Lesson 10 · Customer-Facing Craft
Discovery, Scoping & Demos That Land
The consulting half of the role: find the real problem behind the ask, write a scoping doc that survives contact with reality, demo like the meeting matters — and know when to say "don't build this."
Nine lessons of engineering, and here is the uncomfortable truth: the skill that most often decides an FDE interview — and an engagement — isn't any of it. Exponent's analysis of FDE interview loops names the single most common rejection reason: jumping to a solution in the decomposition round.1 The 1,000-posting market analysis found the skill profile shifting toward "a hybrid of technical depth and customer-discovery ability"3 — and recruiters say the translation half of that hybrid is the hardest of all four FDE competencies to find.2 This lesson trains the consulting half of the role: discovery, scoping, translation, demos — and the judgment call the whole course has been building toward.
First, honesty: there is no canonical playbook
Let's be straight about the ground we're standing on. As of mid-2026, no canonical FDE discovery methodology exists — the role is young and its literature is thin. What follows is a synthesis, clearly labeled as such: built from the Exponent interview analysis1, Palantir's founding discipline of identifying the most valuable thing to work on4, practitioner accounts of the engagement day-to-day5, and consulting-adjacent practice like Rob Fitzpatrick's The Mom Test — the standard text on asking customers questions that produce truth instead of politeness.7 Treat it as a strong default, not gospel — and expect to sharpen it against real customers.
Discovery: the ask is not the need
Every engagement starts with an ask: "we want an AI copilot", "we need a chatbot", "can you add RAG to our portal". The ask is a solution the customer has already imagined — and the founding FDE discipline is to treat it as evidence about the problem, not a spec.4 Your job in discovery is to walk the ask backwards to the pain that produced it: who hurts, doing what, how often, at what cost, and what happens if nothing changes. The Mom Test's core rules translate directly: ask about their life, not your idea; ask about specific past incidents, not hypothetical futures; and let them talk — the customer should hold the floor most of the meeting.7
| Instead of asking… | Ask… | What it surfaces |
|---|---|---|
| "Would an AI copilot help your team?" | "Walk me through the last time this went wrong." | A concrete incident with real steps, systems and people |
| "What features do you want?" | "Where does the time actually go in that workflow?" | The costliest step — often not the one in the ask |
| "Is data quality an issue?" | "Show me the actual data. Can I shadow someone for an hour?" | Ground truth — what people do, not what they report |
| "Any compliance concerns?" | "What would your regulator or legal team say if we shipped this?" | The blocker nobody volunteers until it kills the project |
| "Would you use this?" | "If this worked, what number changes, and who tracks it?" | The success metric — and whether anyone actually owns it |
Decomposition and the scoping doc
Discovery produces raw material; decomposition turns it into an engagement. Break the vague ask into a tree of concrete sub-problems, each small enough to ask three questions of: is it valuable, is it feasible, and — the AI-judgment question — is AI even the right tool for it? Interviewers run this exact exercise as a live round, and the failure mode is always the same: proposing an architecture before the problem is decomposed.1 The written artifact is the scoping doc — the document that converts a conversation into a commitment both sides can hold each other to:
| Section | What goes in it | Smell test |
|---|---|---|
| Problem decomposition | The ask, the underlying problems found in discovery, broken into a tree of sub-problems | Could a stakeholder point at the branch that hurts most? |
| Asked vs needed | What the customer asked for, what discovery showed they need, and the evidence for the gap | Is the gap backed by incidents and numbers, not vibes? |
| Success metrics | Eval-shaped, measurable targets per phase — the numbers your evals from Lesson 05 will track | Could you build the eval harness from this section alone? |
| Risks | Data access, compliance and privacy, adoption, model-failure modes — with an owner and mitigation each | Does it include the risk the customer didn't volunteer? |
| Phased plan | Smallest valuable phase first, with a go/no-go metric gating each next phase | Does phase one ship real value in weeks, not months? |
| Out of scope / not AI | What you are explicitly NOT building — including anything where AI is the wrong tool, with the reason | Is at least one "we recommend not using AI for X" line in it? |
Stakeholders and translation
An engagement has more than one customer. Map them early — sponsor (owns the budget and the "why"), end users (own adoption; the clinicians, agents, analysts who must actually change how they work), technical gatekeepers (own access to data and systems), and risk owners (legal, compliance, security — the quietest voices with the loudest veto). Each needs the same truth in a different language, and that skill — translation, trade-offs in non-technical words — is the one recruiters call the hardest of the four competencies to find.2 The pattern: never hand an executive a metric; hand them a decision. Not "our judge-scored faithfulness is 0.92" but: "about one summary in twelve still contains an error a clinician must catch, so we keep a human review step — we can shrink that number, and here's what each point of improvement costs." Metric → consequence → choice.
Demos that land: the meeting is the craft
Lesson 06 taught you to build the demo; this is the meeting craft. Demos that land share five habits. Their data, not yours — a mediocre demo on the customer's real tickets beats a slick one on synthetic data, because recognition is what creates belief. Their words — name the workflow exactly the way the users named it in discovery. One workflow, end to end — depth on the branch that hurts most, not a feature tour. Rehearse the failure — show one case the system gets wrong and how it's caught; the honesty buys more trust than the wins do, and it sets up the AI-judgment conversation. And end on a commitment — a demo lands when it converts into a named next step: these three users, this data access, this date. Remember what an FDE demo is for: unlike a solutions architect, you are not selling the recommendation — you're opening the door to production code on their infrastructure.6
Recommending against AI — and keeping the customer
This is the AI-judgment thread's home lesson. Models are persuasive when they're wrong2 — and so are roadmaps. Some of what discovery surfaces will be problems AI shouldn't touch: deterministic rules pretending to be judgment calls, workflows where one bad output is unrecoverable, automation of a step nobody actually spends time on. Saying so is a skill with a shape. Anchor in their goal: "you want fewer triage errors" — not "your idea is bad". Show the evidence: the eval numbers, the failure cases, the cost per correct outcome from Lesson 09. Offer the boring alternative: often a rules engine, a form redesign, or a reporting fix delivers the outcome for a tenth of the risk. Redirect, don't just refuse: pair every "not this" with the branch of the decomposition tree where AI does earn its keep. Customers don't fire the engineer who saved them from a failed pilot — in a market where roughly 95% of GenAI pilots show no measurable impact3, "we recommend not building this" is the cheapest credibility you will ever buy.
🧪 Practical steps: the discovery pack (~90 min)
This lab is conversation plus writing, not code. You'll run a simulated
discovery conversation against a role-played stakeholder — the Head of Clinical Ops at the
same fictional virtual-care provider your Lesson 11 capstone serves — then write the scoping
doc. The role-play prompt gives your AI assistant a stressed executive with a vague ask
("we want an AI copilot for our clinicians") and hidden real problems it will only reveal
under good questioning, including a compliance worry it won't volunteer at all unless probed.
Full instructions and the copyable role-play prompt are in
labs/0010-discovery-pack.md.
- Start the role-play — paste the stakeholder prompt from the lab file into a fresh chat with any AI assistant. It will play the Head of Clinical Ops and open with the vague copilot ask.
- Run discovery (~30 min) — use the question patterns from this lesson: last-time-it-went-wrong incidents, where the time goes, show-me-the-data, the regulator question, what-number-changes. Take notes as you go; don't propose solutions yet.
- Draw the decomposition tree — the ask at the root, the real problems you surfaced as branches, sub-problems as leaves, each tagged valuable / feasible / AI-appropriate.
- Write asked-vs-needed — one short section: what they asked for, what discovery showed they need, and the evidence for the gap.
- Write eval-shaped success metrics — measurable targets per phase that a Lesson 05 eval harness could actually track.
- Write risks and the phased plan — including the compliance risk (did you find it? Australian Privacy Act territory), each risk with an owner and mitigation, and a go/no-go metric gating each phase.
- Write the "not AI" line — at least one explicit "we recommend NOT using AI for X, because Y — instead do Z" recommendation, in non-technical language.
- Save the pack — transcript notes, tree, and scoping doc — to
D:\Projects\FDE-Portfolio\l10-discovery-pack\.
Feedback loop: bring the scoping doc back to me in chat with your discovery transcript, and I'll review it like the customer's steering committee would — did your questions earn the hidden problems, does the tree go deeper than the ask, would a non-technical sponsor understand every trade-off? This is the direct rehearsal for the Lesson 11 capstone engagement — the same fictional customer, for real this time — and it's tracked in the course's artifact tracker.
No chat here — this box replaces it. Copy the prompt into any AI assistant (Claude, ChatGPT, Gemini…), then paste your scoping doc (and discovery notes) after it.
You are a skeptical customer steering committee reviewing a Forward Deployed Engineer's discovery pack for a virtual-care provider. The pack contains: notes from a discovery conversation, a problem decomposition tree, an asked-vs-needed analysis, eval-shaped success metrics, risks (including compliance), a phased plan, and at least one "we recommend NOT using AI for X" recommendation. Grade each criterion as Strong / Adequate / Missing, with one sentence of evidence: - Quality of probing questions: the discovery notes show questions about specific past incidents, real data, and unvolunteered risks (especially compliance) — not hypothetical or leading questions that invite polite lies. - Decomposition depth: the tree goes at least two levels below the original ask, and each leaf is tagged for value, feasibility, and whether AI is the right tool — with at least one branch honestly ruled out. - Non-technical clarity of trade-offs: every metric and trade-off is translated into consequence-and-choice language a non-technical executive could act on, with no unexplained jargon. Be adversarial: find the risk the doc missed, challenge the vaguest success metric, and pressure-test the "not AI" recommendation — would it survive a sponsor whose budget depends on the AI project? Finish with the one change that would most improve this scoping doc. My discovery pack follows below.
- Ask "why" before your next ticket — and this time write the answer down as one asked-vs-needed sentence: what the ticket asks for, and what problem it's actually serving.
- Translate one trade-off. Explain a real technical trade-off from your current work to a non-technical colleague — then ask them to repeat it back. If it comes back wrong, your translation failed, not their listening.
- Draft one "against AI" case. Find one AI proposal (or existing AI use) at your workplace you'd argue against, and write the one-paragraph case: their goal, the evidence, the boring alternative.
Check yourself — think like an FDE
Scenarios, not recall. Diagnose from the mental model — don't scroll up. Wrong picks stay live.
Scenario A
FDE interview, decomposition round. The prompt: "A hospital network wants an AI assistant to reduce nurse workload. How would you approach it?" You know this domain cold — you can already picture the agent architecture, the RAG layer, the eval harness. The interviewer waits. What's your opening move?
Scenario B
Week three of a phased engagement. On a status call, the sponsor says: "This is going great — while you're in there, can the copilot also draft patient billing disputes? Should be small." It isn't small: new data source, new risk owner, and phase one's eval targets aren't hit yet. Everyone on the call is looking at you. What's the FDE move?
Scenario C
Your eval harness shows the note-drafting system's judge-scored accuracy went from 0.81 to 0.94 after a month of iteration, but the CFO — who signs the renewal — asks bluntly: "So does this thing work or not?" You have thirty seconds. What do you say?
Recommended learning
Hand-picked follow-ups. None are required — the primary source above comes first.
- Article A Primer on Talking to Customers From Rob Fitzpatrick's The Mom Test — Sachin Rekhi The best short summary of the discovery-question discipline this lesson borrows: their life not your idea, past not hypothetical, commitment over compliments.
- Article How to Build Your 1st FDE Team — Per Aspera Reread it after this lesson — the day-to-day it describes is discovery, scoping and adoption work, and now you have names for all of it.
- Article 2026 FDE Hiring Trends: What 1,000 Job Posts Reveal — Perspective AI The market evidence that discovery ability is the fastest-growing FDE requirement — useful ammunition for your own interview narrative.
- YouTube Rob Fitzpatrick — How To Talk To Your Customers (The Mom Test) — The Learning Leader Show The author walking through the method in conversation — hear how the questions actually sound before you run the lab's discovery role-play.
- YouTube How To Do A Software Demo — Matt Wolach A sales-side view of demo craft — discovery before demo, one workflow, end on a commitment. Translate "close the deal" to "open the engagement" and it's the FDE playbook.
References
- Exponent, "FDE Interview: The Definitive 2026 Guide" (2026) — the decomposition round; most common rejection: jumping to a solution; "half engineer, half consultant, full owner".
- Matt Gold, LinkedIn post on FDE hiring criteria (2026) — problem discovery and translation among four competencies weighed over coding; translation "the hardest of the four to find"; models are persuasive when wrong.
- Perspective AI, "2026 FDE Hiring Trends: What 1,000 Job Posts Reveal" (2026) — skill shift toward customer-discovery ability; 95% of enterprise GenAI pilots show no measurable impact.
- Palantir, "A Day in the Life of a Palantir Forward Deployed Software Engineer" (2020) — consistently identifying the most valuable thing to work on.
- Per Aspera, "How to Build Your 1st FDE Team" (2025) — engagement day-to-day: on-site integrations, user training, days-to-weeks cycles, high autonomy.
- Gergely Orosz, "What are Forward Deployed Engineers?", The Pragmatic Engineer (2025) — the FDE/SA boundary: FDEs write production code on customer infrastructure.
- Rob Fitzpatrick, The Mom Test (2013) — discovery-question discipline: their life not your idea; specific past incidents over hypotheticals; talk less, listen more.