⚙️ Engine: Optimize conversational history pruning & authenticated release fetching

src/__tests__/releases-api.test.ts

@@ -0,0 +1,59 @@
+import { describe, expect, it, vi, beforeEach } from 'vitest';
+import { GET } from '../pages/api/releases';
+import * as githubReleases from '../utils/github-releases';
+import { LATEST_RELEASE_SNAPSHOT } from '../data/latest-release';
+import { toVisitorRelease } from '../utils/visitor-changelog';
+
+type GetContext = Parameters<typeof GET>[0];
+
+function createContext(request = new Request('https://example.com/api/releases')) {
+  return {
+    request,
+    locals: {},
+  } as unknown as GetContext;
+}
+
+const mockRelease: githubReleases.SiteRelease = {
+  body: '- 41fe7ae feat: rewrite /experimental/now/ for visitors (#523)',
+  publishedAt: '2026-08-16T21:12:02Z',
+  title: '2026.08.16.2111',
+  url: 'https://github.com/alehar9320/astro-cloudflare-personal-website/releases/tag/2026.08.16.2111',
+  version: '2026.08.16.2111',
+};
+
+describe('releases API route', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('returns formatted visitor releases from GitHub', async () => {
+    vi.spyOn(githubReleases, 'fetchGitHubReleases').mockResolvedValue([mockRelease]);
+
+    const response = await GET(createContext());
+    expect(response.status).toBe(200);
+    expect(response.headers.get('content-type')).toBe('application/json');
+
+    const json = await response.json();
+    expect(json).toEqual([toVisitorRelease(mockRelease)]);
+  });
+
+  it('falls back to LATEST_RELEASE_SNAPSHOT if GitHub releases are empty', async () => {
+    vi.spyOn(githubReleases, 'fetchGitHubReleases').mockResolvedValue([]);
+
+    const response = await GET(createContext());
+    expect(response.status).toBe(200);
+
+    const json = await response.json();
+    expect(json).toEqual([toVisitorRelease(LATEST_RELEASE_SNAPSHOT)]);
+  });
+
+  it('handles errors gracefully by falling back to LATEST_RELEASE_SNAPSHOT', async () => {
+    vi.spyOn(githubReleases, 'fetchGitHubReleases').mockRejectedValue(new Error('GitHub error'));
+
+    const response = await GET(createContext());
+    expect(response.status).toBe(200);
+
+    const json = await response.json();
+    expect(json).toEqual([toVisitorRelease(LATEST_RELEASE_SNAPSHOT)]);
+  });
+});

src/pages/api/release-summary.ts

@@ -100,7 +100,8 @@ async function summarize(request: Request) {
     }
 
     if (!latest) {
-      const releases = await fetchGitHubReleases();
+      const token = bindings.GITHUB_TOKEN?.trim();
+      const releases = await fetchGitHubReleases(fetch, undefined, token ? { token } : undefined);
       latest = releases[0] ?? null;
       if (latest) source = 'github';
     }

src/pages/api/releases.ts

@@ -2,7 +2,9 @@ import type { APIRoute } from 'astro';
 import { env } from 'cloudflare:workers';
 import { LATEST_RELEASE_SNAPSHOT } from '../../data/latest-release';
 import { fetchGitHubReleases, type SiteRelease } from '../../utils/github-releases';
-import { toVisitorChangelogTitle, toVisitorRelease } from '../../utils/visitor-changelog';
+import { toVisitorRelease } from '../../utils/visitor-changelog';
+
+// toVisitorRelease formats each release using toVisitorChangelogTitle
 
 const jsonHeaders = {
   'content-type': 'application/json',
@@ -29,20 +31,7 @@ function readEnv(): ReleasesEnv {
 }
 
 function visitorReleases(releases: SiteRelease[]) {
-  return releases.map((release) => {
-    const visitor = toVisitorRelease(release);
-    return {
-      ...visitor,
-      body: visitor.body
-        .split('\n')
-        .map((line) => {
-          const bullet = line.match(/^([-*+]\s+)(.*)$/);
-          if (!bullet) return toVisitorChangelogTitle(line);
-          return `${bullet[1]}${toVisitorChangelogTitle(bullet[2])}`;
-        })
-        .join('\n'),
-    };
-  });
+  return releases.map(toVisitorRelease);
 }
 
 export const GET: APIRoute = async () => {

src/utils/chat-logic.test.ts

@@ -101,5 +101,17 @@ describe('chat logic utilities', () => {
       expect(pruned).toHaveLength(1);
       expect(pruned[0].content).toBe('short');
     });
+
+    it('drops leading assistant messages so pruned history begins with a user turn', () => {
+      const longContent = 'x'.repeat(MAX_TOTAL_CONTENT_LENGTH - 20);
+      const messages: ChatMessage[] = [
+        { role: 'user', content: longContent },
+        { role: 'assistant', content: 'Middle assistant reply' },
+        { role: 'user', content: 'Final user question' },
+      ];
+      const pruned = pruneMessages(messages);
+      expect(pruned[0].role).toBe('user');
+      expect(pruned[0].content).toBe('Final user question');
+    });
   });
 });

src/utils/chat-logic.ts

@@ -41,6 +41,11 @@ export function pruneMessages(messages: ChatMessage[]): ChatMessage[] {
     totalLength -= pruned.shift()!.content.length;
   }
 
+  while (pruned.length > 1 && pruned[0].role === 'assistant') {
+    // biome-ignore lint/style/noNonNullAssertion: loop guard ensures shift() returns an element
+    totalLength -= pruned.shift()!.content.length;
+  }
+
   return pruned;
 }