diff --git a/frontend/src/lib/generated/api.ts b/frontend/src/lib/generated/api.ts
index 5c3f05a3..44151d3d 100644
--- a/frontend/src/lib/generated/api.ts
+++ b/frontend/src/lib/generated/api.ts
@@ -2381,6 +2381,14 @@ export interface components {
             documentCount?: number;
             alias?: string;
             notes?: string;
+            /** Format: date */
+            birthDate?: string;
+            /** @enum {string} */
+            birthDatePrecision?: "DAY" | "MONTH" | "SEASON" | "YEAR" | "RANGE" | "APPROX" | "UNKNOWN";
+            /** Format: date */
+            deathDate?: string;
+            /** @enum {string} */
+            deathDatePrecision?: "DAY" | "MONTH" | "SEASON" | "YEAR" | "RANGE" | "APPROX" | "UNKNOWN";
             personType?: string;
             familyMember?: boolean;
             provisional?: boolean;
@@ -2490,10 +2498,10 @@ export interface components {
             /** Format: int32 */
             number?: number;
             sort?: components["schemas"]["SortObject"];
-            first?: boolean;
-            last?: boolean;
             /** Format: int32 */
             numberOfElements?: number;
+            first?: boolean;
+            last?: boolean;
             empty?: boolean;
         };
         PageableObject: {
diff --git a/frontend/src/lib/shared/discussion/MentionDropdown.svelte b/frontend/src/lib/shared/discussion/MentionDropdown.svelte
index 0dd6a0b7..2185ad12 100644
--- a/frontend/src/lib/shared/discussion/MentionDropdown.svelte
+++ b/frontend/src/lib/shared/discussion/MentionDropdown.svelte
@@ -15,7 +15,9 @@ import { m } from '$lib/paraglide/messages.js';
 // — see Felix #3 on PR #629.
 import { MAX_QUERY_LENGTH } from './mentionConstants';
 
-type Person = components['schemas']['Person'];
+// PersonSummaryDTO, not Person: /api/persons list items are the summary projection.
+// Typing them as the full entity hid a runtime bug (missing date fields, #812).
+type Person = components['schemas']['PersonSummaryDTO'];
 
 // The dropdown receives a single reactive state object. PersonMentionEditor
 // mutates fields on this object (model.items = ..., etc.) and Svelte's $state
diff --git a/frontend/src/lib/shared/discussion/MentionDropdown.svelte.test.ts b/frontend/src/lib/shared/discussion/MentionDropdown.svelte.test.ts
index a73dcf93..74976e6b 100644
--- a/frontend/src/lib/shared/discussion/MentionDropdown.svelte.test.ts
+++ b/frontend/src/lib/shared/discussion/MentionDropdown.svelte.test.ts
@@ -7,7 +7,9 @@ import MentionDropdownFixture from './MentionDropdown.test-fixture.svelte';
 import { m } from '$lib/paraglide/messages.js';
 import type { components } from '$lib/generated/api';
 
-type Person = components['schemas']['Person'];
+// PersonSummaryDTO mirrors the real runtime shape: /api/persons list items are
+// the summary projection, not the full entity (#812).
+type Person = components['schemas']['PersonSummaryDTO'];
 
 afterEach(cleanup);
 
diff --git a/frontend/src/lib/shared/discussion/MentionDropdown.test-fixture.svelte b/frontend/src/lib/shared/discussion/MentionDropdown.test-fixture.svelte
index 4a69d9e5..e0705f0b 100644
--- a/frontend/src/lib/shared/discussion/MentionDropdown.test-fixture.svelte
+++ b/frontend/src/lib/shared/discussion/MentionDropdown.test-fixture.svelte
@@ -3,7 +3,7 @@ import { untrack } from 'svelte';
 import MentionDropdown from './MentionDropdown.svelte';
 import type { components } from '$lib/generated/api';
 
-type Person = components['schemas']['Person'];
+type Person = components['schemas']['PersonSummaryDTO'];
 type DropdownState = {
 	items: Person[];
 	command: (item: Person) => void;
diff --git a/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte b/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte
index 274f97ce..d9059c62 100644
--- a/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte
+++ b/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte
@@ -12,7 +12,9 @@ import MentionDropdown from './MentionDropdown.svelte';
 import { createMentionNodeView } from './mentionNodeView';
 import { MAX_QUERY_LENGTH, SEARCH_DEBOUNCE_MS, SEARCH_RESULT_LIMIT } from './mentionConstants';
 
-type Person = components['schemas']['Person'];
+// PersonSummaryDTO, not Person: /api/persons list items are the summary projection.
+// Typing them as the full entity hid a runtime bug (missing date fields, #812).
+type Person = components['schemas']['PersonSummaryDTO'];
 
 type Props = {
 	value: string;
@@ -216,14 +218,15 @@ const controller = createMentionController();
 // reflected data-person-id or the search input).
 function commitRelink(pos: number): CommitFn {
 	return (item: Person) => {
-		if (!editor) return;
+		if (!editor || !item.id) return;
+		const personId = item.id;
 		editor
 			.chain()
 			.focus()
 			.command(({ tr, state }) => {
 				const node = state.doc.nodeAt(pos);
 				if (!node || node.type.name !== 'mention') return false;
-				tr.setNodeMarkup(pos, undefined, { ...node.attrs, personId: item.id });
+				tr.setNodeMarkup(pos, undefined, { ...node.attrs, personId });
 				return true;
 			})
 			.run();
@@ -364,8 +367,10 @@ onMount(() => {
 					render() {
 						const buildFreshCommit = (loose: LooseRenderProps): CommitFn => {
 							const clippedQuery = loose.query.slice(0, MAX_QUERY_LENGTH);
-							return (item: Person) =>
+							return (item: Person) => {
+								if (!item.id) return;
 								loose.command({ personId: item.id, displayName: clippedQuery });
+							};
 						};
 						return {
 							onStart(renderProps) {
diff --git a/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts b/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts
index cbc06aa7..d0f3912a 100644
--- a/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts
+++ b/frontend/src/lib/shared/discussion/PersonMentionEditor.svelte.spec.ts
@@ -16,7 +16,7 @@ import { m } from '$lib/paraglide/messages.js';
 // module so the test cannot drift from production. Sara on PR #629 round 3.
 import { SEARCH_DEBOUNCE_MS } from './mentionConstants';
 
-type Person = components['schemas']['Person'];
+type Person = components['schemas']['PersonSummaryDTO'];
 type PersonMention = components['schemas']['PersonMention'];
 
 /**