Post
Your inbox has 42,000 unread emails.
Somewhere in there is the K-1 your client sent last Tuesday.
Post watches your firm's inbox, understands what's coming in, pulls the important content out, and sends it to the right place. Automatically.
The Problem
Information arrives faster than anyone can file it.
Documents vanish in threads
Clients forward W-2s buried in reply chains mixed with questions, small talk, and "here u go" messages. Documents get lost. Context evaporates.
Context dies in the inbox
When a client calls months later asking "why did you do X?", the answer died in an inbox somewhere. No one remembers the email. No one can find it fast enough.
Knowledge walks out the door
The senior partner knows every client's quirks. Who needs reminders, who sends photos of documents, who panics in Q4. When they retire, all of it disappears.
How It Works
Post in four steps
Every email passes through a pipeline built for accounting. Domain-aware classification that knows a 1099-NEC from a newsletter.
Identify
AI with accounting domain knowledge classifies every incoming email. Who sent it, what it is, and why it matters.
Extract
When documents arrive, AI pulls key fields. Form type, tax year, amounts, identifying details. Enough to know what it is without opening it.
Route
One-click routing to the right place in the Cairn suite. K-1s to Returns. Receipts to Receipts. IRS notices to Notices. Nothing gets lost.
Learn
Over time, Post builds profiles of how clients communicate. Who responds quickly, who needs reminders, who sends phone photos. That knowledge feeds into Contacts.
Incoming / Today
12 classifiedFW: Here's the K-1 from Chen Holdings partnership
FW: Got this from the IRS - what do I do??
here u go (attached: blurry phone photo)
Can we deduct the new office furniture if we bought it in December?
AI that knows accounting, not just email.
Post doesn't do generic sorting by importance. It understands that "here u go" with a blurry phone photo might be a W-2. It knows a forwarded chain from a client's banker probably contains financial documents. It recognizes an IRS CP2000 notice even when the client's subject line is just "help???"
Every classification carries routing context: this document goes to this app, for this client, matching this open request.
The Differentiator
Post sorts email. Then it learns people.
Over months and years, Post builds behavioral profiles from email patterns. The institutional knowledge a senior partner spent decades accumulating, built automatically.
Responds within 2 hours to document requests. Always CCs spouse on financial matters. Prefers phone photos over scans. Gets anxious in Q4. Shorter emails, more follow-ups.
Typically needs three reminders for document requests. Sends everything as forwarded chains, attachments buried in threads. Most responsive on Tuesdays. Business decisions involve their CFO, CC'd on 80% of financial correspondence.
Asks advisory-level questions frequently. Consistently early with documents, sends unprompted. Communication peaks around board meetings (quarterly). Professional tone, expects detailed responses.
When the founding partner retires, their 30 years of client knowledge doesn't walk out the door.
Post feeds behavioral intelligence directly into Cairn Contacts: communication patterns, response habits, document preferences, relationship signals. AI synthesizes it into client personality profiles that any team member can access instantly.
New hires don't start from scratch. They inherit decades of relationship context from day one. The firm's institutional knowledge lives in the system, not in someone's head.
Feeds into: Cairn Contacts AI client briefs, relationship intelligence, and client personality profiles. The richest data source in the Cairn integration network.
The Ecosystem
The front door to the entire Cairn suite.
Post sees everything coming in and knows where it should go. Every app in the suite gets smarter because Post feeds it context. And Post gets smarter because every app provides classification data back.
Tiered Processing
Not every email needs AI.
Post uses a four-tier pipeline that filters noise early and saves the heavy analysis for emails that actually matter.
Rule-Based Filtering
Spam, newsletters, auto-replies. Caught and discarded without touching AI.
Lightweight Classification
Quick pass sorts remaining email into signal vs. noise. Client vs. non-client.
Full AI Analysis
Accounting-domain classification for emails that matter. Document type, urgency, routing.
Document Extraction
Attached documents get key fields pulled: form type, tax year, amounts, identifiers.
Post watches. Post understands. Post routes.
Your team decides and acts.
Not an email client. Doesn't replace Gmail or Outlook.
Not an auto-responder. Never sends emails on behalf of the firm.
Not a practice management suite. Focused on intake intelligence, not workflow management.
Capabilities
What Post does
AI classification that knows accounting (tells a 1099 from a newsletter)
Extracts key fields from K-1s, W-2s, 1099s, bank statements, and receipts
One-click routing to Returns, Docs, Statements, Receipts, and Notices
Learns each client's communication patterns over time
Tiered processing pipeline, from rule-based filtering to full AI analysis
Gmail and Microsoft Outlook integration via OAuth
Feeds client profiles into Cairn Contacts automatically
Part of the Stack
Connects to every app in the suite
Post is the most connected app in the Cairn ecosystem. It consumes cross-app data and provides it back in equal measure.
Cairn Contacts
Sends communication patterns, response habits, and relationship signals into client profiles.
Cairn Returns
Routes tax documents (K-1s, W-2s, 1099s) to the correct filing.
Cairn Docs
Auto-fulfills open document requests when matching attachments arrive.
Cairn Statements
Matches forwarded bank statements to the correct client account.
Cairn Receipts
Routes receipt images and expense documents for categorization.
Cairn Notices
Routes IRS and state correspondence to the notice tracker.
We're building Post.
The most ambitious tool in the Cairn suite, and the one that ties everything together. We're onboarding firms individually to get this right.