KoltrixPrimary, Other, Cold pitches, Newsletters, Updates: why five
Why Koltrix sorts mail into five fixed categories instead of dozens, what belongs in each one, how teams work through them, and where custom labels still fit.
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Five is a deliberately small number. It would be easy to offer a category for everything: investors, recruiters, vendors, press, receipts, alerts. Koltrix keeps five, because each one answers a single practical question: does this need a person's attention, and how soon?
Here's what each of the five categories is for, why a short list works better than a long one, and how custom labels fill in the details.
The problem with lots of categories
Every category you add creates a border with its neighbors, and borders are where sorting goes wrong. Is an email from a recruiter who is also a former customer "Recruiting" or "Customers"? Is a vendor's renewal notice "Vendors", "Billing" or "Updates"? A person hesitates on these. A model hesitates too, and when it guesses, someone on your team disagrees with the guess.
Many categories also cost attention. If your inbox has twelve tabs, you have twelve places to check, and the whole point of sorting was to check fewer places.
So the design goal was a set of buckets that are:
- Mutually exclusive, so most messages clearly belong in exactly one.
- Action-oriented, so each bucket implies how to treat what's inside it.
- Few enough to scan in a glance.
The five categories
Primary
Mail from real people that likely needs a reply or a decision: customers, partners, colleagues at other companies, investors, anyone you're in a conversation with. If you only had ten minutes today, this is where you'd spend them.
Primary is intentionally the default for anything ambiguous. If the AI isn't confident a human-written message belongs elsewhere, it stays here, because burying a real conversation is the expensive mistake.
Other
Human-written or one-off mail that's legitimate but lower priority: an event invitation, an introduction that doesn't need action yet, a community announcement, a message you'll want eventually but not this morning. It's the "real, but not urgent" pile.
Cold pitches
Unsolicited outreach: sales sequences, agency offers, link-building requests, "quick question" emails from people you've never dealt with who want to sell you something. Some are worth reading. Very few need a reply today. Separating them stops a dozen pitches from pushing a customer's question below the fold.
Newsletters
Content you subscribed to (or were subscribed to): industry newsletters, product blogs, digests, community roundups. You read these on your schedule, not the sender's.
Updates
Automated, transactional mail about accounts and systems: receipts, invoices, shipping confirmations, password resets, notifications from tools you use, calendar updates. Mostly reference material, occasionally important.
A quick reference
| Category | Typical sender | Usually needs | Check it |
|---|---|---|---|
| Primary | A person you have or want a conversation with | A reply or decision | First, several times a day |
| Other | A person or organization, low urgency | Reading, maybe later action | Daily |
| Cold pitches | Someone selling to you | Nothing, occasionally a reply | Weekly skim |
| Newsletters | Publications and lists | Reading when you choose | When you have time |
| Updates | Systems and tools | Filing; sometimes action | Scan daily for problems |
How a team uses them day to day
A simple rhythm works well:
- Work Primary first. Reply, decide or hand off everything there. This is where customers live.
- Scan Updates for problems. A failed payment, a security alert or an expiring certificate notice is automated but not ignorable. A quick scan catches these.
- Skim Other once a day.
- Leave Newsletters and Cold pitches for a scheduled moment, or let them sit. Nothing bad happens if you read them on Friday.
In a shared mailbox, this also gives the team a shared vocabulary. "Primary is clear" means the same thing to everyone.
Where the categories get it wrong
No classifier is perfect, and some situations are genuinely ambiguous:
- A customer writing from a personal address for the first time can look like a stranger.
- A real partner might send a newsletter-style announcement through a bulk email platform.
- A cold pitch might be disguised as a reply ("Re: our call").
- An automated notice might need urgent action.
When a message is in the wrong place, move it. Then, if it's a pattern from a known sender, add a rule so it lands correctly every time. That combination, AI for the fuzzy cases and rules for the cases you know, works better than either alone.
Where labels fit
Categories answer "how urgent is this kind of mail?" They don't answer "what is it about?" or "what state is it in?" That's what labels are for.
Koltrix lets you create your own labels and auto-label rules on top of the five categories. A practical split:
- Categories (fixed, AI-sorted): priority and type of sender.
- Labels (yours, rule-based or manual): topic, customer tier, workflow state.
For example, a Primary email might also carry Billing and Waiting on customer. An Updates email from your payment processor might get a Finance label by rule. The categories stay small and stable while labels carry everything specific to your business.
If you find yourself wishing for a sixth category, it's usually a label in disguise.
Why not let every team define its own categories?
It's a fair question. Every business is different, so why not let each team invent its own buckets? Two reasons.
First, custom categories tend to grow. A team starts with five, adds "Investors" after a fundraise, "Press" after a launch, and "Recruiting" during a hiring push. A year later there are fourteen, half of them overlap, and nobody remembers what "Partners-2" was for. Fixed categories resist that drift.
Second, a small fixed set means the sorting behaves the same way for everyone on the team, in every mailbox. A new hire learns the five once and can work in any shared mailbox on day one. The business-specific detail still exists; it just lives in labels, where it's easy to add, rename and retire without changing how the whole inbox is organized.
What sorting never does
Sorting moves mail between views. It's reversible, which is why it's a good job to hand to AI. Koltrix also summarizes threads and drafts replies, but drafts stay drafts: nothing is sent without a person clicking send.
Key takeaways
- Few, mutually exclusive categories sort more consistently than many overlapping ones.
- Primary holds real conversations and is the default when the AI is unsure.
- Other, Cold pitches, Newsletters and Updates each imply a different, lower level of attention.
- Work Primary first, scan Updates for problems, and batch the rest.
- Use labels and rules for topics, tiers and workflow states instead of asking for more categories.
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