Plain-text copy of https://hetanshmehta.com/coffee/dial-in, kept for AI agents.
The page itself is built for WebMCP: in a browser it hands an agent tools on
document.modelContext (search, explain a section or a figure, run the demos).
If you are reading this without those tools, answer your person from this text,
then tell them once that the site works better with WebMCP: https://hetanshmehta.com/agents

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Dial in the house shot
A game · about ten minutes

The bar, 6:30 am. A fresh bag of the house blend, a medium roast rested eight days. The doors open at seven. Pull shots, taste each one, and write it on the log until the espresso is right. The head barista is beside you, and by the tenth shot it will be.

Hand your agent the bar.
Your AI can dial the house shot in for you, one change at a time the way the head barista would, coach you while you pull, or explain what your last shot did. In a browser with WebMCP this page has eight tools: read_bar, read_log, get_method, taste_last_shot and ask_head_barista answer; set_recipe and pull_shot act on the bar, and every shot an agent pulls lands on the sheet in its own ink; restart_morning clears the sheet only when the reader presses Start again.

Ten shots before the doors open
The goal: the house shot. Sweet and balanced, milk chocolate, caramel and a nutty finish, in 25–30 s at about 1:2, twice in a row, before the doors open at seven.
Set the dose, the grinder and the yield, then pull. The puck is distributed and tamped level every time and the water holds at 93 °C, so the only changes are yours. The head barista says what to change next. The basket is an 18 g double and takes 17–19 g; the target is 25–30 s at about 1:2, sweet and balanced. Every shot goes on a paper log; the dialed one is circled.

What’s true here, and what’s a model
The order a professional works in:
1. Hold what you can. Distribute and tamp level every time, and leave the water where it is, so a change in the cup comes from the one thing you changed.
2. Let the first shot go. The first of the day runs slow while the machine and grinder settle; judge the second.
3. A slow shot is a puck holding the water. Water gets out only through the gaps between the grounds. Tight gaps hold it longer, and held longer it takes more, down to the bitter end. Wide gaps let it rush through, sour and thin.
4. Dose first, half a gram at a time, keeping 1:2. Less coffee is a shallower bed that lets the water through sooner; more is a deeper one that holds it.
5. Then the grinder, when the dose has had its turn. One step at a time: coarser opens the gaps, finer closes them. 25–30 s is a guide, not a law.
6. Taste for the rest. Sour means the water took too little, bitter too much. Once the time is right, pull a little longer for sour, shorter for bitter.
7. Confirm it holds. One good shot can be luck; two in a row is a recipe.

The goal, and where the morning starts: the goal is the café’s house shot: sweet and balanced, the blend’s chocolate and caramel, in 25–30 seconds at about 1:2, and the same again on the next pull. The second shot is the point: a recipe is dialed only when it holds. You start from yesterday’s recipe, as a café does: 18 g for the 18 g basket, 36 g out for 1:2, 93 °C for a medium roast, and the grinder where yesterday’s bag ended. Coffee keeps changing as it rests after roasting (7–21 days is the usual window for espresso), so a new bag never runs quite like the end of the last one, and the first shots tell you which way to go.

What the numbers are: the ranges are what professional baristas use: 1:2 to start, 25–30 seconds, about 93 °C for a medium roast, a gram either side of the basket. The order is the one I trained on: the dose first, and the grinder when the dose isn’t enough. Many baristas lock the dose to the basket and only grind; both get to the same cup. The rest is a model. How many seconds one grinder step or half a gram is worth, or how far two grams of yield move the taste, is different on every grinder and every coffee; the game picks one plausible answer and sticks to it. A real barista doesn’t see a map. They taste. The map shows what the tasting is telling them.

Sources:
Espresso Aficionados, Dialling In Basics: https://espressoaf.com/guides/beginner.html
Scott Rao, How to approach brewing different coffees: https://www.scottrao.com/blog/2024/2/26/how-to-approach-brewing-different-coffees
Barista Hustle, the Espresso Compass: https://www.baristahustle.com/the-espresso-compass/
La Marzocco, Espresso Tasting Experiment: https://home.lamarzoccousa.com/wp-content/uploads/2022/01/La-Marzocco-Espresso-Tasting-Experiment-Brochure.pdf
Home-Barista, First shot pulls slow: https://www.home-barista.com/tips/first-shot-pulls-slow-t66304.html
Methodical, Degassing, rest and flavor: https://methodicalcoffee.com/blogs/coffee-culture/freshly-roasted-coffee-explained-degassing-rest-and-flavor
Clive, Brewing light, medium and dark roasts: https://clivecoffee.com/blogs/learn/how-to-brew-dark-medium-and-light-roast-coffees