Six things Latch does — and the constraints behind each one.

Latch builds a model of you in your first week — who you reply to, how fast, who you ignore, which phrases mean 'I need a decision' versus 'FYI'. After seven mornings of confirmations, it gets >95% of your inbox right.

Signals used: sender history, thread velocity, your last-30-days reply patterns, calendar proximity, explicit asks, deadline language. Not: subject-line keywords. We don't use them.

For every thread that needs a response, Latch writes a draft grounded in how you've actually replied to similar threads. Your phrasing. Your tone. Your sign-off. You edit a sentence and send.

Drafts are scoped to your account and trained on your sent-mail only. No cross-tenant learning. No fine-tuning on your data without your explicit opt-in.

Every morning, Latch sends one summary: the four threads that need you today, what each one is asking, and a one-tap link to the draft reply. That's it. No app to open. No badge count. No 'check Slack'.

You choose the delivery time and day-of-week pattern. Skipping weekends is the default. You can also pause Latch for a stretch — vacations, sprints, surgery, whatever.

Latch runs on Cloudflare Workers and Durable Objects. Your messages are processed at the closest edge node and never sit on a long-lived server. The model that knows you is a per-account Durable Object — isolated, encrypted, deletable in one click.

Threat model: assume the platform is breached. Per-account isolation means a breach exposes one inbox, not all of them. Encrypted at rest. Audit log of every read.

Confidence scores are visible on every triage decision. Below 70% confidence, Latch surfaces the thread anyway and asks. We'd rather waste 30 seconds of your time than archive something that mattered.

Confidence is calibrated, not vibes. We log the post-hoc outcome of every decision and re-fit weekly. The model drifts in your favor.

One click exports the model that learned you — your reply patterns, your priorities, your archive history. The DO is deleted. The mail-server connection is revoked. No 30-day grace period, no recovery dark patterns.

Export format: portable JSON. Re-importable into the open-source self-hosted build (coming v1.2).