AI and Automation

AI Reply Classification

Bulko team May 9, 2026 4 min read

When your email campaign runs through 5-10 SMTP accounts, replies are returned to each of these inboxes. Without automation, you need to open 10 inboxes and manually sort hundreds of emails — which is a lead, which is a question, which is a bounce, which is an auto-reply.

Bulko automatically retrieves all replies via IMAP into a single dashboard and tags each email using an AI classifier.

5 Categories

  1. Positive — interested, wants to learn more, ready for the next step (call, demo, further conversation)
  2. Negative — not interested, not now, refusal. Doesn't mean forever, but the current outreach is closed
  3. Question — needs details, clarification, an answer to a specific question. Often turns into Positive after an answer
  4. Bounce — automatic message from the mail system about non-delivery (550, 553 codes)
  5. Auto-reply — out-of-office, vacation, holiday automatic message

Each classification comes with a confidence score from 0 to 1 — how confident the AI is. If the score is < 0.7, the email goes into the "manual_review" category, and you decide yourself.

What this gives in practice

For 1000 sent emails with a reply rate of 3%, you get 30 replies. Of these:

  • ~5-10 positive (your leads)
  • ~10-15 negative (exclude from further mailings)
  • ~5-7 questions (your answer is needed — these are potential positives after clarifications)
  • ~3-5 auto-reply (reply in 1-2 weeks)

Without AI classification, you spend 30-40 minutes sorting 30 emails. With AI — you open the dashboard and immediately see 5-10 positives in a separate list. The time savings are radical.

Accuracy

Based on real data, Bulko's accuracy in classifying positive/negative replies is around 92-95%. Question and auto-reply are classified with an accuracy of 88-92% — it's more complex there because the expressions are ambiguous. If the confidence is < 0.7, the email goes to manual review — this is ~5-8% of all replies.

Follow-up by trigger

Automatic follow-up works based on the classification: positive replies receive a second email with selling details after N hours. Negative replies never receive a follow-up. You can configure questions manually.

Details in the article about spintax and in the "Replies" dashboard.

Didn't find the answer?

Write to support and describe your case. We will help you set it up.

[email protected]