Every AI system in a regulated workflow has two users: the operator who requests the output today, and the examiner who reviews it later — with subpoena-grade patience and no goodwill. Almost all AI product design serves the first user. The systems that reach core workflows will be the ones designed for the second.
Read →Research & announcements
Protocol releases, technical thinking, and updates from Arcus Labs
Almost there — check your inbox
We sent a confirmation link to finish your subscription. Click it and you’re all set.
The industry uses one word for two different things: the capability and the process. AI asks a model what it thinks; artificial reasoning defines how the system must think — as an explicit computation that records itself as it runs. Here is the distinction in full, what the term does not claim, and the falsifiable bet underneath it.
Read →
Every number an LLM produces is a prediction of what a number would look like. That's tolerable in a chatbot and disqualifying in a decision system. The engineering answer is deterministic tool-nodes — zero tokens, byte-reproducible — but the property that actually matters is authority: the model may cite the numbers, never recompute or override them.
Read →
Reg E’s error-resolution deadlines are absolute: 10 business days to investigate, 45 or 90 calendar days with provisional credit, no tolling for backlogs or turnover. Dispute volume has exploded with P2P fraud while investigation teams haven’t grown. The failure mode isn’t missing deadlines — it’s making them with investigations that can’t survive an exam.
Read →
The four-fifths rule is a fifty-year-old screening heuristic that AI decisioning has made load-bearing again. It is a tripwire, not a verdict — and both halves of that sentence matter. What the Adverse Impact Ratio measures, where practical and statistical significance diverge, and why the computation should never come from the model being tested.
Read →
A chatbot produces one reasoning event per interaction. An agent produces one per step — planning, tool selection, interpretation, revision — hundreds per task, invisible in the tool logs everyone mistakes for observability. The agent wave is a multiplication of exactly the thing enterprises never learned to govern.
Read →