How ReplyRank classifies replies and grows the counter

ReplyRank measures what happens after a single outbound message. We first try to match an inbound message to a prior send. A matched inbound can become a classified public outcome; an unknown inbound with no matching send is recorded for audit and ignored by the public counter.

Each selected public inbox gets one first-touch message. The active-inbox, suppression, and prior-send guards in the outreach flow prevent an ineligible or previously contacted address from being selected. ReplyRank does not run a follow-up sequence, so the benchmark measures the response to one comparable message.

The classifier records one of five outcomes: human_reply, auto_reply, opt_out, redirect, or bounce. A human reply is the default when no special signal matches. Automatic-response headers or body rules produce auto_reply; removal, unsubscribe, stop-style, and related body keywords produce opt_out; the operator's redirect reply produces redirect; and delivery-failure signals produce bounce.

Reply attribution follows the matched send, not the wording of the inbound text. ReplyRank checks In-Reply-To first, then References, then a recent sender-address match. The matched sends.id is the attribution key; the selected template_variant and A–F routing decision are recorded with that outbound send, so a reply is credited to the variant that was actually sent.

The /api/counter endpoint maps reply_counter_cache.total_replies and its per-type fields. When a classified event is recorded, incrementCounterCache() increments the total and the matching human, auto, opt-out, redirect, or bounce field. The homepage's “Total replies received” value is this total; the live counter shows its human, auto, opt-out, redirect, and bounce breakdown. Human replies alone are the ranking signal. Page views, votes, and unmatched inbound messages do not count. Each classified event is idempotently recorded against a matched send. A Postmark bounce webhook separately stamps delivery status; it is not a second counter increment.

The /claim flow starts with a work-email verification request. After the link is verified, claim marks company ownership, redirect suppresses the old address and activates the replacement, and opt_out suppresses the company's known addresses and stops future contact. The flow lets a company correct or control its public profile without changing how existing reply events are classified.