diff --git a/web/src/lib/collections/boardColumns.test.ts b/web/src/lib/collections/boardColumns.test.ts
index 99806fedd..139965144 100644
--- a/web/src/lib/collections/boardColumns.test.ts
+++ b/web/src/lib/collections/boardColumns.test.ts
@@ -193,3 +193,14 @@ describe('lanes named after an Object.prototype member (BUG-3208)', () => {
 		});
 	}
 });
+
+describe('a stored value String() cannot convert (BUG-3052)', () => {
+	const HOSTILE = JSON.parse('{"toString":0}');
+	it('laneValue does not throw, and names the value by its JSON', () => {
+		expect(laneValue(HOSTILE)).toBe('{"toString":0}');
+	});
+	it('bucketByColumn keeps the item, in Uncategorized', () => {
+		const result = bucketByColumn([item('h', { status: HOSTILE })], 'status', ['open']);
+		expect(result.get(UNCATEGORIZED)!.map((i) => i.id)).toEqual(['h']);
+	});
+});
diff --git a/web/src/lib/collections/boardColumns.ts b/web/src/lib/collections/boardColumns.ts
index d9dd0dcde..da5adea35 100644
--- a/web/src/lib/collections/boardColumns.ts
+++ b/web/src/lib/collections/boardColumns.ts
@@ -12,6 +12,7 @@
 // lane writes back to the field (clearing it).
 import type { Item } from '$lib/types';
 import { parseFields } from '$lib/types';
+import { safeText } from '$lib/fields/fieldShape';
 
 /** Lane key for items with no (or an unrecognised) group value. */
 export const UNCATEGORIZED = '';
@@ -38,9 +39,11 @@ export const UNCATEGORIZED = '';
  * is what stops the two halves drifting apart again.
  */
 export function laneValue(raw: unknown): string {
-	if (typeof raw === 'string') return raw;
-	if (raw == null) return '';
-	return String(raw);
+	// `safeText`, not `String` (BUG-3052): a stored `{"toString":0}` made
+	// `String(raw)` throw here, and every grouped view reads its lanes through
+	// this function, so one hostile value took the whole list or board down.
+	// Identical to `String` for every value it could already convert.
+	return safeText(raw);
 }
 
 /**
diff --git a/web/src/lib/components/ChildChart.shape.svelte.test.ts b/web/src/lib/components/ChildChart.shape.svelte.test.ts
new file mode 100644
index 000000000..f9e2e8e47
--- /dev/null
+++ b/web/src/lib/components/ChildChart.shape.svelte.test.ts
@@ -0,0 +1,32 @@
+// BUG-3052 unit 1, the `new Date` throw class: the parent's start/end date are
+// stored field values, and `new Date({"toString":0})` throws, which took the
+// whole children section's chart down.
+import { afterEach, describe, expect, it } from 'vitest';
+import { flushSync, mount, unmount } from 'svelte';
+import ChildChart from './ChildChart.svelte';
+
+const kid = (id: string) =>
+	({ id, slug: id, title: id, collection_slug: 'tasks', fields: '{"status":"open"}',
+		created_at: '2026-01-01T00:00:00Z', updated_at: '2026-01-02T00:00:00Z' }) as never;
+
+let instance: ReturnType<typeof mount> | undefined;
+let target: HTMLElement | undefined;
+afterEach(() => {
+	if (instance) unmount(instance);
+	instance = undefined;
+	target?.remove();
+});
+
+describe('ChildChart with a stored date String() cannot convert (BUG-3052)', () => {
+	it('mounts, rather than throwing', () => {
+		const hostile = JSON.parse('{"toString":0}');
+		target = document.body.appendChild(document.createElement('div'));
+		expect(() => {
+			instance = mount(ChildChart, {
+				target: target!,
+				props: { children: [kid('a'), kid('b')], startDate: hostile, endDate: hostile, wsSlug: 'ws' },
+			});
+			flushSync();
+		}).not.toThrow();
+	});
+});
diff --git a/web/src/lib/components/ChildChart.svelte b/web/src/lib/components/ChildChart.svelte
index a1846e9e9..f69ed7f02 100644
--- a/web/src/lib/components/ChildChart.svelte
+++ b/web/src/lib/components/ChildChart.svelte
@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { safeText } from '$lib/fields/fieldShape';
 	import type { Item } from '$lib/types';
 	import { countedChildren, isChildDone } from '$lib/collections/childProgress';
 	import { collectionStore } from '$lib/stores/collections.svelte';
@@ -14,6 +15,15 @@
 	}
 
 	let { children, startDate, endDate, wsSlug }: Props = $props();
+
+	// The parent's `start_date` / `end_date` are stored field values, typed
+	// `string` here but not guaranteed to be one (BUG-3052). `new Date` threw on a
+	// stored `{"toString":0}`. Only an OBJECT (arrays included) is converted, to
+	// its safe text; every primitive — a date string, an epoch number, even a
+	// boolean — reaches `new Date` untouched, exactly as before.
+	function dateInput(v: unknown): unknown {
+		return typeof v === 'object' && v !== null ? safeText(v) : v;
+	}
 	// Each child by its own collection's done field and terminal/abandoned
 	// values. An abandoned child is not part of the work any more and leaves
 	// the burndown entirely (BUG-3195).
@@ -49,7 +59,7 @@
 		// ── Determine start date ──────────────────────────────────────────
 		let start: Date;
 		if (startDate) {
-			start = new Date(startDate);
+			start = new Date(dateInput(startDate) as string);
 		} else {
 			// Infer: earliest created_at among the counted children
 			let earliest = new Date(counted[0].created_at);
@@ -64,7 +74,7 @@
 		// ── Determine end date ────────────────────────────────────────────
 		let end: Date;
 		if (endDate) {
-			end = new Date(endDate);
+			end = new Date(dateInput(endDate) as string);
 		} else if (allDone && completions.length > 0) {
 			// All counted children done → last completion date
 			end = new Date(completions[completions.length - 1].date);
diff --git a/web/src/lib/components/ChildItems.svelte b/web/src/lib/components/ChildItems.svelte
index 922b9b8fb..85c735d0c 100644
--- a/web/src/lib/components/ChildItems.svelte
+++ b/web/src/lib/components/ChildItems.svelte
@@ -14,6 +14,7 @@
 	import { parseFields, parseSchema, formatItemRef } from '$lib/types';
 	import { collectionsNotStaleFor, categoricalValueFor } from '$lib/collections/categoricalFieldValue';
 	import { laneKey } from '$lib/collections/boardColumns';
+	import { safeText } from '$lib/fields/fieldShape';
 	import { dndzone, TRIGGERS, SHADOW_ITEM_MARKER_PROPERTY_NAME } from 'svelte-dnd-action';
 	import type { DndEvent } from 'svelte-dnd-action';
 	import {
@@ -136,7 +137,12 @@
 	let groups = $derived.by(() => {
 		const map = new SvelteMap<string, Item[]>();
 		for (const child of children) {
-			const status = parseFields(child).status ?? 'open';
+			// `safeText`, not the raw value (BUG-3052): the group key feeds a
+			// heading formatter and a `lane:` key template, both of which threw on a
+			// stored `{"toString":0}`, and an array or object keyed a group by
+			// identity, one group per child.
+			const raw = parseFields(child).status;
+			const status = raw == null ? 'open' : safeText(raw);
 			if (!map.has(status)) map.set(status, []);
 			map.get(status)!.push(child);
 		}
diff --git a/web/src/lib/components/ChildItems.svelte.test.ts b/web/src/lib/components/ChildItems.svelte.test.ts
index cb29ce5aa..d72c55d92 100644
--- a/web/src/lib/components/ChildItems.svelte.test.ts
+++ b/web/src/lib/components/ChildItems.svelte.test.ts
@@ -224,3 +224,43 @@ describe('a child status that names an Object.prototype member (BUG-3054)', () =
 		for (const label of labels) expect(label, label).toMatch(/\(1\)$/);
 	});
 });
+
+// BUG-3052 unit 1: a stored status that is not a string. The group heading
+// called `.replace` on it (a number has none) and the lane key template
+// converted it (`{"toString":0}` cannot be converted), so either one threw and
+// the whole children section failed to render.
+describe('a child status that is not a string (BUG-3052)', () => {
+	let target: HTMLElement;
+	let instance: ReturnType<typeof mount> | undefined;
+	const kid = (id: string, fields: string) => ({
+		id, slug: id, title: `Child ${id}`, collection_slug: 'tasks', fields,
+		created_at: '2026-01-01T00:00:00Z', updated_at: '2026-01-01T00:00:00Z',
+	});
+
+	beforeEach(() => {
+		childrenMock.mockClear();
+		childrenMock.mockImplementation(async () => [
+			kid('n', '{"status":5}'),
+			kid('h', '{"status":{"toString":0}}'),
+			kid('o', '{"status":"open"}'),
+		]);
+		target = document.body.appendChild(document.createElement('div'));
+	});
+
+	afterEach(() => {
+		if (instance) unmount(instance);
+		instance = undefined;
+		target.remove();
+		childrenMock.mockImplementation(async () => []);
+	});
+
+	it('renders every child and a heading for each status', async () => {
+		instance = mount(ChildItems, { target, props: { wsSlug: 'ws-1', itemSlug: 'p-1', itemId: 'p-1' } });
+		flushSync();
+		await vi.waitFor(() => expect(target.querySelector('.child-count')).not.toBeNull());
+		flushSync();
+		const text = target.textContent ?? '';
+		for (const id of ['n', 'h', 'o']) expect(text, `child ${id} is rendered`).toContain(`Child ${id}`);
+		expect([...target.querySelectorAll('.group-label')]).toHaveLength(3);
+	});
+});
diff --git a/web/src/lib/components/collections/TableView.listValue.svelte.test.ts b/web/src/lib/components/collections/TableView.listValue.svelte.test.ts
index 8052f067a..3e82e84f3 100644
--- a/web/src/lib/components/collections/TableView.listValue.svelte.test.ts
+++ b/web/src/lib/components/collections/TableView.listValue.svelte.test.ts
@@ -362,3 +362,18 @@ describe('the table chip asks the same permission question as the card (BUG-3068
 		expect(onStatusChange).not.toHaveBeenCalled();
 	});
 });
+
+// BUG-3052 unit 1: a plain text cell whose stored value Svelte's text
+// conversion cannot convert. `{fields[key] ?? ''}` threw and took the table down.
+describe('a text cell holding a value String() cannot convert (BUG-3052)', () => {
+	it('renders the row, with the value visible as its JSON', () => {
+		const coll = collection([{ key: 'note', label: 'Note', type: 'text' }]);
+		const hostile = { id: 'car-h', workspace_id: 'ws1', collection_id: 'c1', slug: 'car-h', title: 'car-h',
+			content: '', fields: '{"note":{"toString":0}}', tags: '[]', status: 'open',
+			created_at: '2026-01-01T00:00:00Z', updated_at: '2026-01-01T00:00:00Z' } as unknown as Item;
+		const screen = render(TableView, { props: { items: [hostile, item('car-2', { note: 'plain' })], collection: coll } as never });
+		expect(screen.container.textContent).toContain('car-h');
+		expect(screen.container.textContent).toContain('{"toString":0}');
+		expect(screen.container.textContent).toContain('plain');
+	});
+});
diff --git a/web/src/lib/components/collections/TableView.svelte b/web/src/lib/components/collections/TableView.svelte
index fe894f2a3..dcedebd98 100644
--- a/web/src/lib/components/collections/TableView.svelte
+++ b/web/src/lib/components/collections/TableView.svelte
@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { safeText } from '$lib/fields/fieldShape';
 	import type { Item, Collection, FieldDef } from '$lib/types';
 	import { isRelationType, relationValuesOf } from '$lib/items/relationFieldTypes';
 	import { narrowRelationRow, relationChipFor, UNRESOLVED_TITLE } from '$lib/collections/relationGroups';
@@ -136,8 +137,10 @@
 				return sortDir === 'asc' ? aVal - bVal : bVal - aVal;
 			}
 
-			const aStr = String(aVal).toLowerCase();
-			const bStr = String(bVal).toLowerCase();
+			// safeText (BUG-3052): String threw on a stored `{"toString":0}`, which
+			// broke the whole sort, and so the table.
+			const aStr = safeText(aVal).toLowerCase();
+			const bStr = safeText(bVal).toLowerCase();
 			const cmp = aStr.localeCompare(bStr);
 			return sortDir === 'asc' ? cmp : -cmp;
 		});
@@ -351,7 +354,9 @@
 								<span class="cell-value">{fields[field.key]}</span>
 							{/if}
 						{:else}
-							<span class="cell-value">{fields[field.key] ?? ''}</span>
+							<!-- safeText (BUG-3052): Svelte's text conversion threw on a
+							     stored `{"toString":0}` and took the table down. -->
+							<span class="cell-value">{safeText(fields[field.key])}</span>
 						{/if}
 					</div>
 				{/each}
diff --git a/web/src/lib/components/common/QuickActionsMenu.svelte b/web/src/lib/components/common/QuickActionsMenu.svelte
index 06c068e1f..b70f8a9a3 100644
--- a/web/src/lib/components/common/QuickActionsMenu.svelte
+++ b/web/src/lib/components/common/QuickActionsMenu.svelte
@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { safeString, safeText } from '$lib/fields/fieldShape';
 	import { localIndex } from '$lib/stores/localIndex.svelte';
 	import { categoricalTemplateValue } from '$lib/utils/quick-action-preview';
 	import { tick, untrack } from 'svelte';
@@ -99,10 +100,10 @@
 			collection: collection.name,
 			content: item?.content ? item.content.slice(0, 200) : '',
 			fields: Object.entries(fields)
-				.map(([k, v]) => `${k}: ${v}`)
+				.map(([k, v]) => `${k}: ${safeString(v)}`)
 				.join(', '),
-			plan: item ? String(fields['plan'] ?? '') : '',
-			phase: item ? String(fields['phase'] ?? fields['plan'] ?? '') : ''
+			plan: item ? safeText(fields['plan']) : '',
+			phase: item ? safeText(fields['phase'] ?? fields['plan']) : ''
 		};
 
 		for (const [key, value] of Object.entries(vars)) {
diff --git a/web/src/lib/components/items/ItemDetail.svelte b/web/src/lib/components/items/ItemDetail.svelte
index 482b26427..f52b773be 100644
--- a/web/src/lib/components/items/ItemDetail.svelte
+++ b/web/src/lib/components/items/ItemDetail.svelte
@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { safeString, safeText } from '$lib/fields/fieldShape';
 	import { page, navigating } from '$app/state';
 	import { tick, onMount, onDestroy, untrack } from 'svelte';
 	import { api, PadApiError, isUpdateConflictError, type ImportURLResponse } from '$lib/api/client';
@@ -4770,7 +4771,8 @@
 		// first report of a load is ChildItems' initial fetch, which the load's
 		// own GET /progress already answers, so a load issues no extra request.
 		const sig = items
-			.map((i) => `${i.id}:${parseFields(i).status ?? ''}`)
+			// safeText (BUG-3052): `${}` threw on a stored `{"toString":0}`.
+			.map((i) => `${i.id}:${safeText(parseFields(i).status)}`)
 			.sort()
 			.join('|');
 		const sameLoad = childrenSigGen === loadGeneration;
@@ -4804,7 +4806,8 @@
 
 	function formatFieldDisplay(value: any): string {
 		if (value === null || value === undefined || value === '') return '—';
-		return String(value).replace(/_/g, ' ').replace(/\b\w/g, c => c.toUpperCase());
+		// safeText (BUG-3052): String threw on a stored `{"toString":0}`.
+		return safeText(value).replace(/_/g, ' ').replace(/\b\w/g, c => c.toUpperCase());
 	}
 
 	function relationLabel(ref?: string, title?: string, fallback?: string): string {
@@ -5899,7 +5902,7 @@
 					<button
 						type="button"
 						class="source-chip"
-						title={`Source: ${fields.pad_source_url}${fields.pad_imported_at ? `\nImported: ${fields.pad_imported_at}` : ''}`}
+						title={`Source: ${safeString(fields.pad_source_url)}${fields.pad_imported_at ? `\nImported: ${safeString(fields.pad_imported_at)}` : ''}`}
 						disabled={refreshing}
 						onclick={refreshFromSource}
 					>
diff --git a/web/src/lib/components/share/shareView.test.ts b/web/src/lib/components/share/shareView.test.ts
index ca74d16c5..ec6df9551 100644
--- a/web/src/lib/components/share/shareView.test.ts
+++ b/web/src/lib/components/share/shareView.test.ts
@@ -198,3 +198,12 @@ describe('groupItems with falsy-but-present values', () => {
 		expect(total).toBe(items.length);
 	});
 });
+
+describe('matchesFilter on a stored value String() cannot convert (BUG-3052)', () => {
+	it('does not throw, and matches nothing it should not', async () => {
+		const { matchesFilter } = await import('./shareView');
+		const item = { fields: JSON.parse('{"status":{"toString":0}}') } as never;
+		expect(matchesFilter(item, { field: 'status', op: 'eq', value: 'open' })).toBe(false);
+		expect(matchesFilter(item, { field: 'status', op: 'in', value: ['open'] })).toBe(false);
+	});
+});
diff --git a/web/src/lib/components/share/shareView.ts b/web/src/lib/components/share/shareView.ts
index 3f8d19383..8f9b2520d 100644
--- a/web/src/lib/components/share/shareView.ts
+++ b/web/src/lib/components/share/shareView.ts
@@ -17,6 +17,7 @@
 import type { FieldDef } from '$lib/types';
 import { isRelationType, relationValuesOf } from '$lib/items/relationFieldTypes';
 import { UNPARENTED_FILTER_FIELD } from '$lib/collections/unparentedFilter';
+import { safeString, safeText } from '$lib/fields/fieldShape';
 
 // Re-exported so existing/future imports of `UNPARENTED_FILTER_FIELD` from
 // this module keep working — the canonical definition lives in
@@ -244,16 +245,19 @@ export function matchesFilter(item: PublicItem, filter: unknown): boolean {
 	if (typeof f.field !== 'string') return true;
 	if (f.field === UNPARENTED_FILTER_FIELD) return true;
 	const fieldVal = item.fields[f.field];
+	// `safeText` / `safeString`, not `String` (BUG-3052): a stored
+	// `{"toString":0}` made `String` throw, which took the whole shared view
+	// down. Same comparisons, same answers, for every value `String` handled.
 	if (f.op === 'eq') {
-		return String(fieldVal ?? '') === String(f.value ?? '');
+		return safeText(fieldVal) === safeText(f.value);
 	}
 	if (f.op === 'in') {
-		const wanted = Array.isArray(f.value) ? f.value.map((v) => String(v)) : [String(f.value)];
+		const wanted = Array.isArray(f.value) ? f.value.map((v) => safeString(v)) : [safeString(f.value)];
 		// Tags-style array fields: match if any item value is wanted.
 		if (Array.isArray(fieldVal)) {
-			return fieldVal.some((v) => wanted.includes(String(v)));
+			return fieldVal.some((v) => wanted.includes(safeString(v)));
 		}
-		return wanted.includes(String(fieldVal ?? ''));
+		return wanted.includes(safeText(fieldVal));
 	}
 	return true;
 }
diff --git a/web/src/lib/fields/fieldShape.test.ts b/web/src/lib/fields/fieldShape.test.ts
new file mode 100644
index 000000000..a66be8083
--- /dev/null
+++ b/web/src/lib/fields/fieldShape.test.ts
@@ -0,0 +1,41 @@
+// BUG-3052 unit 1: the read-side text conversion never throws.
+import { describe, expect, it } from 'vitest';
+import { safeString, safeText } from './fieldShape';
+
+// A value JSON.parse happily produces, on which String() / `${}` / new Date() throw.
+const HOSTILE = JSON.parse('{"toString":0}');
+
+describe('safeText', () => {
+	it('control: String() really does throw on the hostile value', () => {
+		// Without this, every leg below could pass on a runtime where the value is
+		// harmless, and measure nothing.
+		expect(() => String(HOSTILE)).toThrow();
+	});
+
+	it('does not throw on the hostile value, and keeps it visible as its JSON', () => {
+		expect(safeText(HOSTILE)).toBe('{"toString":0}');
+		expect(safeText([HOSTILE, 'a'])).toBe('[{"toString":0},"a"]');
+	});
+
+	it('matches String() exactly for every value String() can convert', () => {
+		for (const v of ['open', '', 0, 5, false, true, ['a', 'b'], [], { a: 1 }, [1, [2, 3]]]) {
+			expect(safeText(v), JSON.stringify(v)).toBe(String(v));
+		}
+	});
+
+	it('reads null and undefined as no text', () => {
+		expect(safeText(null)).toBe('');
+		expect(safeText(undefined)).toBe('');
+	});
+});
+
+describe('safeString', () => {
+	it('is String() for every value String() converts, null and undefined included', () => {
+		for (const v of [null, undefined, 'x', 0, true, ['a', 'b'], { a: 1 }]) {
+			expect(safeString(v)).toBe(String(v));
+		}
+	});
+	it('does not throw on the hostile value', () => {
+		expect(safeString(HOSTILE)).toBe('{"toString":0}');
+	});
+});
diff --git a/web/src/lib/fields/fieldShape.ts b/web/src/lib/fields/fieldShape.ts
new file mode 100644
index 000000000..1196ab64b
--- /dev/null
+++ b/web/src/lib/fields/fieldShape.ts
@@ -0,0 +1,66 @@
+// The read-side shape layer for item field values (BUG-3052).
+//
+// An item's `fields` is a JSON blob, and a field's DECLARED type is not a
+// promise about what is STORED: the schema editor sets any type on any key and
+// nothing rewrites existing values when a type changes. So a reader of
+// `fields[key]` can be handed a string, number, boolean, null, array or object,
+// and a JSON object can even carry a non-callable `toString`
+// (`{"toString":0}`), on which `String(v)`, `${v}` and `new Date(v)` THROW
+// ("Cannot convert object to primitive value") and take the whole view down.
+//
+// This module is where a raw field value is turned into something a surface
+// can use. It is the checklist as well as the code: the population below is
+// what the lead ruled should route through here (one layer, not per-surface
+// guards; no source scanner — the table IS the enforcement).
+//
+// ## Population (BUG-3052 census on main 4d4ab1d6; full table on the trail)
+//
+// Unit 1 — THROWS (routed through `safeText` in this change):
+//   - laneValue (boardColumns.ts) → list grouping, board buckets + drops,
+//     relation lanes, shareView groupItems
+//   - TableView column sort
+//   - ChildItems group heading + its lane key
+//   - shareView matchesFilter; the /s/[token] field formatter
+//   - QuickActionsMenu + quick-action-preview prompt variables
+//   - playbooks page trigger sort
+//   - ItemDetail: children signature, computed-field text, imported-at title
+//   - ChildChart start/end dates
+// Unit 2 — renders garbage / writes back a changed type (FieldEditor,
+//   TableView cells): `readAs` + a mismatch marker; waits on a UX ruling.
+// Unit 3 — web misfilters (strict `===` / `includes` on raw values).
+// Unit 4 — server SQL, split out as BUG-3221.
+
+/**
+ * Exactly `String(raw)`, except it never throws. For a call site that used a
+ * bare `String(v)` and whose output for `null` / `undefined` (`'null'`,
+ * `'undefined'`) is part of what it compares — so swapping in `safeText` would
+ * change an answer rather than only remove a crash.
+ *
+ * Identical to `String` whenever `String` would not throw: `'a,b'` for
+ * `['a','b']`, `'[object Object]'` for a plain object, `'0'`, `'false'`. Only the
+ * values `String` cannot convert fall back to their JSON text, so they stay
+ * visible and distinguishable instead of taking the surface down.
+ */
+export function safeString(raw: unknown): string {
+	try {
+		return String(raw);
+	} catch {
+		try {
+			return JSON.stringify(raw) ?? '';
+		} catch {
+			return '[unreadable value]';
+		}
+	}
+}
+
+/**
+ * A field value as display/compare TEXT, for any value JSON can hold. TOTAL:
+ * it never throws. `null` / `undefined` read as `''` (no text) — what every
+ * caller that wrote `String(v ?? '')` or its own null guard wanted — and every
+ * other value reads exactly as `safeString` does.
+ */
+export function safeText(raw: unknown): string {
+	if (typeof raw === 'string') return raw;
+	if (raw == null) return '';
+	return safeString(raw);
+}
diff --git a/web/src/lib/utils/quick-action-preview.shape.test.ts b/web/src/lib/utils/quick-action-preview.shape.test.ts
new file mode 100644
index 000000000..84f70d174
--- /dev/null
+++ b/web/src/lib/utils/quick-action-preview.shape.test.ts
@@ -0,0 +1,20 @@
+// BUG-3052 unit 1: the prompt-variable context tolerates stored values String()
+// cannot convert. `categoricalTemplateValue`, the `fields` line and plan/phase
+// all converted raw values and threw on `{"toString":0}`.
+import { describe, expect, it } from 'vitest';
+import { contextFromItem } from './quick-action-preview';
+
+describe('contextFromItem with a hostile stored value (BUG-3052)', () => {
+	it('does not throw, and keeps the value visible as its JSON', () => {
+		const item = {
+			id: 'i1', title: 'T', content: '', item_number: 1,
+			fields: '{"status":{"toString":0},"plan":{"toString":0},"note":"x"}',
+		} as never;
+		const collection = { slug: 'tasks', name: 'Tasks', prefix: 'TASK', schema: '{"fields":[]}' } as never;
+		const ctx = contextFromItem(item, collection);
+		expect(ctx.status).toBe('{"toString":0}');
+		expect(ctx.plan).toBe('{"toString":0}');
+		expect(ctx.fields).toContain('status: {"toString":0}');
+		expect(ctx.fields).toContain('note: x');
+	});
+});
diff --git a/web/src/lib/utils/quick-action-preview.ts b/web/src/lib/utils/quick-action-preview.ts
index 105db20a2..b40d902b1 100644
--- a/web/src/lib/utils/quick-action-preview.ts
+++ b/web/src/lib/utils/quick-action-preview.ts
@@ -1,4 +1,5 @@
 import type { Collection, Item, ItemIndexRow } from '$lib/types';
+import { safeString, safeText } from '$lib/fields/fieldShape';
 import { formatItemRef, parseFields } from '$lib/types';
 import { fieldDefFor } from '$lib/collections/categoricalFieldValue';
 import { isRelationType, relationValuesOf } from '$lib/items/relationFieldTypes';
@@ -60,7 +61,7 @@ export function categoricalTemplateValue(
 ): string {
 	const field = collection ? fieldDefFor([collection], collection.slug, key) : undefined;
 	if (!field || !isRelationType(field.type)) {
-		return raw === null || raw === undefined ? '' : String(raw);
+		return safeText(raw);
 	}
 	const ids = relationValuesOf(field.type, raw);
 	const labels: string[] = [];
@@ -135,11 +136,13 @@ export function contextFromItem(
 		priority: categoricalTemplateValue(collection, 'priority', fields['priority'], resolve),
 		collection: collection.name,
 		content: item.content ? item.content.slice(0, 200) : '',
+		// safeString / safeText, not `${v}` / String (BUG-3052): a stored
+		// `{"toString":0}` threw here. Same text for every value String handled.
 		fields: Object.entries(fields)
-			.map(([k, v]) => `${k}: ${v}`)
+			.map(([k, v]) => `${k}: ${safeString(v)}`)
 			.join(', '),
-		plan: String(fields['plan'] ?? ''),
-		phase: String(fields['phase'] ?? fields['plan'] ?? '')
+		plan: safeText(fields['plan']),
+		phase: safeText(fields['phase'] ?? fields['plan'])
 	};
 }
 
diff --git a/web/src/routes/[username]/[workspace]/playbooks/+page.svelte b/web/src/routes/[username]/[workspace]/playbooks/+page.svelte
index a9a6fcaf4..4f3e62628 100644
--- a/web/src/routes/[username]/[workspace]/playbooks/+page.svelte
+++ b/web/src/routes/[username]/[workspace]/playbooks/+page.svelte
@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { safeText } from '$lib/fields/fieldShape';
 	import { page } from '$app/state';
 	import { ownValue } from '$lib/utils/ownValue';
 	import { goto } from '$app/navigation';
@@ -220,7 +221,9 @@
 			// what it was sorted BY, which is the same value wearing a different hat.
 			const sa = ownValue(STATUS_ORDER, declaredStatusOf(fa)) ?? 1, sb = ownValue(STATUS_ORDER, declaredStatusOf(fb)) ?? 1;
 			if (sa !== sb) return sa - sb;
-			const ta = fa.trigger ?? '', tb = fb.trigger ?? '';
+			// safeText (BUG-3052): a non-string trigger has no localeCompare, and a
+			// `{"toString":0}` one threw inside the sort.
+			const ta = safeText(fa.trigger), tb = safeText(fb.trigger);
 			if (ta !== tb) return ta.localeCompare(tb);
 			return a.title.localeCompare(b.title);
 		});
@@ -584,8 +587,8 @@
 					     schema lands. The card still renders, with its title, trigger
 					     and steps — the affordance is withheld, not the row. -->
 					{@const status = playbooksCollection ? declaredStatus : ''}
-					{@const trigger = fields.trigger ?? 'manual'}
-					{@const scope = fields.scope ?? 'all'}
+					{@const trigger = fields.trigger == null ? 'manual' : safeText(fields.trigger)}
+					{@const scope = fields.scope == null ? 'all' : safeText(fields.scope)}
 					{@const steps = countSteps(item.content)}
 					{@const isExpanded = expandedId === item.id}
 					<div class="card" class:card-draft={status === 'draft'} class:card-deprecated={status === 'deprecated'}>
diff --git a/web/src/routes/s/[token]/+page.svelte b/web/src/routes/s/[token]/+page.svelte
index 251c3f217..efe6bb302 100644
--- a/web/src/routes/s/[token]/+page.svelte
+++ b/web/src/routes/s/[token]/+page.svelte
@@ -1,4 +1,5 @@
 <script lang="ts">
+	import { safeText } from '$lib/fields/fieldShape';
 	import { page } from '$app/state';
 	import { onMount } from 'svelte';
 	import { api, withRequestDeadline } from '$lib/api/client';
@@ -444,9 +445,10 @@
 	});
 
 	function formatFieldValue(value: unknown): string {
-		if (value === null || value === undefined) return '';
-		if (Array.isArray(value)) return value.join(', ');
-		return String(value);
+		// `safeText` (BUG-3052): `join` and `String` threw on a stored
+		// `{"toString":0}`, element or whole, and took the shared page down.
+		if (Array.isArray(value)) return value.map((v) => safeText(v)).join(', ');
+		return safeText(value);
 	}
 
 	function formatFieldLabel(key: string): string {