For developers
Stop your AI guessing at tax law. Give it verified rules instead.
A Loyola University study found chatbots answer tax questions incorrectly two-thirds of the time. The fix isn't a warning label — it's giving the model verified rules to read. 1000 research-verified tax skills across 193 jurisdictions, works with Claude, ChatGPT, Cursor, Windsurf and any MCP-compatible agent.
Just want your own AI to use this — not build on it? Install the connector in two minutes →
Fastest: one command
Skip the clone. The CLI auto-detects your agent (Claude Code, Cursor, Codex) and installs only the jurisdiction you ask for — not all 1000.
e.g. npx openaccountants add malta, add US-CA. For live tools, wire up the MCP server with npx openaccountants connect. View on npm →
On Claude Code? Install the plugin instead
Auto-connects the hosted MCP server and adds a /openaccountants command:
Connect your AI agent via MCP
Your agent gets instant access to 1000 verified tax skills across 193 jurisdictions. Three tools, one prompt — no API key needed.
Just want to install it into Claude.ai / ChatGPT / Cursor / Windsurf? Go to the install page →
claude mcp add --transport http openaccountants https://www.openaccountants.com/api/mcp
list_skills
Browse all published skills. Filter by jurisdiction (US, MT, DE, etc.) or category.
get_skill
Fetch the full verified markdown for a skill — rates, thresholds, law references, computation steps.
get_skill_sections
Get parsed sections for step-by-step rule application to a specific tax scenario.
skill-review
Prompt that loads a skill and applies every rule to a taxpayer scenario, flagging items for accountant review.
Why a skill, not a naked LLM
Cited to statute
Every threshold, rate, and rule references the section, regulation, or revenue procedure it comes from. Easy to verify, easy to defend.
Verified by accountants
Skills in the verified tier are reviewed section-by-section by a licensed practitioner in the relevant jurisdiction. No vibes. No hallucinated numbers.
Year-dated
Skills declare the tax year they apply to and the date they were last verified. The agent surfaces both, so the next reader knows what they're looking at.
Three steps
Clone the skill
Pick the skill that matches your jurisdiction and situation (e.g. us-sole-prop-bookkeeping). Drop it into your agent's context. It works with any AI agent that reads markdown.
Run the computation
Feed the agent your bank statements, invoices, or bookkeeping export. The skill produces a working paper with the computation, assumptions, citations, and a self-check checklist.
Get a licensed accountant to review it
Share the working paper with a verified CPA, EA, or Chartered Accountant in your jurisdiction. They check the numbers and flag anything that needs fixing before you file.
Contribute
The skills are open source — clone them, run them, build with them. That's what they're for.
If you spot an error, submit a PR. If a jurisdiction is missing, write the skill. Every contribution is reviewed by a licensed accountant before it goes live.
The skills are the knowledge. Developers write and maintain them. Accountants verify the rules.
1000 skills across 193 jurisdictions
Free and open source. AGPL-3.0, with a commercial licence available. Contributions welcome — fork the skill, propose a change, get it merged once an accountant in that jurisdiction verifies it.