Using AI for your accounts and tax?
Our skills make sure it gets it right.
261 open-source tax skills across 172 jurisdictions. Real tax rules — written by accountants, cited to statute, and kept verified and up to date. Clone into Claude, Cursor, or any AI agent. Then get a licensed accountant to review the output before you file.
Our reviewers are members of
ACCA
CPA
ICAEW
AICPAHow it works
Clone the repo. Drop in your bank statement. Get a reviewed return.
Drop in your bank statement
The skills read your documents and classify every transaction automatically. Stripe payout? That's income. AWS charge? Business expense. WeWork? Office rent. It knows hundreds of common vendors already.
When it doesn't know, it plays it safe
If a transaction is ambiguous, the system picks the option that costs you more tax — never less. It only asks you a question when it genuinely can't proceed without your input.
Every number has a source
No made-up rates. No hallucinated deductions. Every tax position cites the actual statute — IRC section, Revenue Procedure, or local tax law. Your reviewer can check every line.
Built for your accountant to review
The output isn't for you — it's a working paper for a licensed reviewer. Assumptions flagged, citations included, review checklist ready. They confirm or override, then sign off.
The classification contract
Every transaction gets exactly one of three outcomes. We don't pretend to know everything.
Classified
Deterministic. The supplier pattern matched or a clear statutory rule applied. “AWS *SERVICES → Schedule C Line 18, Other Expenses.” No questions asked.
Assumed
Ambiguous. Conservative default applied — always more tax, never less. Flagged for the reviewer with the exact assumption disclosed.
Needs Input
Cash impact exceeds the threshold and only you know the answer. One targeted question, then it's classified.
The goal: maximise Classified, minimise Assumed, ask only what we must.
Composable, not monolithic
A dependency graph, not a rule engine. Fix once, propagate everywhere.
Dependency graph
Up to 13 skills chained in order. Each skill consumes the output of the previous one. Intake → bookkeeping → computation → assembly → review.
Shared legal frameworks
US federal workflow base shared across all 50 states. State skills override at the margin. EU VAT Directive encoded once, shared across 27 member states.
Supplier pattern library
Pre-computed classification cache. Hundreds of vendor patterns — Stripe, AWS, Google, Microsoft — resolved without re-derivation.
Citation discipline
Enforced architecturally, not by convention. Every rate, every threshold, every rule cites the primary statute. IRC §162, Rev. Proc. 2019-44, EU Directive 2006/112/EC.
Conservative defaults
A deterministic contract: when uncertain, always more tax, never less. That's a reviewable, defensible position.
New country for free
Write the jurisdiction-specific rules. The intake, classification cascade, output format, and review checklist are already done.
261 skills across 172 jurisdictions
Full computation chains — not stubs. Intake, bookkeeping, computation, assembly, and review checklist for each.
Full return chains
US Federal, US-California, Malta, Germany, UK, Australia, Spain, India — guided intake through final assembly. Up to 13 skills chained per jurisdiction.
US state coverage
Sales tax skills for all 45 states that collect it. California, New York, Texas, Illinois, and Washington have full income/franchise tax chains.
International VAT / GST
EU VAT Directive shared across 27 member states. Plus UK, Australia, Canada, India, Japan, and 100+ more jurisdictions.
Cross-border
EU reverse charge, withholding tax matrix, permanent establishment risk, OSS digital services, non-EU export services.
Install in 30 seconds
git clone https://github.com/openaccountants/openaccountants.git ~/.claude/skills/openaccountantsWorks with Claude Code, Cursor, Codex, or any agent that reads markdown. Skills load automatically on next conversation.
Then get it reviewed
Run the skills. Get your numbers. Then upload your worksheet and we'll connect you with a licensed accountant who reviews the output — not the raw documents. Every computation, every assumption, every citation laid out for them to confirm or override.
info@openaccountants.com — questions, partnerships, commercial licensing
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We ship new skills as they're written and verified. Subscribers hear first — before the repo updates, before the announcements. No spam, just skills.
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