diff --git a/frontend/src/api/moments.ts b/frontend/src/api/moments.ts
new file mode 100644
index 00000000..9a8f8581
--- /dev/null
+++ b/frontend/src/api/moments.ts
@@ -0,0 +1,101 @@
+import { apiGet, apiPost, apiDelete } from "@/api/client";
+
+/**
+ * The moments of work rules mount on (milestone 458), and the actions that
+ * reach each one on this install — `GET /api/retrieval/moments`, the payload
+ * the `list_moments` MCP tool returns, plus the counts the Settings view shows
+ * beside each moment.
+ */
+export interface Moment {
+  name: string;
+  /** What is happening at this moment. */
+  means: string;
+  /** The kinds of action that typically reach it. */
+  reached_by: string;
+}
+
+/** A shape rather than an entry: `skill.<name>`, one moment per procedure. */
+export interface MomentFamily {
+  name: string;
+  prefix: string;
+  means: string;
+  reached_by: string;
+}
+
+/** `default` ships with the product; `install` is this install's own. */
+export type ActionVia = "default" | "install";
+
+export interface MomentAction {
+  tool: string;
+  /** Empty = every call of the tool. A command prefix for a command tool,
+   *  `field=value` pairs for any other. */
+  match: string;
+  via: ActionVia;
+}
+
+/** A shipped default this install switched off. */
+export interface RemovedDefault {
+  id: number;
+  tool: string;
+  match: string;
+  moment: string;
+  reason: string | null;
+  actor: string | null;
+  created_at: string | null;
+}
+
+export interface MomentUsage {
+  /** How many times a mounted rule arrived at this moment. */
+  delivered: number;
+  /** How many distinct rules did. */
+  rules: number;
+  /** Of those, how many an agent then opened — an upper bound: a pull records
+   *  the door, not the line that prompted it. */
+  opened: number;
+  last_delivered_at: string | null;
+}
+
+export interface MomentsPayload {
+  moments: Moment[];
+  families: MomentFamily[];
+  total: number;
+  actions: Record<string, MomentAction[]>;
+  removed_defaults: RemovedDefault[];
+  /** Rules mounted per moment; a moment carrying none is absent. */
+  mounted: Record<string, number>;
+  /** The count read failed — `mounted` is empty for that reason, not because
+   *  nothing is mounted. */
+  mounted_failed?: boolean;
+  usage: {
+    by_moment: Record<string, MomentUsage>;
+    days: number;
+    /** Same distinction as `mounted_failed`, for the usage read. */
+    moment_usage_failed?: boolean;
+  };
+}
+
+export interface MappingChange {
+  tool: string;
+  match?: string;
+  moment: string;
+  reason?: string;
+}
+
+export function getMoments(days = 30): Promise<MomentsPayload> {
+  return apiGet(`/api/retrieval/moments?days=${days}`);
+}
+
+export function mapAction(change: MappingChange): Promise<unknown> {
+  return apiPost("/api/retrieval/moments/mappings", change);
+}
+
+/** Query parameters, not a body: DELETE bodies are not reliably sent. */
+export function unmapAction(change: MappingChange): Promise<void> {
+  const q = new URLSearchParams({
+    tool: change.tool,
+    match: change.match ?? "",
+    moment: change.moment,
+    reason: change.reason ?? "",
+  });
+  return apiDelete(`/api/retrieval/moments/mappings?${q.toString()}`);
+}
diff --git a/frontend/src/api/rulebooks.ts b/frontend/src/api/rulebooks.ts
index 16c3c25b..e84f10c0 100644
--- a/frontend/src/api/rulebooks.ts
+++ b/frontend/src/api/rulebooks.ts
@@ -82,6 +82,9 @@ export interface Rule {
   updated_at: string | null;
   /** Present only when the rule has them (the server omits empty keys). */
   systems?: { id: number; name: string }[];
+  /** The moments this rule arrives at whenever they happen (milestone 458),
+   *  in catalog order. Present only when the rule is mounted. */
+  moments?: string[];
   relations?: RuleRelation[];
   /** The lessons that point at this rule (milestone 440) — the concrete
    *  situations judged instances of it, plus any suggested and awaiting a
@@ -210,6 +213,8 @@ export interface RuleWrite {
   how_to_apply: string;
   order_index: number;
   system_ids: number[];
+  /** Replaces the set; [] unmounts the rule from every moment. */
+  moments: string[];
   arose_from_id: number | null;
   verify_with: string;
   expires_when: string;
diff --git a/frontend/src/assets/moments-shared.css b/frontend/src/assets/moments-shared.css
new file mode 100644
index 00000000..0bb072f0
--- /dev/null
+++ b/frontend/src/assets/moments-shared.css
@@ -0,0 +1,26 @@
+/* Moments (milestone 458): the pieces the rule editor's picker and the
+   Settings section share, so a moment's name and a chip's remove control look
+   the same wherever a person meets them. Loaded unscoped by both. */
+
+/* The name as a session reads it in a delivered line — shown as written. */
+.moment-name {
+  font-family: var(--fs-font-mono);
+  color: var(--fs-text-primary);
+}
+
+/* The × on a removable chip: quiet until hovered, and keyboard-reachable. */
+.chip-remove {
+  background: none;
+  border: none;
+  cursor: pointer;
+  padding: 0;
+  font: inherit;
+  color: var(--fs-text-tertiary);
+}
+.chip-remove:hover:not(:disabled) { color: var(--fs-text-primary); }
+.chip-remove:disabled { opacity: var(--fs-disabled-opacity); cursor: default; }
+.chip-remove:focus-visible {
+  outline: none;
+  box-shadow: var(--fs-focus-ring);
+  border-radius: var(--fs-radius-sm);
+}
diff --git a/frontend/src/components/MomentsSettings.vue b/frontend/src/components/MomentsSettings.vue
new file mode 100644
index 00000000..b2a07a67
--- /dev/null
+++ b/frontend/src/components/MomentsSettings.vue
@@ -0,0 +1,294 @@
+<script setup lang="ts">
+import { computed, onMounted, ref } from "vue";
+import { useMomentsStore } from "@/stores/moments";
+import type { MomentAction, MomentUsage } from "@/api/moments";
+import { fmtDate } from "@/utils/dateFormat";
+
+/**
+ * The human door onto moments (milestone 458 step 6): every moment in the
+ * catalog, the actions that reach it on this install, how many rules ride on
+ * it, and what reaching it has delivered. The session's own door is
+ * `list_moments` / `map_action` / `unmap_action`, and both call the same
+ * services — this view exists so a person can see and change everything an
+ * agent can, without asking one to.
+ */
+const store = useMomentsStore();
+
+const data = computed(() => store.data);
+const catalog = computed(() => data.value?.moments ?? []);
+const days = computed(() => data.value?.usage.days ?? 30);
+const usageFailed = computed(() => !!data.value?.usage.moment_usage_failed);
+
+function actionsFor(moment: string): MomentAction[] {
+  return data.value?.actions[moment] ?? [];
+}
+function mounted(moment: string): number {
+  return data.value?.mounted[moment] ?? 0;
+}
+function usage(moment: string): MomentUsage | null {
+  return data.value?.usage.by_moment[moment] ?? null;
+}
+
+// A named procedure is its own moment (`skill.<name>`), so it appears here
+// only once something is mounted on it or has been delivered at it — the
+// catalog cannot list procedures it has never heard of.
+const procedureMoments = computed(() => {
+  const names = new Set<string>([
+    ...Object.keys(data.value?.mounted ?? {}),
+    ...Object.keys(data.value?.usage.by_moment ?? {}),
+  ]);
+  return [...names].filter((n) => n.startsWith("skill.")).sort();
+});
+
+function actionLabel(a: { tool: string; match: string }): string {
+  return a.match ? `${a.tool} · ${a.match}` : a.tool;
+}
+
+const busy = ref(false);
+
+async function run(fn: () => Promise<unknown>) {
+  busy.value = true;
+  try {
+    await fn();
+  } catch {
+    // The store has already said why; the row stays as it was.
+  } finally {
+    busy.value = false;
+  }
+}
+
+function removeAction(moment: string, a: MomentAction) {
+  // A shipped default is switched off rather than deleted, and comes back
+  // with "Restore" below — worth a confirm, since every later session on
+  // this install loses the moment for that action.
+  if (a.via === "default"
+      && !confirm(`Stop ${actionLabel(a)} reaching ${moment} on this install? You can restore it below.`)) {
+    return;
+  }
+  void run(() => store.unmap({ tool: a.tool, match: a.match, moment, reason: "Removed in Settings." }));
+}
+
+function restore(r: { tool: string; match: string; moment: string }) {
+  void run(() => store.map({ tool: r.tool, match: r.match, moment: r.moment }));
+}
+
+// ── Add a mapping ─────────────────────────────────────────────────────────
+const draftTool = ref("");
+const draftMatch = ref("");
+const draftMoment = ref("");
+const draftReason = ref("");
+const canAdd = computed(() => !!draftTool.value.trim() && !!draftMoment.value && !busy.value);
+
+async function addMapping() {
+  if (!canAdd.value) return;
+  busy.value = true;
+  try {
+    await store.map({
+      tool: draftTool.value.trim(),
+      match: draftMatch.value.trim(),
+      moment: draftMoment.value,
+      reason: draftReason.value.trim(),
+    });
+    draftTool.value = "";
+    draftMatch.value = "";
+    draftReason.value = "";
+  } catch {
+    // Kept as typed, so the refusal the store showed can be acted on.
+  } finally {
+    busy.value = false;
+  }
+}
+
+onMounted(() => store.fetch(true));
+</script>
+
+<template>
+  <div class="moments-settings">
+    <p v-if="store.loading && !data" class="empty-msg">Loading moments…</p>
+    <p v-else-if="store.failed && !data" class="error-msg">
+      The moment catalog could not be loaded.
+      <button type="button" class="btn-text" @click="store.fetch(true)">Try again</button>
+    </p>
+
+    <template v-else-if="data">
+      <p class="window-note">
+        Deliveries and opens over the last {{ days }} days. “Opened” counts the rules an agent
+        went on to read — an upper bound, since a rule delivered at two moments and read once
+        counts at both.
+      </p>
+      <p v-if="usageFailed" class="error-msg">
+        The delivery counts could not be read, so they are missing below — not zero.
+      </p>
+      <p v-if="data.mounted_failed" class="error-msg">
+        The mount counts could not be read, so they are missing below — not zero.
+      </p>
+
+      <ul class="moment-list">
+        <li v-for="m in catalog" :key="m.name" class="moment-row">
+          <div class="moment-head">
+            <code class="moment-name">{{ m.name }}</code>
+            <span class="moment-stats">
+              <span :class="{ 'stat-none': !mounted(m.name) }">
+                {{ mounted(m.name) ? `${mounted(m.name)} ${mounted(m.name) === 1 ? "rule" : "rules"} mounted` : "nothing mounted" }}
+              </span>
+              <template v-if="usage(m.name)">
+                <span>delivered {{ usage(m.name)!.delivered }}</span>
+                <span>opened {{ usage(m.name)!.opened }} of {{ usage(m.name)!.rules }}</span>
+                <span v-if="usage(m.name)!.last_delivered_at" class="stat-when">
+                  last {{ fmtDate(usage(m.name)!.last_delivered_at!) }}
+                </span>
+              </template>
+            </span>
+          </div>
+          <p class="moment-desc">{{ m.means }}</p>
+          <div class="moment-actions">
+            <span class="actions-label">Reached by</span>
+            <span v-if="!actionsFor(m.name).length" class="stat-none">
+              no action here — {{ m.reached_by }}
+            </span>
+            <span
+              v-for="a in actionsFor(m.name)"
+              :key="`${a.via}:${a.tool}:${a.match}`"
+              :class="['action-chip', { 'is-install': a.via === 'install' }]"
+              :title="a.via === 'install' ? 'Added on this install' : 'Ships with Scribe'"
+            >
+              <code>{{ actionLabel(a) }}</code>
+              <button
+                type="button"
+                class="chip-remove"
+                :disabled="busy"
+                :aria-label="a.via === 'install'
+                  ? `Remove ${actionLabel(a)} from ${m.name}`
+                  : `Switch off the shipped ${actionLabel(a)} for ${m.name}`"
+                @click="removeAction(m.name, a)"
+              >×</button>
+            </span>
+          </div>
+        </li>
+      </ul>
+
+      <template v-if="procedureMoments.length">
+        <h3 class="sub-title">Named procedures</h3>
+        <ul class="moment-list">
+          <li v-for="name in procedureMoments" :key="name" class="moment-row">
+            <div class="moment-head">
+              <code class="moment-name">{{ name }}</code>
+              <span class="moment-stats">
+                <span :class="{ 'stat-none': !mounted(name) }">
+                  {{ mounted(name) ? `${mounted(name)} ${mounted(name) === 1 ? "rule" : "rules"} mounted` : "nothing mounted" }}
+                </span>
+                <template v-if="usage(name)">
+                  <span>delivered {{ usage(name)!.delivered }}</span>
+                  <span>opened {{ usage(name)!.opened }} of {{ usage(name)!.rules }}</span>
+                </template>
+              </span>
+            </div>
+          </li>
+        </ul>
+      </template>
+
+      <template v-if="data.removed_defaults.length">
+        <h3 class="sub-title">Shipped mappings switched off here</h3>
+        <ul class="removed-list">
+          <li v-for="r in data.removed_defaults" :key="r.id" class="removed-row">
+            <code>{{ actionLabel(r) }}</code>
+            <span class="removed-arrow">→</span>
+            <code>{{ r.moment }}</code>
+            <span v-if="r.reason" class="removed-reason">{{ r.reason }}</span>
+            <button type="button" class="btn-text" :disabled="busy" @click="restore(r)">Restore</button>
+          </li>
+        </ul>
+      </template>
+
+      <form class="add-mapping" @submit.prevent="addMapping">
+        <h3 class="sub-title">Add an action</h3>
+        <p class="field-hint">
+          When something you do plainly happens at a moment and nothing fired — your own deploy
+          script, a tool from another MCP server. For a command tool, the match is how the command
+          starts (<code>make ship</code>); for any other tool, its arguments as
+          <code>field=value</code> pairs. Leave it empty to map every call.
+        </p>
+        <div class="add-grid">
+          <label>
+            Tool
+            <input v-model="draftTool" class="fs-input" placeholder="Bash, or an MCP tool's name" />
+          </label>
+          <label>
+            Match
+            <input v-model="draftMatch" class="fs-input" placeholder="make ship · status=done · empty for every call" />
+          </label>
+          <label>
+            Moment
+            <select v-model="draftMoment" class="fs-input">
+              <option value="" disabled>Choose a moment</option>
+              <option v-for="m in catalog" :key="m.name" :value="m.name">{{ m.name }}</option>
+            </select>
+          </label>
+          <label>
+            Why <span class="optional">(optional)</span>
+            <input v-model="draftReason" class="fs-input" placeholder="what it is for here" />
+          </label>
+        </div>
+        <button type="submit" class="btn-primary" :disabled="!canAdd">Add action</button>
+      </form>
+    </template>
+  </div>
+</template>
+
+<style scoped>
+.moments-settings { display: flex; flex-direction: column; gap: var(--fs-space-3); }
+.window-note { margin: 0; font-size: var(--fs-size-tiny); color: var(--fs-text-tertiary); line-height: var(--fs-leading-body); }
+
+.moment-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: var(--fs-space-2); }
+.moment-row {
+  padding: var(--fs-space-3);
+  background: var(--fs-surface-page);
+  border: 1px solid var(--fs-border-color);
+  border-radius: var(--fs-radius-md);
+}
+.moment-head { display: flex; align-items: baseline; flex-wrap: wrap; gap: var(--fs-space-2); }
+.moment-head .moment-name { font-size: var(--fs-size-body-sm); }
+.moment-stats {
+  margin-left: auto;
+  display: flex; flex-wrap: wrap; gap: var(--fs-space-3);
+  font-size: var(--fs-size-tiny); color: var(--fs-text-secondary);
+  font-variant-numeric: tabular-nums;
+}
+/* Nothing mounted is the ordinary state of most moments, not a fault. */
+.stat-none { color: var(--fs-text-tertiary); font-style: italic; }
+.stat-when { color: var(--fs-text-tertiary); }
+.moment-desc { margin: var(--fs-space-1) 0 var(--fs-space-2); font-size: var(--fs-size-body-sm); color: var(--fs-text-secondary); line-height: var(--fs-leading-body); }
+
+.moment-actions { display: flex; flex-wrap: wrap; align-items: center; gap: var(--fs-space-2); font-size: var(--fs-size-tiny); }
+.actions-label { color: var(--fs-text-tertiary); text-transform: uppercase; letter-spacing: var(--fs-tracking-tiny); }
+.action-chip {
+  display: inline-flex; align-items: center; gap: var(--fs-space-1);
+  padding: 0.05rem 0.45rem;
+  border: 1px solid var(--fs-border-color);
+  border-radius: var(--fs-radius-sm);
+  color: var(--fs-text-secondary);
+}
+.action-chip code { font-family: var(--fs-font-mono); }
+/* This install's own, set apart from the shipped ones the way the tuning
+   trail marks the operator's changes: a dashed edge, no accent. */
+.action-chip.is-install { border-style: dashed; color: var(--fs-text-primary); }
+
+.sub-title { margin: var(--fs-space-3) 0 var(--fs-space-1); font-size: 0.95rem; color: var(--fs-text-primary); }
+
+.removed-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: var(--fs-space-1); }
+.removed-row { display: flex; flex-wrap: wrap; align-items: baseline; gap: var(--fs-space-2); font-size: var(--fs-size-body-sm); }
+.removed-row code { font-family: var(--fs-font-mono); color: var(--fs-text-secondary); text-decoration: line-through; }
+.removed-arrow { color: var(--fs-text-tertiary); }
+.removed-reason { color: var(--fs-text-tertiary); font-size: var(--fs-size-tiny); }
+
+.add-mapping { display: flex; flex-direction: column; gap: var(--fs-space-2); align-items: flex-start; }
+.add-grid {
+  width: 100%;
+  display: grid; grid-template-columns: repeat(auto-fit, minmax(12rem, 1fr));
+  gap: var(--fs-space-2) var(--fs-space-3);
+}
+.add-grid label { display: flex; flex-direction: column; gap: var(--fs-space-1); font-size: var(--fs-size-body-sm); color: var(--fs-text-primary); }
+.optional { color: var(--fs-text-tertiary); font-weight: normal; }
+</style>
+
+<style src="@/assets/moments-shared.css" />
diff --git a/frontend/src/components/rules/RuleEditorSlideOver.vue b/frontend/src/components/rules/RuleEditorSlideOver.vue
index d33b7f97..b1450a7f 100644
--- a/frontend/src/components/rules/RuleEditorSlideOver.vue
+++ b/frontend/src/components/rules/RuleEditorSlideOver.vue
@@ -2,6 +2,7 @@
 import { computed, ref, watch, onMounted } from "vue";
 import { useRulebooksStore } from "@/stores/rulebooks";
 import { useCanonicalSystemsStore } from "@/stores/canonicalSystems";
+import { useMomentsStore } from "@/stores/moments";
 import RuleHistoryPanel from "@/components/rules/RuleHistoryPanel.vue";
 import RuleHomePicker from "@/components/rules/RuleHomePicker.vue";
 import type { Rule, RuleKind } from "@/api/rulebooks";
@@ -11,6 +12,7 @@ const emit = defineEmits<{ close: [] }>();
 
 const store = useRulebooksStore();
 const canon = useCanonicalSystemsStore();
+const momentsStore = useMomentsStore();
 const title = ref("");
 const statement = ref("");
 const whenToApply = ref("");
@@ -20,6 +22,18 @@ const whenToApply = ref("");
 // session may quietly rewrite.
 const kind = ref<RuleKind>("rule");
 const systemIds = ref<number[]>([]);
+// The moments this rule is mounted on (milestone 458). Catalog moments are
+// ticked; a named procedure's moment (`skill.<name>`) is typed, since its
+// name is the procedure's own and no list here could know it.
+const ruleMoments = ref<string[]>([]);
+const procedureDraft = ref("");
+const procedureError = ref("");
+const SKILL_PREFIX = "skill.";
+const SKILL_NAME = /^[a-z0-9][a-z0-9_:-]*$/;
+const momentCatalog = computed(() => momentsStore.data?.moments ?? []);
+const procedureMoments = computed(() =>
+  ruleMoments.value.filter((m) => m.startsWith(SKILL_PREFIX)),
+);
 const why = ref("");
 const howToApply = ref("");
 const verifyWith = ref("");
@@ -46,6 +60,26 @@ function relationLabel(kind: string, direction: "outgoing" | "incoming") {
   return RELATION_LABEL[kind]?.[direction] ?? kind;
 }
 
+function toggleMoment(name: string) {
+  const at = ruleMoments.value.indexOf(name);
+  if (at >= 0) ruleMoments.value.splice(at, 1);
+  else ruleMoments.value.push(name);
+}
+
+// The same check the server makes (services/moments.is_moment), so a typo is
+// caught at the field rather than as a failed save.
+function addProcedureMoment() {
+  const raw = procedureDraft.value.trim().toLowerCase();
+  const name = raw.startsWith(SKILL_PREFIX) ? raw : SKILL_PREFIX + raw;
+  if (!SKILL_NAME.test(name.slice(SKILL_PREFIX.length))) {
+    procedureError.value = "A procedure name is lowercase letters, digits, - _ and :, with no spaces.";
+    return;
+  }
+  procedureError.value = "";
+  if (!ruleMoments.value.includes(name)) ruleMoments.value.push(name);
+  procedureDraft.value = "";
+}
+
 function toggleSystem(id: number) {
   const at = systemIds.value.indexOf(id);
   if (at >= 0) systemIds.value.splice(at, 1);
@@ -85,6 +119,7 @@ async function load() {
       whenToApply.value = r.when_to_apply || "";
       kind.value = r.kind;
       systemIds.value = (r.systems ?? []).map((sys) => sys.id);
+      ruleMoments.value = [...(r.moments ?? [])];
       why.value = r.why || "";
       howToApply.value = r.how_to_apply || "";
       verifyWith.value = r.verify_with || "";
@@ -96,12 +131,15 @@ async function load() {
     whenToApply.value = "";
     kind.value = "rule";
     systemIds.value = [];
+    ruleMoments.value = [];
     why.value = "";
     howToApply.value = "";
     verifyWith.value = "";
     expiresWhen.value = "";
   }
-  await canon.fetchCatalog();
+  procedureDraft.value = "";
+  procedureError.value = "";
+  await Promise.all([canon.fetchCatalog(), momentsStore.fetch()]);
 }
 
 async function save() {
@@ -117,6 +155,9 @@ async function save() {
     // Always sent, so clearing the last area actually clears it — the server
     // reads a list as "these ARE the areas now".
     system_ids: systemIds.value,
+    // Always sent, for system_ids' reason: the server reads the list as the
+    // whole set, so unticking the last moment actually unmounts the rule.
+    moments: ruleMoments.value,
     why: why.value,
     how_to_apply: howToApply.value,
     // Always sent, including empty. The REST door maps "" to NULL, so
@@ -210,6 +251,54 @@ watch(() => props.ruleId, load);
         its trigger, so an empty trigger leaves the rule findable by nobody.
       </p>
 
+      <fieldset v-if="momentCatalog.length" class="moments">
+        <legend>Moments it arrives at</legend>
+        <p class="field-note intro">
+          Whenever one of these happens, this rule is delivered — whatever the
+          words of the work look like. Use it for a rule about <em>when</em>
+          something is done rather than what it is about: a rule on when work
+          counts as finished belongs where work is finished and reported, and
+          nothing said there needs to resemble it.
+        </p>
+        <label v-for="m in momentCatalog" :key="m.name" class="area-opt">
+          <input
+            type="checkbox"
+            :checked="ruleMoments.includes(m.name)"
+            @change="toggleMoment(m.name)"
+          />
+          <span>
+            <code class="moment-name">{{ m.name }}</code>
+            <span class="moment-means">{{ m.means }}</span>
+          </span>
+        </label>
+        <div v-if="procedureMoments.length" class="procedure-moments">
+          <span v-for="m in procedureMoments" :key="m" class="rule-chip procedure-chip">
+            <code>{{ m }}</code>
+            <button
+              type="button"
+              class="chip-remove"
+              :aria-label="`Unmount from ${m}`"
+              @click="toggleMoment(m)"
+            >×</button>
+          </span>
+        </div>
+        <div class="procedure-add">
+          <input
+            v-model="procedureDraft"
+            aria-label="A named procedure this rule arrives with"
+            placeholder="skill.release-notes — when a named procedure is loaded"
+            @keydown.enter.prevent="addProcedureMoment"
+          />
+          <button
+            type="button"
+            class="btn-secondary btn-sm"
+            :disabled="!procedureDraft.trim()"
+            @click="addProcedureMoment"
+          >Add</button>
+        </div>
+        <p v-if="procedureError" class="trigger-warning">{{ procedureError }}</p>
+      </fieldset>
+
       <fieldset v-if="canon.catalog.length" class="areas">
         <legend>Areas this rule is about</legend>
         <label v-for="entry in canon.catalog" :key="entry.id" class="area-opt">
@@ -370,6 +459,17 @@ legend { padding: 0 0.35rem; font-size: 0.8rem; color: var(--fs-text-tertiary);
 .area-opt { display: flex; align-items: flex-start; gap: 0.5rem; margin-bottom: 0.4rem; font-size: 0.88rem; }
 .area-opt input { width: auto; margin-top: 0.2rem; accent-color: var(--fs-accent); }
 .trigger-missing textarea { border-color: var(--fs-warning); }
+/* The moment picker (milestone 458): the name is what a session reads in a
+   delivered line, so it is shown as written; the meaning is the gloss. */
+.moments { margin-bottom: 1rem; }
+.moments .intro { margin-top: 0; margin-bottom: var(--fs-space-3); }
+.moments .moment-name { font-size: var(--fs-size-tiny); }
+.moment-means { display: block; font-size: var(--fs-size-tiny); color: var(--fs-text-tertiary); line-height: var(--fs-leading-body); }
+.procedure-moments { display: flex; flex-wrap: wrap; gap: var(--fs-space-2); margin: var(--fs-space-2) 0; }
+.procedure-chip { display: inline-flex; align-items: center; gap: var(--fs-space-1); }
+.procedure-add { display: flex; gap: var(--fs-space-2); align-items: center; margin-top: var(--fs-space-2); }
+.procedure-add input { margin-top: 0; }
+.procedure-add .btn-sm { flex: none; }
 /* --fs-warning-fg, not --fs-warning: the token set draws the distinction
    between the warning HUE and warning text, and this is text. */
 .trigger-warning {
@@ -422,3 +522,4 @@ legend { padding: 0 0.35rem; font-size: 0.8rem; color: var(--fs-text-tertiary);
      panes already use, loaded here because the slide-over can open with no
      pane that loads it (a link straight to ?rule=N). -->
 <style src="@/assets/rules-shared.css" />
+<style src="@/assets/moments-shared.css" />
diff --git a/frontend/src/stores/moments.ts b/frontend/src/stores/moments.ts
new file mode 100644
index 00000000..eaa023fb
--- /dev/null
+++ b/frontend/src/stores/moments.ts
@@ -0,0 +1,56 @@
+import { ref } from "vue";
+import { defineStore } from "pinia";
+import * as api from "@/api/moments";
+import type { MappingChange, MomentsPayload } from "@/api/moments";
+import { useToastStore } from "@/stores/toast";
+import { apiErrorMessage } from "@/api/client";
+
+/**
+ * The moment catalog and this install's mappings (milestone 458 step 6).
+ *
+ * Shared by the rule editor's picker and the Settings section, so the two
+ * cannot offer different moments. The catalog is the product's and changes
+ * only with a release; the mappings and counts change with every write here,
+ * so a write re-reads the whole payload rather than patching it locally.
+ */
+export const useMomentsStore = defineStore("moments", () => {
+  const data = ref<MomentsPayload | null>(null);
+  const loading = ref(false);
+  const failed = ref(false);
+
+  async function fetch(force = false) {
+    if (data.value && !force) return data.value;
+    loading.value = true;
+    try {
+      data.value = await api.getMoments();
+      failed.value = false;
+    } catch {
+      // The picker rides on the rule editor: an unreachable catalog hides
+      // the picker, it does not break the form it sits in.
+      failed.value = true;
+    } finally {
+      loading.value = false;
+    }
+    return data.value;
+  }
+
+  async function change(kind: "map" | "unmap", mapping: MappingChange) {
+    try {
+      if (kind === "map") await api.mapAction(mapping);
+      else await api.unmapAction(mapping);
+    } catch (e) {
+      useToastStore().show(
+        apiErrorMessage(e, kind === "map" ? "Could not add the mapping" : "Could not remove the mapping"),
+        "error",
+      );
+      throw e;
+    }
+    await fetch(true);
+  }
+
+  return {
+    data, loading, failed, fetch,
+    map: (m: MappingChange) => change("map", m),
+    unmap: (m: MappingChange) => change("unmap", m),
+  };
+});
diff --git a/frontend/src/views/SettingsView.vue b/frontend/src/views/SettingsView.vue
index 5250207a..94875ae2 100644
--- a/frontend/src/views/SettingsView.vue
+++ b/frontend/src/views/SettingsView.vue
@@ -8,6 +8,7 @@ import { apiGet, apiPost, apiPut, apiDelete, listGroups, createGroup, deleteGrou
 import type { User } from "@/types/auth";
 import PaginationBar from "@/components/PaginationBar.vue";
 import TagInput from "@/components/TagInput.vue";
+import MomentsSettings from "@/components/MomentsSettings.vue";
 import { fmtDate, fmtLogStamp } from "@/utils/dateFormat";
 import { fetchVersion, type VersionPayload } from "@/api/version";
 
@@ -2222,6 +2223,17 @@ async function deleteUser(userId: number) {
         </div>
       </section>
 
+      <section class="settings-section full-width">
+        <h2>Moments</h2>
+        <p class="section-desc">
+          A rule mounted on a moment arrives whenever that moment happens, whatever the work
+          looks like — which is how a rule about <em>when</em> something is done reaches a session
+          that never mentions it. Mount rules from the rule editor; here is what each moment
+          means, which actions reach it on this install, and what it has delivered.
+        </p>
+        <MomentsSettings />
+      </section>
+
     </div>
 
     <!-- ── Account ── -->
diff --git a/src/scribe/routes/retrieval.py b/src/scribe/routes/retrieval.py
index 88ffe0c7..f21d53c4 100644
--- a/src/scribe/routes/retrieval.py
+++ b/src/scribe/routes/retrieval.py
@@ -13,12 +13,15 @@ So every change to a retrieval dial goes through `set_dial`, from the UI as
 much as from the MCP tool, and the only difference is the `actor` recorded.
 """
 import logging
+from datetime import datetime, timedelta, timezone
 
 from quart import Blueprint, jsonify, request
 
 from scribe.auth import get_current_user_id, login_required
 from scribe.services import moment_actions as moment_actions_svc
 from scribe.services import moments as moments_svc
+from scribe.services import rulebooks as rulebooks_svc
+from scribe.services.retrieval_telemetry import moment_usage
 from scribe.services.retrieval_tuning import set_dial, current_settings, tuning_history
 
 logger = logging.getLogger(__name__)
@@ -115,16 +118,39 @@ async def moments_route():
     actions that reach each one on this install.
 
     The same payload `list_moments` returns, from the same services, so the
-    session and the Settings view cannot name different moments.
+    session and the Settings view cannot name different moments — plus what
+    the view shows beside each one (step 6): `mounted`, how many rules each
+    carries, and `usage`, the deliveries and opens per moment over `days`
+    (the block `retrieval_telemetry` reports as `moment_usage`).
     """
+    uid = get_current_user_id()
+    try:
+        days = max(1, min(int(request.args.get("days", 30)), 365))
+    except ValueError:
+        return jsonify({"error": "days must be a whole number"}), 400
     out = moments_svc.catalog()
-    out.update(await moment_actions_svc.actions_by_moment(get_current_user_id()))
+    out.update(await moment_actions_svc.actions_by_moment(uid))
+    # The catalog is the page; the counts beside it are not worth losing it
+    # over. A failed count is flagged rather than shown as "nothing mounted".
+    try:
+        out["mounted"] = await rulebooks_svc.mount_counts(uid)
+    except Exception:
+        logger.warning("mount counts unreadable", exc_info=True)
+        out["mounted"], out["mounted_failed"] = {}, True
+    out["usage"] = await moment_usage(uid, datetime.now(timezone.utc) - timedelta(days=days))
+    out["usage"]["days"] = days
     return jsonify(out)
 
 
 async def _mapping_change(change):
-    """map/unmap from the browser: the MCP tools' service, recorded as human."""
-    data = await request.get_json()
+    """map/unmap from the browser: the MCP tools' service, recorded as human.
+
+    The mapping comes as a JSON body, or — for DELETE, whose body many
+    clients will not send — as query parameters of the same names.
+    """
+    data = await request.get_json(silent=True)
+    if data is None and request.args:
+        data = request.args.to_dict()
     if not isinstance(data, dict):
         return jsonify({"error": "Expected a JSON object"}), 400
     if not data.get("tool") or not data.get("moment"):
diff --git a/src/scribe/services/retrieval_telemetry.py b/src/scribe/services/retrieval_telemetry.py
index 59eb89f0..1d73ead9 100644
--- a/src/scribe/services/retrieval_telemetry.py
+++ b/src/scribe/services/retrieval_telemetry.py
@@ -22,7 +22,8 @@ from typing import Any
 
 from datetime import datetime, timedelta, timezone
 
-from sqlalchemy import case, func, select
+from sqlalchemy import case, exists, func, select
+from sqlalchemy.orm import aliased
 
 from scribe.models import async_session
 from scribe.models.base import iso
@@ -985,6 +986,94 @@ async def _system_usage(user_id: int | None, since) -> dict:
     return block
 
 
+
+async def moment_usage(user_id: int | None, since) -> dict:
+    """Deliveries and opens per moment (milestone 458 step 6).
+
+    A mounted rule's delivery is a `moment_rule` surfacing whose `detail` is
+    the moment it arrived at — the plugin's catch-all hook, the MCP tools'
+    attached lines and the reply hold all record it so. Per moment:
+
+    - `delivered`: how many times a mounted rule arrived there;
+    - `rules`: how many distinct rules did;
+    - `opened`: how many of those an AGENT then opened (`mcp_*`), at or after
+      their first delivery there in the window;
+    - `last_delivered_at`.
+
+    `opened` is an UPPER BOUND, for by_source's reason: a pull records the
+    door, not the line that prompted it, so a rule delivered at two moments
+    and opened once counts as opened at both. A moment reading near zero is
+    not being flattered by it.
+
+    NO RATIO. A mount is a person's statement that the rule belongs at that
+    moment, not a ranker's guess, so "delivered often, opened rarely" is a
+    question about the rule's wording or the agent, not a bar to tune. The
+    counts sit side by side.
+
+    Its own session and guard (#2663): a failure keeps the shape and adds
+    `moment_usage_failed`, never zeros that read as "nothing happened".
+    """
+    from scribe.services.retrieval_pipeline import MOMENT_RULE_SOURCE
+
+    block: dict = {"by_moment": {}}
+    try:
+        async with async_session() as session:
+            per_rule = (
+                select(
+                    RuleUsageEvent.detail.label("moment"),
+                    RuleUsageEvent.rule_id,
+                    func.count().label("n"),
+                    func.min(RuleUsageEvent.created_at).label("first_at"),
+                    func.max(RuleUsageEvent.created_at).label("last_at"),
+                )
+                .where(
+                    RuleUsageEvent.created_at >= since,
+                    RuleUsageEvent.user_id == user_id,
+                    RuleUsageEvent.event == RULE_SURFACED,
+                    RuleUsageEvent.source == MOMENT_RULE_SOURCE,
+                    RuleUsageEvent.detail.is_not(None),
+                )
+                .group_by(RuleUsageEvent.detail, RuleUsageEvent.rule_id)
+                .subquery()
+            )
+            pull = aliased(RuleUsageEvent)
+            opened = exists().where(
+                pull.rule_id == per_rule.c.rule_id,
+                pull.user_id == user_id,
+                pull.event == RULE_PULLED,
+                # autoescape: `_` is a LIKE wildcard (see the note block).
+                pull.source.startswith("mcp_", autoescape=True),
+                pull.created_at >= per_rule.c.first_at,
+            )
+            rows = (
+                await session.execute(
+                    select(
+                        per_rule.c.moment,
+                        func.sum(per_rule.c.n).label("delivered"),
+                        func.count().label("rules"),
+                        func.count(case((opened, 1))).label("opened"),
+                        func.max(per_rule.c.last_at).label("last_at"),
+                    ).group_by(per_rule.c.moment)
+                )
+            ).all()
+            complete = await _complete_from(session, RuleUsageEvent, user_id)
+    except Exception:
+        logger.warning("moment usage read failed", exc_info=True)
+        block["moment_usage_failed"] = True
+        return block
+
+    block["by_moment"] = {
+        moment: {
+            "delivered": int(delivered or 0),
+            "rules": int(rules or 0),
+            "opened": int(n_opened or 0),
+            "last_delivered_at": iso(last_at),
+        }
+        for moment, delivered, rules, n_opened, last_at in rows
+    }
+    block.update(_coverage(complete.get("*"), since))
+    return block
+
 async def retrieval_summary(
     user_id: int | None, *, days: int = 30, near_miss_samples: int = 0,
 ) -> dict:
@@ -1583,6 +1672,7 @@ async def retrieval_summary(
     rule_usage.update(_coverage((rule_complete or {}).get("*"), since))
     out["rule_usage"] = rule_usage
     out["system_usage"] = await _system_usage(user_id, since)
+    out["moment_usage"] = await moment_usage(user_id, since)
 
     # ── Judged lines (#4772) ─────────────────────────────────────────────
     #
diff --git a/src/scribe/services/rulebooks.py b/src/scribe/services/rulebooks.py
index 8f7d4365..96bfa988 100644
--- a/src/scribe/services/rulebooks.py
+++ b/src/scribe/services/rulebooks.py
@@ -1208,6 +1208,16 @@ async def mounted_moments(user_id: int) -> set[str]:
     tool whose moments carry nothing. A superset is the safe direction — the
     delivery read still scopes by project.
     """
+    return set(await mount_counts(user_id))
+
+
+async def mount_counts(user_id: int) -> dict[str, int]:
+    """How many of this caller's live rules are mounted on each moment.
+
+    The same read as `mounted_moments`, counted — what the Settings view
+    shows beside each moment, so a moment carrying nothing reads as such.
+    Moments with no mount are absent rather than zero.
+    """
     from scribe.models.rulebook import rule_moments as rule_moments_t
     from scribe.services.rule_scope import joined_to_homes, rule_home
 
@@ -1215,13 +1225,14 @@ async def mounted_moments(user_id: int) -> set[str]:
     async with async_session() as session:
         rows = (await session.execute(
             joined_to_homes(
-                select(rule_moments_t.c.moment).distinct()
+                select(rule_moments_t.c.moment, func.count(func.distinct(Rule.id)))
                 .select_from(rule_moments_t)
                 .join(Rule, Rule.id == rule_moments_t.c.rule_id)
             )
             .where(Rule.deleted_at.is_(None), home)
-        )).scalars().all()
-    return set(rows)
+            .group_by(rule_moments_t.c.moment)
+        )).all()
+    return {moment: int(n) for moment, n in rows}
 
 
 async def list_rule_systems(rule_ids: list[int]) -> dict[int, list[dict]]:
diff --git a/tests/test_integration_rule_moments.py b/tests/test_integration_rule_moments.py
index ab99140c..ba3f1347 100644
--- a/tests/test_integration_rule_moments.py
+++ b/tests/test_integration_rule_moments.py
@@ -199,3 +199,64 @@ async def test_the_delivery_lookup_answers_by_home(world):
     # The plugin's "can anything arrive" answer spans every home.
     assert await rulebooks_svc.mounted_moments(uid) >= {"work.finish", "reply.report", "work.deliver"}
     assert not (await rulebooks_svc.mounted_moments(sid)) & {"work.finish", "work.deliver"}
+
+    # Counted the same way for the Settings view: a rule mounted twice counts
+    # once per moment, and another user's mounts are not in the count.
+    counts = await rulebooks_svc.mount_counts(uid)
+    assert counts.get("work.deliver", 0) >= 1 and counts.get("reply.report", 0) >= 1
+    assert set(counts) == await rulebooks_svc.mounted_moments(uid)
+    assert not set(await rulebooks_svc.mount_counts(sid)) & {"work.finish", "work.deliver"}
+
+
+async def test_moment_usage_counts_deliveries_and_the_agent_opens_that_followed(world):
+    """The per-moment readout (step 6), on real SQL: an EXISTS inside a
+    COUNT(CASE …) is a shape no mock can vouch for, and the block's own guard
+    would turn a database refusal into a quiet `moment_usage_failed`."""
+    from datetime import datetime, timedelta, timezone
+
+    from sqlalchemy import delete
+
+    from scribe.models.rule_usage import PULLED, SURFACED, RuleUsageEvent
+    from scribe.services.retrieval_pipeline import MOMENT_RULE_SOURCE
+    from scribe.services.retrieval_telemetry import moment_usage
+
+    uid, sid, rule = world["uid"], world["sid"], world["rule"]
+    other = await rulebooks_svc.create_rule(
+        rule.topic_id, uid, "Close the task with the push",
+        "A task closes in the turn its CI goes green.",
+        when_to_apply="the CI run on a pushed commit has just gone green",
+    )
+    now = datetime.now(timezone.utc)
+
+    def ev(user, rule_id, event, source, ago, detail=None):
+        return RuleUsageEvent(user_id=user, rule_id=rule_id, event=event, source=source,
+                              detail=detail, created_at=now - ago)
+
+    async with async_session() as s:
+        await s.execute(delete(RuleUsageEvent).where(RuleUsageEvent.user_id.in_([uid, sid])))
+        s.add_all([
+            ev(uid, rule.id, SURFACED, MOMENT_RULE_SOURCE, timedelta(hours=3), "work.finish"),
+            ev(uid, rule.id, SURFACED, MOMENT_RULE_SOURCE, timedelta(hours=2), "work.finish"),
+            ev(uid, other.id, SURFACED, MOMENT_RULE_SOURCE, timedelta(hours=1), "work.finish"),
+            ev(uid, rule.id, SURFACED, MOMENT_RULE_SOURCE, timedelta(hours=1), "reply.report"),
+            # An agent opened `rule` after its first work.finish delivery, and
+            # BEFORE its reply.report one — so it counts at the first only.
+            ev(uid, rule.id, PULLED, "mcp_get_rule", timedelta(minutes=150)),
+            # A person opening `other` in the browser is not an agent open.
+            ev(uid, other.id, PULLED, "rest_rule", timedelta(minutes=5)),
+            # A ranked surfacing is not a delivery at a moment.
+            ev(uid, other.id, SURFACED, "pre_tool_rule", timedelta(minutes=5)),
+            # Nor is a delivery older than the window, or someone else's.
+            ev(uid, other.id, SURFACED, MOMENT_RULE_SOURCE, timedelta(days=3), "work.deliver"),
+            ev(sid, rule.id, SURFACED, MOMENT_RULE_SOURCE, timedelta(minutes=5), "work.finish"),
+        ])
+        await s.commit()
+
+    block = await moment_usage(uid, now - timedelta(days=1))
+    assert "moment_usage_failed" not in block
+    assert set(block["by_moment"]) == {"work.finish", "reply.report"}
+    finish = block["by_moment"]["work.finish"]
+    assert (finish["delivered"], finish["rules"], finish["opened"]) == (3, 2, 1)
+    report = block["by_moment"]["reply.report"]
+    assert (report["delivered"], report["rules"], report["opened"]) == (1, 1, 0)
+    assert report["last_delivered_at"]
diff --git a/tests/test_routes_retrieval_tuning.py b/tests/test_routes_retrieval_tuning.py
index 22ab4b14..ecc51db4 100644
--- a/tests/test_routes_retrieval_tuning.py
+++ b/tests/test_routes_retrieval_tuning.py
@@ -133,3 +133,80 @@ async def test_setting_a_dial_to_the_value_it_already_has_records_nothing():
     # And the setting is left alone too: rewriting the same value would bump
     # whatever timestamp the row carries for no reason.
     setter.assert_not_called()
+
+
+# ── the moments view (milestone 458 step 6) ─────────────────────────────
+
+async def _moments_call(handler_name, path, method="GET", **kw):
+    from types import SimpleNamespace
+
+    from quart import Quart, g
+
+    from scribe.routes import retrieval as routes
+
+    app = Quart(__name__)
+    async with app.test_request_context(path, method=method, **kw):
+        g.user = SimpleNamespace(id=7)
+        resp = await getattr(routes, handler_name).__wrapped__()
+        if isinstance(resp, tuple):
+            return await resp[0].get_json(), resp[1]
+        return await resp.get_json(), 200
+
+
+async def test_the_view_gets_the_catalog_with_counts_beside_it():
+    from unittest.mock import AsyncMock, patch
+
+    from scribe.routes import retrieval as routes
+
+    usage = AsyncMock(return_value={"by_moment": {"work.finish": {"delivered": 2}}})
+    with patch.object(routes.moment_actions_svc, "actions_by_moment",
+                      AsyncMock(return_value={"actions": {}, "removed_defaults": []})), \
+         patch.object(routes.rulebooks_svc, "mount_counts", AsyncMock(return_value={"work.finish": 1})), \
+         patch.object(routes, "moment_usage", usage):
+        body, status = await _moments_call("moments_route", "/api/retrieval/moments",
+                                           query_string={"days": "7"})
+    assert status == 200
+    assert body["mounted"] == {"work.finish": 1}
+    assert body["usage"]["days"] == 7
+    assert body["usage"]["by_moment"]["work.finish"]["delivered"] == 2
+    assert {m["name"] for m in body["moments"]} >= {"work.finish", "reply.report"}
+
+
+async def test_a_failed_mount_count_is_flagged_not_shown_as_nothing():
+    from unittest.mock import AsyncMock, patch
+
+    from scribe.routes import retrieval as routes
+
+    with patch.object(routes.moment_actions_svc, "actions_by_moment",
+                      AsyncMock(return_value={"actions": {}, "removed_defaults": []})), \
+         patch.object(routes.rulebooks_svc, "mount_counts", AsyncMock(side_effect=RuntimeError("down"))), \
+         patch.object(routes, "moment_usage", AsyncMock(return_value={"by_moment": {}})):
+        body, status = await _moments_call("moments_route", "/api/retrieval/moments")
+    assert status == 200
+    assert body["mounted"] == {} and body["mounted_failed"] is True
+    assert body["usage"]["days"] == 30
+
+
+async def test_a_mapping_removal_can_come_as_query_parameters():
+    """The browser's DELETE carries no body (api/client.apiDelete), so the
+    mapping it removes arrives in the query string."""
+    from unittest.mock import AsyncMock, patch
+
+    from scribe.routes import retrieval as routes
+
+    unmap = AsyncMock(return_value={"change": "removed this install's mapping"})
+    with patch.object(routes.moment_actions_svc, "unmap_action", unmap):
+        body, status = await _moments_call(
+            "unmap_action_route", "/api/retrieval/moments/mappings", method="DELETE",
+            query_string={"tool": "Bash", "match": "make ship", "moment": "work.deliver"},
+        )
+    assert status == 200
+    assert unmap.await_args.args == (7, "Bash", "make ship", "work.deliver")
+    assert unmap.await_args.kwargs["actor"] == "human"
+
+
+async def test_a_mapping_with_neither_body_nor_parameters_is_refused():
+    body, status = await _moments_call(
+        "unmap_action_route", "/api/retrieval/moments/mappings", method="DELETE",
+    )
+    assert status == 400