref(got))
+	}
+}

migrations/queries/shopping.sql

@@ -81,3 +81,24 @@ WHERE shopping_items.id = ?;
 UPDATE shopping_items
 SET needed = ?, updated_at = ?
 WHERE id = ?;
+
+-- name: SetShoppingListTitle :execrows
+-- Titles list id, unless it has a title already or is frozen into the
+-- Supply archive.
+UPDATE shopping_lists
+SET title = ?, updated_at = ?
+WHERE id = ? AND title IS NULL AND status = 'current' AND frozen_at IS NULL;
+
+-- name: FreezeShoppingList :execrows
+-- Freezes list id into the Supply archive at frozen_at, unless it is
+-- frozen already.
+UPDATE shopping_lists
+SET status = 'archived', frozen_at = ?, updated_at = ?
+WHERE id = ? AND frozen_at IS NULL;
+
+-- name: ListShoppingListsThrough :many
+-- The Supply runs of the weeks starting on or before week_start, newest
+-- week first.
+SELECT * FROM shopping_lists
+WHERE week_start <= ?
+ORDER BY week_start DESC;