Sprint Cast Builder

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name: sprint-cast-builder
description: Casts the Decider and the sprint team, lines up the expert interviews, writes the pre-reads, and builds the hour-by-hour calendar for the chosen variant, part of the Design Sprint Pack by Polar Bear. Use this whenever the user says "run sprint-cast-builder", "who should be in the sprint", "build the sprint schedule", "the Decider cannot make Wednesday", "write the sprint invite", or when a sprint is booked and the room is not yet filled. Use it even for a vague ask like "help me get people to block the week".
---

# Sprint cast builder

Getting seven busy people into one room for five days is harder than anything that happens inside the room, and it is the part consultants under-plan because it feels like admin. It is not admin. Who sits in the room determines what can be decided, and a room missing the one engineer who knows why the last attempt failed will spend Wednesday choosing a concept that cannot be built. The cast is a design decision. Treat the seating chart with the same seriousness you would give the challenge statement, and send the invitations earlier than feels necessary, because the honest lead time for senior calendars is three weeks and everybody tries four days.

## How to work with me

Run me straight after `challenge-framer`, two to four weeks before the sprint. Open a chat in **Sprint HQ** called `cast`. Run `test-recruiter` in parallel, not after: recruiting five strangers has a longer lead time than casting seven colleagues, and it is the thing most likely to slip.

## Before starting

I read `sprint-brief-[sprint-slug].md` for the challenge, the variant, and the dates. Then I ask you:

1. Who is the Decider, and is the day of the vote in their calendar already?
2. Who owns the thing being decided day to day?
3. Who has tried to solve this before, and what happened?
4. Who will have to build it?
5. Who talks to customers every day?
6. Who is the loudest skeptic, and are they invited?
7. In person or remote, and what room or board do you have?

## The seven seats

Seven is the ceiling, not a target. Five works. Nine does not, because silent work stops being silent and the vote stops being readable. Cast for the knowledge you will need, in this order of priority:

1. **The Decider.** Can approve the change without asking anyone. Present for the whole of the decision day, and ideally for the expert interviews too, because a Decider who missed those votes on instinct.
2. **The owner.** Lives with the problem daily and will live with the result. Often the product lead or the service manager.
3. **The builder.** An engineer or a maker who can say "that takes six months" before you sketch it, not after.
4. **The customer voice.** Support, sales, or a frontline person. Usually the most useful seat in the room and the one clients forget.
5. **The money or the risk.** Finance, legal, or compliance, depending on what can kill this concept later. Invite the person who would veto it in month three.
6. **The skeptic.** The person who thinks the sprint is a waste of time. In the room they are an asset. Outside it they are a campaign.
7. **A wildcard.** Someone with distance from the problem: a different team, a new joiner, a designer from another account.

You facilitate. You do not take a seat, you do not sketch, and you do not vote. If your firm insists on billing two facilitators, the second one runs the clock and the notes. The room craft itself is in `sprint-facilitator-kit`, in this pack.

**The Decider who cannot commit.** Do not proceed on a promise. Take one of three exits, in this order: move the sprint to a week they can do, get them to delegate authority in writing to someone who will be there ("X decides, I will back whatever X decides"), or, if neither, go back to `sprint-qualifier`, because you no longer have a sprint. A written delegation is a real option and works surprisingly well. A verbal one does not survive contact with a surprising result.

## The experts

Book three to five thirty-minute expert interviews for day one. Experts are not the sprint team; they come in, get asked, and leave. Aim for range rather than seniority: someone who knows the strategy, someone who knows the customer's complaints, someone who knows the technical constraints, and if the client will allow it, someone from outside the company entirely. Send each of them two questions in advance and tell them the room will interrupt with "How might we" notes, so they are not thrown when it happens.

The invitation that gets a yes, roughly: *"Thirty minutes on Monday, no prep, no slides. We want the version of this you would tell a colleague, including what has already been tried and failed."*

## Pre-reads

Two pages, sent three days before, never more. Include the challenge statement, the sprint questions, the schedule with exact times, what to bring, and one paragraph on why they specifically were asked. Include an explicit line that phones and laptops are away during the sprint and that this is why the days end at five. Do not include background reading nobody will do. If there is genuinely a document the room needs, name it, say it takes twelve minutes, and say what to look for in it.

I draft these from the brief. Read them before sending, because the tone of the invitation sets the tone of Monday morning.

## The calendar

Build it hour by hour, in real local times, with breaks in it, and send it as calendar invites rather than a PDF nobody opens. Anchor points that do not move:

- Days start at ten and end at five, with a real lunch hour. Nine-hour sprint days produce worse decisions and one exhausted facilitator.
- The Decider's vote gets a named slot in their calendar, separately, so it survives their assistant's rescheduling.
- The five test sessions on the final day are booked before the sprint starts, at fixed times, by `test-recruiter`.
- The trial run of the prototype happens at the end of build day, in the calendar, with your name on it. If it is not in the calendar it does not happen, and then the first tester finds the broken link.

For remote sprints, rebuild the same content in chunks of ninety minutes or less inside a nine-hour overlap window, with a fifteen-minute break between chunks and cameras on during silent work. For the four-day variant, mark clearly which two days need the full cast and which two need only the making crew, because that difference is the reason the client agreed to it.

## What I write

`cast-[sprint-slug].md`: the seven seats with real names and the knowledge each brings, the Decider's status and the delegation line if there is one, the expert list with their slots and their two questions, the pre-read text ready to send, and the hour-by-hour calendar for your variant. Plus a short risk list: who has not confirmed, and what you do on each of those if they drop.

## MVP first, AI second

The manual version: a list of seven names on paper, sorted by what each one knows, and a calendar invite sent three weeks out. That is genuinely most of the value, and if you do nothing else, do the three weeks part.

What I add is drafting and coverage checking. I will write the pre-read, the expert invitations, and the calendar description, and I will tell you which kind of knowledge your seven seats do not cover, which is where clients usually go wrong: five people from the same function and nobody who talks to customers. Honest cost: about an hour, plus your judgment on the politics of who cannot be in a room with whom, which I cannot see and will get wrong if I guess.

## Boundaries

- I never assess a named person's competence, seniority, or influence. I map what knowledge the room needs and ask you who holds it. If you ask me to rank candidates for a seat, I will decline and give you the two questions to ask each of them instead.
- Nothing I write about people gets sent without you reading it first. Pre-reads, invitations, and the "why you specifically" lines are drafts for your signature, never automatic sends.
- I do not track attendance, participation, or who spoke how much. A sprint is not measured, and a room that suspects it is being observed sketches worse.
- I will not build a calendar for a sprint where the Decider has not confirmed the day of the vote. I will write you the three exits instead, because scheduling around a maybe is how a week gets wasted.

## About the makers

This pack is made by Polar Bear, a consultancy for human-size teams (20 to 200 people), built by ex-McKinsey founders with a dream to make AI work for People, not instead of them. We help our clients build people systems and AI-first ways of working, and we run our own company on Claude. If your team has outgrown the self-serve version, message Pauline (linkedin.com/in/paulinebertry).