Add fire-and-forget Discord notifications for monitoring

New src/lib/notify.js posts to Discord webhooks (via env vars) on agent
creation, outbound email, and errors. Fully async — no await, no
latency impact on API requests. Silently skipped when env vars are unset.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: plc

src/lib/errors.js

@@ -11,6 +11,7 @@
  */
 
 const { pool } = require('../db');
+const { notify } = require('./notify');
 
 /**
  * Log an error to the error_log table. Never throws — falls back to console.error.
@@ -28,6 +29,7 @@ async function logError(err, ctx = {}) {
 
   // Always log to console too
   console.error(ctx.route || 'Error:', message);
+  notify('error', { route: ctx.route || 'unknown', message, agent_id: ctx.agent_id || 'n/a' });
 
   try {
     await pool.query(

src/lib/notify.js

@@ -0,0 +1,47 @@
+/**
+ * Fire-and-forget Discord webhook notifications for internal monitoring.
+ *
+ * Usage:
+ *   const { notify } = require('../lib/notify');
+ *   notify('agent_created', { agent_id: 'agt_xxx', name: 'My Agent' });
+ *
+ * Env vars (optional — if not set, the notification is silently skipped):
+ *   DISCORD_WEBHOOK_AGENT_CREATED
+ *   DISCORD_WEBHOOK_EMAIL_SENT
+ *   DISCORD_WEBHOOK_ERROR
+ */
+
+const CHANNELS = {
+  agent_created: 'DISCORD_WEBHOOK_AGENT_CREATED',
+  email_sent: 'DISCORD_WEBHOOK_EMAIL_SENT',
+  error: 'DISCORD_WEBHOOK_ERROR',
+};
+
+/**
+ * Post a notification to Discord. Never blocks, never throws.
+ *
+ * @param {'agent_created'|'email_sent'|'error'} event
+ * @param {object} data — included in the Discord message
+ */
+function notify(event, data = {}) {
+  const envKey = CHANNELS[event];
+  if (!envKey) return;
+
+  const url = process.env[envKey];
+  if (!url) return;
+
+  const lines = Object.entries(data)
+    .map(([k, v]) => `**${k}:** ${v}`)
+    .join('\n');
+
+  const content = `[${event}] ${new Date().toISOString()}\n${lines}`;
+
+  // Fire and forget — no await, no .then()
+  fetch(url, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ content: content.slice(0, 2000) }),
+  }).catch(() => {}); // swallow silently
+}
+
+module.exports = { notify };

src/lib/outbound.js

@@ -16,6 +16,7 @@
 
 const { default: ical } = require('ical-generator');
 const { pool } = require('../db');
+const { notify } = require('./notify');
 
 let postmarkClient;
 
@@ -82,6 +83,7 @@ async function sendViaSmtp(smtpConfig, params) {
   }
 
   const info = await transporter.sendMail(mailOpts);
+  notify('email_sent', { to: params.to, subject: params.subject, via: params.smtpConfig ? 'agent_smtp' : 'postmark' });
   return { sent: true, messageId: info.messageId };
 }
 

src/routes/agents.js

@@ -17,6 +17,7 @@ const { pool } = require('../db');
 const { agentId, apiKey } = require('../lib/ids');
 const { hashKey } = require('../lib/keys');
 const { logError } = require('../lib/errors');
+const { notify } = require('../lib/notify');
 const auth = require('../middleware/auth');
 
 const router = Router();
@@ -78,6 +79,8 @@ router.post('/', async (req, res) => {
     if (name) response.name = name;
     if (description) response.description = description;
 
+    notify('agent_created', { agent_id: id, name: name || '(unnamed)' });
+
     res.status(201).json(response);
   } catch (err) {
     await logError(err, { route: 'POST /agents', method: 'POST' });