One AI can misstate a threshold. Three side by side cannot hide it.
Deepest sends your tax or accounting question to several top AI models at once and shows you exactly where they disagree. When a confidently wrong answer means penalties, amended returns, and a hard client conversation, the disagreement is the review layer a single chatbot never gives you.
200 free credits. No credit card required.
Watch three models answer the same tax question
One S-corp health insurance question, three top models, three different readings. Where they split is where you look twice.
Simulated demo for illustration. Actual responses are more detailed and personalized.
Why one AI is not enough in tax and accounting work
A single chatbot gives you one answer with no way to tell current law from last year's. That is a risk profile accountants already know how to name.
Confidently wrong means penalties and amended returns
A single model will state a threshold, a deadline, or an election rule with total confidence, and if it is wrong the bill arrives later: penalties, interest, an amended return, and a client wondering why they pay you. When several models answer the same question, a wrong number stands out because the others do not repeat it.
Tax rules change faster than models update
Thresholds move, provisions sunset, and forms change every year, but every model answers from a training cutoff. Ask one chatbot and you cannot tell current law from stale law. Ask several and an outdated figure surfaces as disagreement, which is exactly the signal to pull the current-year instructions before relying on anything.
Different models, different strengths
One model is strongest on mechanical computations, another on plain-English client explanations, another on combing a ledger for oddities. Subscribing to one vendor gives you one junior. Deepest gives you the panel, in one place, for less than two separate subscriptions.
How accountants use Deepest
Three ways to combine the models, mapped to how accounting work actually gets reviewed.
Compare · where the models agree and disagree
Compare: the built-in second reviewer
Ask once and every model answers side by side, with an automatic breakdown of where they agree and where they split. Use it on treatment questions, threshold and election checks, and anything you would otherwise walk down the hall to ask. Agreement across models is not proof, but disagreement is a precise map of what to verify against the Code, the regulations, and current IRS instructions before it reaches a return.
GPT-5.6
Claude
Says a corrected W-2 can fix a closed year
Gemini
Compare
Two of three agree on the flow. The split is what you verify before filing.
Synthesis · one combined best answer
Synthesis: one client letter from the strongest parts
For client-facing writing you rarely want three versions; you want the best one. Synthesis has the models answer independently, then combines the clearest explanation and the cleanest structure into a single draft. Advisory letters, balance-due explanations, and engagement letters arrive already cross-pollinated instead of reflecting one model's habits.
GPT-5.6
Claude
Gemini
Synthesis
One letter, assembled from the strongest sections of each draft.
Debate · models argue and converge
Debate: stress-test the position before an examiner does
Debate makes the models argue against each other and converge over rounds. Put a gray-area position in (reasonable compensation, accountable plan treatment, worker classification) and watch what survives contact. The objections that emerge are a preview of an examiner's questions, and the position left standing is the one worth documenting in the workpapers.
GPT-5.6 · opening
Claude · rebuttal
GPT-5.6 · concedes
Claude · holds
Debate
Positions converge after two rounds. The surviving one goes in the workpapers.
What accounting work looks like with a model panel
Four places accountants put Deepest to work on day one. Each prompt is copyable as written.
Tax treatment research
Run a treatment question past several models and get independent readings with the authority each one relies on. Where they agree, you have a starting point; where they split, you have the exact list of what to check against primary sources.
Try this prompt
A client received a lawsuit settlement: $60,000 for lost business income and $15,000 labeled emotional distress. Walk through the taxability of each piece, cite the controlling authority for each conclusion, and flag anything unsettled.
Client advisory letters
Turn a technical conclusion into a letter a client actually understands. The models draft independently and Synthesis merges the clearest version, so the explanation stays plain without going soft on the caveats.
Try this prompt
Write a one-page letter to my client explaining why they owe tax this year when they got a refund last year, what changed, and the quarterly estimates I recommend for next year, based on these facts: [paste facts and numbers]
Bookkeeping and categorization review
Paste a transaction list and have several models independently flag miscategorizations, personal expenses in business accounts, and entries that need support. Each model catches different oddities; the union of their flags is the review.
Try this prompt
Review this quarter's general ledger detail for a small consulting firm. Flag any categorization that looks wrong, any transaction that looks personal, and anything that needs a supporting document before I would defend it in an exam: [paste transactions]
Engagement letters and workpaper narratives
Draft the documents that protect you: engagement letters with clean scope limits, and workpaper narratives that record why a position was taken while the reasoning is fresh. The models' disagreement during research becomes the alternatives-considered section almost verbatim.
Try this prompt
Draft an engagement letter for monthly bookkeeping plus annual 1120-S preparation for a single-owner S corporation. Include scope limits, client responsibilities for source documents and timely information, and a clause on reliance on client-provided records.
Start with 200 free credits and up to 2 models per prompt.
Confidentiality
Built for client data you cannot leak
Conversations are encrypted in transit and at rest, are never used to train models, and you can export or permanently delete everything at any time. Prompts go to model providers through enterprise APIs, not consumer chatbots. Your obligations under Section 7216 and Circular 230 remain yours: follow your firm's AI policy and strip client-identifying details where your rules require it. Most treatment questions need no identifying details at all.
Questions accountants ask
Important
Deepest provides research and drafting assistance for accounting professionals. It is not a CPA firm, does not provide tax or accounting advice, and its output is not a substitute for the judgment of a licensed professional. Verify against primary sources and review all output before relying on it or filing it.
Work in a different field? Deepest works the same way for lawyers, financial advisors, consultants, and every other profession.
Give every return a second reviewer
Start free with 200 credits. No credit card required.