diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5890e280..ccd67df8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -71,6 +71,10 @@ Format follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Under the hood
 
+- **The system list says more about each system.** Each one now comes with its description, its
+  author and how many players' characters are played in it (NPCs aren't counted), for the
+  builder's MY SYSTEMS page to show under each name.
+
 - **The system builder opens.** OPEN IN BUILDER in SYSTEMS.EXE, or CREATE for a new system, opens
   the builder over the whole window. Its sidebar is an icon rail like the map's, which widens to
   show the names when you point at it: EXIT TO MAP where the power button sits, MY SYSTEMS, the
diff --git a/backend/__tests__/system_builder_store.test.js b/backend/__tests__/system_builder_store.test.js
index 27d9d937..94158ead 100644
--- a/backend/__tests__/system_builder_store.test.js
+++ b/backend/__tests__/system_builder_store.test.js
@@ -139,6 +139,26 @@ describe('the systems routes', () => {
     expect(res.body.problems).toEqual([]);
     const [only] = await list();
     expect(only).toMatchObject({ id: res.body.id, name: 'Vault Knights', version: 0, published: false, unpublishedChanges: true, installed: false, problemCount: 0 });
+    // Nothing yet to describe it, credit or play in it.
+    expect(only).toMatchObject({ description: '', author: '', characterCount: 0 });
+  });
+
+  it('says what each system\'s line shows: its draft\'s description and author, and its players\' characters', async () => {
+    const { id } = (await create({ definition: { format: 1, name: 'Hearth', description: '  Low fantasy by one fire. ', author: 'Cody' } })).body;
+    const other = (await create({ name: 'Ember' })).body.id;
+    const sheet = (username, system, isNpc) => run(db, 'INSERT INTO character_sheets (username, system, data, is_npc) VALUES (?, ?, ?, ?)', [username, system, '{}', isNpc]);
+    await sheet('vex', id, 0);
+    await sheet('rook', id, 0);
+    await sheet('gm', id, 1);
+    await sheet('vex', other, 0);
+    await sheet('vex', 'cities_without_number', 0);
+    await run(db, 'INSERT INTO character_sheets (username, system, data, is_npc) VALUES (?, ?, ?, NULL)', ['ghost', id, '{}']);
+    const byId = Object.fromEntries((await list()).map((s) => [s.id, s]));
+    expect(byId[id]).toMatchObject({ description: 'Low fantasy by one fire.', author: 'Cody', characterCount: 3 });
+    expect(byId[other]).toMatchObject({ description: '', author: '', characterCount: 1 });
+    // The draft's, not the published copy's: what the GM is working on.
+    await request(app).put(`/api/systems/${id}/draft`).set(bearer(GM)).send({ definition: { format: 1, name: 'Hearth', description: 'Rewritten.', author: 42 } });
+    expect((await list()).find((s) => s.id === id)).toMatchObject({ description: 'Rewritten.', author: '' });
   });
 
   it('refuses a name another system has, whatever its capitals, so the GM can pick another', async () => {
diff --git a/backend/systemBuilder/store.js b/backend/systemBuilder/store.js
index 366ea20b..057dfbe1 100644
--- a/backend/systemBuilder/store.js
+++ b/backend/systemBuilder/store.js
@@ -39,30 +39,42 @@ const problemsOf = (draft) => {
   return checked.fatal ? [{ where: 'definition', message: checked.fatal }] : checked.problems;
 };
 
+/** A definition's text field, or '' when it has none. */
+const textOf = (definition, key) => (definition && typeof definition[key] === 'string' ? definition[key].trim() : '');
+
 /**
  * Every system, newest change first, without their definitions. Each says how many problems its
- * draft has, so SYSTEMS.EXE can badge them without fetching every system.
+ * draft has, so the builder's MY SYSTEMS can badge them without fetching every system, and what
+ * its line shows (approved mockup builder-my-systems, 2026-10-06): the draft's description and
+ * author, and how many players' characters are played in it (NPC sheets are not counted).
  */
 const listSystems = (db, cb) => {
   db.all(
-    `SELECT id, name, version, draft, published, source_hash, updated_at, published_at
-     FROM custom_systems WHERE deleted_at IS NULL ORDER BY updated_at DESC, name`,
+    `SELECT s.id, s.name, s.version, s.draft, s.published, s.source_hash, s.updated_at, s.published_at,
+       (SELECT COUNT(*) FROM character_sheets c WHERE c.system = s.id AND COALESCE(c.is_npc, 0) = 0) AS character_count
+     FROM custom_systems s WHERE s.deleted_at IS NULL ORDER BY s.updated_at DESC, s.name`,
     [],
     (err, rows) => {
       if (err) return cb(err);
-      cb(null, rows.map((r) => ({
-        id: r.id,
-        name: r.name,
-        version: r.version,
-        updatedAt: r.updated_at,
-        publishedAt: r.published_at,
-        published: r.published != null,
-        // Compared as stored text: the draft is written exactly as publishing copies it.
-        unpublishedChanges: r.published == null || r.draft !== r.published,
-        // Installed from a file, rather than made here: only an install records the file's hash.
-        installed: r.source_hash != null,
-        problemCount: problemsOf(parse(r.draft)).length,
-      })));
+      cb(null, rows.map((r) => {
+        const draft = parse(r.draft);
+        return {
+          id: r.id,
+          name: r.name,
+          version: r.version,
+          updatedAt: r.updated_at,
+          publishedAt: r.published_at,
+          published: r.published != null,
+          // Compared as stored text: the draft is written exactly as publishing copies it.
+          unpublishedChanges: r.published == null || r.draft !== r.published,
+          // Installed from a file, rather than made here: only an install records the file's hash.
+          installed: r.source_hash != null,
+          problemCount: problemsOf(draft).length,
+          description: textOf(draft, 'description'),
+          author: textOf(draft, 'author'),
+          characterCount: r.character_count,
+        };
+      }));
     },
   );
 };