It started with a habit I picked up while building in this space: running real transactions through the popular crypto tax tools and checking their answers against the actual on-chain evidence. A liquid staking exit would come back labeled as ordinary income. A bridge would come back as a taxable sale. Always confidently, never with any signal that the answer might be wrong. A visible error is fixable. An error behind a clean green checkmark is how bad returns get filed. So the engine has one rule at its core: never guess silently. Every classification returns the tax treatment, the reasoning in plain English, a confidence score, and an explicit review flag when the evidence does not support a verdict. For the person reviewing a client's year, "12 of these 4,000 transactions need a human" beats 4,000 unqualified answers. The build evolved in stages. First a rules library I maintained by hand. Then a pattern engine with multi-source consensus. Then AI adjudication with deterministic guardrails, meaning the model never overrides what the receipts and logs actually show. It now stands at 13,000+ verified rules across 80+ chains, and it compounds: every hard transaction it resolves becomes a rule the next lookup benefits from. Three ways to try it today: the Explorer (enter a transaction hash, get the treatment and the reasoning), the REST API and MCP server for your own app or agent, and a Chrome extension that shows verdicts inside the tax platforms accountants already work in. It's built for crypto tax practitioners and the developers building for them. Send me a transaction your current tool gets wrong and I'll run it.

CryptoTaxEdge

Crypto tax classification API for devs.

Crypto tax classification API for devs.