.chipset/state/mail/{agent-id}/{timestamp}-{from-agent}.json

.chipset/state/mail/polecat-alpha/2026-03-05T10-30-00Z-mayor-a1b2c.json
.chipset/state/mail/polecat-alpha/2026-03-05T10-31-00Z-witness-d3e4f.json
.chipset/state/mail/mayor-a1b2c/2026-03-05T10-32-00Z-polecat-alpha.json

{
  "from": "mayor-a1b2c",
  "to": "polecat-alpha",
  "type": "work_assignment",
  "subject": "Bead gt-abc12 assigned to your rig",
  "body": "Implement the auth middleware as specified in the convoy plan. Priority P1.",
  "timestamp": "2026-03-05T10:30:00Z",
  "read": false,
  "priority": "normal"
}

async function sendMail(message: MailMessage): Promise<void> {
  const mailDir = join(stateDir, 'mail', message.to);
  await mkdir(mailDir, { recursive: true });

  const safestamp = message.timestamp.replace(/:/g, '-');
  const filename = `${safestamp}-${message.from}.json`;
  const filePath = join(mailDir, filename);

  const content = serializeSorted(message);
  const tmpPath = join(mailDir, '.msg.tmp');

  const fd = await open(tmpPath, 'w');
  try {
    await fd.writeFile(content, 'utf-8');
    await fd.sync();
  } finally {
    await fd.close();
  }
  await rename(tmpPath, filePath);
}

async function checkMail(agentId: string): Promise<MailMessage[]> {
  const mailDir = join(stateDir, 'mail', agentId);
  let files: string[];
  try {
    files = (await readdir(mailDir)).filter(f => f.endsWith('.json')).sort();
  } catch {
    return []; // No mailbox yet
  }

  const messages: MailMessage[] = [];
  for (const file of files) {
    const msg = await readJson<MailMessage>(join(mailDir, file));
    if (msg) messages.push(msg);
  }
  return messages;
}

const unread = (await checkMail(agentId)).filter(m => !m.read);

async function markRead(agentId: string, filename: string): Promise<void> {
  const filePath = join(stateDir, 'mail', agentId, filename);
  const msg = await readJson<MailMessage>(filePath);
  if (!msg || msg.read) return;

  msg.read = true;
  await atomicWrite(filePath, serializeSorted(msg));
}

.chipset/state/mail/{agent-id}/archive/{filename}

async function archiveOldMail(agentId: string): Promise<number> {
  const mailDir = join(stateDir, 'mail', agentId);
  const archiveDir = join(mailDir, 'archive');
  const cutoff = Date.now() - 24 * 60 * 60 * 1000;
  let archived = 0;

  const files = (await readdir(mailDir)).filter(f => f.endsWith('.json'));
  for (const file of files) {
    const tsStr = file.split('-').slice(0, 3).join('-').replace(/T/, 'T');
    const fileTime = new Date(tsStr).getTime();
    if (fileTime < cutoff) {
      await mkdir(archiveDir, { recursive: true });
      await rename(join(mailDir, file), join(archiveDir, file));
      archived++;
    }
  }
  return archived;
}