# When a customer asks for a new use case, the FDE answers first

> The skill is not selling but replying without committing, then routing the signal to whoever owns expansion, which differs from company to company.

Original: https://fdetimes.net/en/guides/fde-customer-asks-new-use-case/

Picture yourself in the third week of a deployment. The invoice-extraction pipeline is finally running reliably on real data. The customer's head of operations watches the demo, nods, and asks: "Can this read customs declarations?"

That question could lead to a bigger contract. It could also turn into a promise nobody at your company agreed to. The Account Executive (AE) and Customer Success Manager (CSM) are not in this demo, so the FDE has to answer first.

The skill needed here is not selling. You need to recognise the signal, answer without committing, and send the signal down the right path. Get it wrong and the AE loses the opportunity, or the CSM feels their work has been taken, and the customer hears three people say three different things.

## Who actually owns the expansion signal?

The honest answer is that it depends on the company. Firecrawl's FDE job posting states outright that account expansion is the FDE's responsibility: finding opportunities to grow usage, add use cases and expand the contract. The posting also says the FDE does not wait for a CSM to flag an upsell opportunity, because there the FDE is treated as the person closest to the customer.

Chad Horenfeldt, a customer success leader, describes the opposite model: most of the work of renewal and finding expansion opportunities belongs to the CSM.

His view is that the deeper people go into building and designing solutions, the further they move from revenue. He also offers a hypothesis about the friction: perhaps sales sees customer success encroaching on its territory.

Underdog.io defines the FDE as a post-sales technical role that does not close deals and carries no quota. The FDE is measured on three things: whether the customer actually uses the product, whether the product solves the business problem, and whether the customer renews.

The last two measures almost overlap with the work of customer success. So three roles touch the same signal, but each is measured on something different.

**Key point:** The FDE spots the expansion signal; the person who carries the quota quotes the price.

## In the meeting, what do you tell the customer?

Back to the customs declarations question. A good answer has three parts: acknowledge the question, ask more about the problem, and say clearly who will come back to discuss scope. A sample script:

"That's a really useful question. Can I ask a bit more: roughly how many declarations do you handle a month, who processes them today, and where do errors usually creep in? We'll send you a note on technical feasibility this week. On scope and the contract, Lan from our account team will be in touch."

The script deliberately avoids three lines that slip out all too easily: "Sure, that's easy", "It probably won't cost any extra" and "Let me try it over the weekend". The first is a technical commitment made before seeing any data.

The second is a pricing commitment, which is not the FDE's to make. The third turns a commercial opportunity into free work outside the scope.

## Writing a signal note: five lines are enough

The same day, write a short note and post it in the account's shared channel, not in a private message to one person. For the customs declarations example, a five-line template might look like this:

```
Who said it: head of operations, during the demo on date X
Problem: customs declarations are processed manually; customer estimated the volume themselves
Current evidence: invoice pipeline runs on real data, operations team uses it daily
Technical feasibility: need sample declarations to assess, nothing promised yet
Told the customer: AE will be in touch about scope
```

The "told the customer" line matters most. It tells the AE and CSM what the customer is waiting for, so nobody accidentally contradicts you on the next call.

## Route it to the AE or the CSM?

When the company has no clear rule, you can classify by the nature of the signal, as the chart at the top of the article suggests. If the customer is using more within the same use case, or shows signs of not renewing, the CSM leads.

If there is a new department or buyer, the AE leads. A new use case with the same buyer means the two discuss it together. This is a sensible split, not a law, so confirm it with the account's AE and CSM.

The new-buyer case matches Firecrawl's description: the FDE works alongside the growth team to show the technical buyer how the product solves their problem. The FDE is present in the commercial conversation, but as the person bringing evidence, not the one settling the price.

## Mistakes that cost the FDE goodwill on both sides

The first mistake is sitting on the signal. Imagine an FDE sees the customer needs more, builds a trial version on the side for fun, and the AE finds out three weeks later. By then the customer is used to getting work for free, and the contract conversation becomes awkward.

The second mistake is the opposite: turning yourself into a salesperson. Perspective AI's playbook warns that when FDEs report to the CRO, compensation, OKRs and the politics of the go-to-market organisation push them to chase billable hours with customers instead of building reusable parts of the product.

Every new request becomes a one-off project, and the product learns nothing.

The third mistake is forgetting that you will leave. The same playbook advises that most FDE engagements should hand over to customer success and product engineering within 120 days of go-live. Any signal you do not record leaves with you when you leave the account, and the CSM who takes over has to start from scratch.

## Read the job description to know which model you are walking into

KORE1 notes that some companies place FDEs under the CRO's organisation, so reporting lines vary from place to place. It also observes that postings mixing the titles sales engineer, solutions engineer and FDE are almost always FDE roles whose scope was written by someone in sales.

So in interviews, ask three questions: who you report to, who owns the expansion number, and which channel signals from FDEs go through. If the job description includes a phrase like "drive account expansion", as Firecrawl's does, have a concrete story ready about a time you spotted a new customer need and passed it to the commercial side.

On your CV, do not write "supported sales". Write it as a sequence: which use case you spotted, what evidence you had, who you passed it to, and what came of it. People hiring FDEs want to see that you understand the boundary, not just that you are keen.

Next time a customer asks "can this do X?", you will have a few seconds to answer. Use them to ask more about the problem, not to make a promise.

**Try this week:**

- Go back through your notes from customer sessions over the past two weeks, find at least one question along the lines of 'can this do X?' and write it up as a signal note
- Ask the AE and CSM on your current account what kind of signals each of them wants to receive, and through which channel
- Add a line to your CV describing a time you spotted a new use case and passed it to the commercial side with evidence

## Sources

- [Forward Deployed Engineer, Firecrawl](https://scoutify.com/companies/firecrawl/jobs/735876/)

- [Forward deployed engineers as CSMs: It's a trap](https://chadhorenfeldt.substack.com/p/forward-deployed-engineers-as-csms)

- [What Is a Forward Deployed Engineer in 2026](https://underdog.io/blog/forward-deployed-engineer)

- [What Is a Forward Deployed Engineer? Role, Skills & Salary](https://www.kore1.com/forward-deployed-engineer/)

- [How to Build a Forward-Deployed Engineering Function: A 2026 Founder's Playbook](https://getperspective.ai/blog/how-to-build-forward-deployed-engineering-function-founder-playbook-2026)