Cost cap
AI Feature Cost Estimator
Size the monthly bill for an LLM feature before you build it. Requests, tokens, and rates in — cost per request, monthly, and annual out.
OpenTools
Small tools for shipping AI features
The same disciplines the practice runs on — a cost cap before you build, an eval set sized properly — as widgets you can use right now. They run entirely in your browser. No login, no tracking, no email wall.
Pick a tool
Eval harness
Eval Set Sizer
How many golden examples do you actually need? Pick a target accuracy, a margin of error, and a confidence level — get the sample size.
OpenHouse style
Prose Voice Linter
Paste a draft. It flags the banned words, exclamation points, and passive voice, then checks the short-declarative rhythm — the exact house rules behind Signal and Crafting.
OpenDecision-first
A/B Test Calculator
Drop in visitors and conversions for two variants to see lift, a p-value, and whether the result is real. Plus a planner for how many you need before you start.
OpenMore coming
These are the first two. If there’s a calculation you keep redoing in a spreadsheet, tell me — it might be the next one.