The best AI coach for Intervals.icu: how to choose

Many tools in this space started the same way: a talented athlete-developer scratched their own itch and shared the result on the forum. It is the best origin story in software. It is also how products get abandoned when a job changes, a baby arrives, or the fun wears off. Before you hand a tool your training block, it is fair to ask who is behind it. Is anyone's livelihood attached to this thing still working in twelve months? Is there a company, a roadmap, someone who answers when sync breaks on the morning of your A-race?

In a hot market, tools start shipping fast in every direction. One adds a dashboard this week, another copies it the week after, sometimes down to the pixel. Speed looks impressive from a distance. Up close, a pile of features collected in a copy race rarely adds up to a product. Coherence is what you notice three months in, when the pieces either fit together or don't. A simple test: can the maker explain why the product works the way it does? A philosophy you could disagree with beats a changelog you can't keep up with.

Connecting a large language model to your Intervals.icu data takes an afternoon. Several tools in this space are exactly that, and say so openly. It is a cool capability. It is not coaching. Language models are excellent at conversation and explanation, and unreliable at arithmetic, consistency and multi-week planning constraints. A real coaching product uses code and algorithms where precision matters (load math, periodization rules, recovery baselines, guardrails) and lets the LLM do what LLMs are good at. If a tool's answer to "how does the plan engine work?" is "the AI figures it out", that is not an engine. That is a hope.

Here is the most honest research you can do in this ecosystem, and it costs nothing. Every one of these tools has a public thread on the Intervals.icu forum. Read the whole thread, not just the announcement post. Count two things: users reporting bugs, sync failures and broken plans, and users saying the tool changed their training. That ratio tells you more than any landing page. Do this for every tool on your shortlist. Ours too.

Some tools in this space have no interface at all; you coach yourself in a chat window. Others have collected so many panels and buttons that finding today's workout takes a manual. Neither is a crime, but it decides what your mornings look like. An AI coach you will actually follow needs an interface that makes the next step obvious. The test takes five seconds: open the tool. Do you know what you are doing today, and why?