W7 T8: bun run audit:manifest and the prompt-audit procedure

scripts/prompt-audit-manifest.ts prints the slices a contributor feeds to
/claude-api prompt-audit: shared instructions (CLAUDE.md, overlays, preamble
resolvers), resolvers, skill templates (a skill stays in one slice),
model-request code and tests that pin skill wording. CONTRIBUTING.md gains the
procedure; CLAUDE.md lists the command with its frontier-release cadence.

scripts/prompt-audit-manifest.ts

@@ -0,0 +1,114 @@
+#!/usr/bin/env bun
+/**
+ * Prompt-audit manifest: the files a contributor feeds to Anthropic's
+ * `/claude-api prompt-audit` (a Claude Code skill, run in your own Claude Code
+ * session) at each frontier-model release, cut into slices small enough for
+ * one audit pass each. Procedure: CONTRIBUTING.md "Prompt audit at each
+ * frontier-model release".
+ *
+ * Slices, in order: shared instructions every skill reads (CLAUDE.md, model
+ * overlays, preamble resolvers), the other resolvers, the skill templates
+ * (a skill's SKILL.md.tmpl and sections stay in one slice), the code that
+ * builds model requests, and the tests that pin skill wording (they read a
+ * template, skill or resolver and assert a literal of 40+ characters).
+ *
+ * Usage: bun run audit:manifest [--json] [--budget-kb <n>]
+ */
+import { readdirSync, readFileSync, statSync } from 'node:fs';
+import { join, relative, resolve } from 'node:path';
+
+const ROOT = resolve(import.meta.dir, '..');
+const DEFAULT_BUDGET_KB = 200;
+
+export interface AuditSlice { id: string; group: string; files: string[]; bytes: number }
+
+function walk(dir: string, keep: (rel: string) => boolean): string[] {
+  const out: string[] = [];
+  const visit = (d: string) => {
+    for (const entry of readdirSync(d, { withFileTypes: true })) {
+      const p = join(d, entry.name);
+      const rel = relative(ROOT, p);
+      if (entry.isDirectory()) {
+        if (!entry.name.startsWith('.') && entry.name !== 'node_modules') visit(p);
+      } else if (keep(rel)) {
+        out.push(rel);
+      }
+    }
+  };
+  visit(dir);
+  return out.sort();
+}
+
+const size = (rel: string) => statSync(join(ROOT, rel)).size;
+const read = (rel: string) => readFileSync(join(ROOT, rel), 'utf8');
+
+/** Pack units (each a list of files that must stay together) into slices under the budget. */
+function pack(group: string, units: string[][], budget: number): Omit<AuditSlice, 'id'>[] {
+  const slices: Omit<AuditSlice, 'id'>[] = [];
+  let current: Omit<AuditSlice, 'id'> | null = null;
+  for (const unit of units) {
+    const bytes = unit.reduce((sum, f) => sum + size(f), 0);
+    if (!current || (current.bytes > 0 && current.bytes + bytes > budget)) {
+      current = { group, files: [], bytes: 0 };
+      slices.push(current);
+    }
+    current.files.push(...unit);
+    current.bytes += bytes;
+  }
+  return slices;
+}
+
+export function buildManifest(budgetKb = DEFAULT_BUDGET_KB): AuditSlice[] {
+  const budget = budgetKb * 1024;
+  const preamble = walk(join(ROOT, 'scripts/resolvers/preamble'), rel => rel.endsWith('.ts'));
+  const shared = ['CLAUDE.md', ...walk(join(ROOT, 'model-overlays'), rel => rel.endsWith('.md')), ...preamble];
+  const resolvers = walk(join(ROOT, 'scripts/resolvers'), rel => rel.endsWith('.ts') && !preamble.includes(rel));
+
+  const templates = walk(ROOT, rel => rel.endsWith('.tmpl') && !rel.startsWith('test/'));
+  const bySkill = new Map<string, string[]>();
+  for (const rel of templates) {
+    const skill = rel.includes('/') ? rel.split('/')[0] : '(root)';
+    bySkill.set(skill, [...(bySkill.get(skill) ?? []), rel]);
+  }
+
+  const requestCode = [...walk(join(ROOT, 'lib'), rel => rel.endsWith('.ts')),
+    ...walk(join(ROOT, 'design/src'), rel => rel.endsWith('.ts')),
+    ...walk(join(ROOT, 'test/helpers'), rel => rel.endsWith('.ts'))]
+    .filter(rel => /api\.anthropic\.com|api\.openai\.com|\/v1\/messages|messages\.create|responses\.create/.test(read(rel)));
+
+  const pinningTests = walk(join(ROOT, 'test'), rel => /^test\/[^/]+\.test\.ts$/.test(rel))
+    .filter(rel => {
+      const src = read(rel);
+      return /SKILL\.md|\.md\.tmpl|scripts\/resolvers|model-overlays/.test(src) && /\.(toContain|toMatch)\((['"`])[^'"`]{40,}/.test(src);
+    });
+
+  const slices = [
+    ...pack('shared instructions', [shared], Infinity),
+    ...pack('resolvers', resolvers.map(f => [f]), budget),
+    ...pack('skill templates', [...bySkill.values()], budget),
+    ...pack('model-request code', requestCode.map(f => [f]), budget),
+    ...pack('tests that pin skill wording', pinningTests.map(f => [f]), budget),
+  ];
+  return slices.map((slice, i) => ({ id: `s${String(i + 1).padStart(2, '0')}`, ...slice }));
+}
+
+if (import.meta.main) {
+  const args = process.argv.slice(2);
+  const budgetArg = args.indexOf('--budget-kb');
+  const budgetKb = budgetArg >= 0 ? Number(args[budgetArg + 1]) : DEFAULT_BUDGET_KB;
+  if (!Number.isFinite(budgetKb) || budgetKb <= 0) {
+    console.error('--budget-kb needs a positive number of kilobytes');
+    process.exit(2);
+  }
+  const manifest = buildManifest(budgetKb);
+  if (args.includes('--json')) {
+    console.log(JSON.stringify(manifest, null, 2));
+  } else {
+    const files = manifest.reduce((n, s) => n + s.files.length, 0);
+    console.log(`Prompt-audit manifest: ${manifest.length} slices, ${files} files. Run /claude-api prompt-audit in Claude Code on one slice at a time (CONTRIBUTING.md).`);
+    for (const slice of manifest) {
+      console.log(`\n## ${slice.id} ${slice.group} (${slice.files.length} files, ${Math.round(slice.bytes / 1024)} KB)`);
+      for (const file of slice.files) console.log(file);
+    }
+  }
+}