How to Prepare When You Don't Have a Job Description

In this chapter

Chapter one assumes a posting.

Plenty of real processes do not: a referral, an internal move, a recruiter who says “we’ll write the JD after we meet you,” a founder screen, a “come talk to the team.” The calendar invite is real. The document is not. Preparing a generic title is how you walk into someone else’s interview.
There is still a hiring spec.

Someone has a problem they want a person to absorb. Your job is to reconstruct that spec well enough to practice — and to ask for the real document without sounding like you are stalling.
This chapter is the inverse of reading a posting.

Same output: eight to twelve atoms. Different inputs. If a posting arrives later, throw the proxy out and start chapter one again. Do not marry the guess.

Before you invent a role, ask.

One sentence to the recruiter or the person who opened the door: “Is there a job description or a short brief I can prepare from?” Many teams have an internal spec they did not post. Asking is competent. It is not needy.
If they send a paragraph, treat it as a posting.

Annotate it. If they send nothing, you have information: the process is informal, and the interview will be driven by whoever is in the room that day. Informal is not easier. It is less predictable. Your proxy spec has to be wider, and your first two minutes have to pull the real spec out of them.
Do not wait a week for a document that will not come.

Ask once, then build the proxy the same day.

Use five sources, in this order.

One: whatever they already said — email, LinkedIn message, the referring person’s one-liner (“they need someone who can calm down the Friday close”). Write those words down. They will reappear in the room.
Two: the team’s public work.

Product pages, papers, store locations, clinic hours, a 10-K risk factor, a GitHub org, a teacher’s public curriculum. You are looking for the work, not the brand story.
Three: similar postings from the same company or a close competitor for the same level.

Steal verbs, not a fantasy stack. If three nearby postings all say “own the forecast” and none say “build a brand-new data platform,” believe the forecast.
Four: the conversation you are about to have.

A founder screen is often “can you help me think.” A hiring-manager coffee is often “can you do this week’s fire.” A panel with no JD is often each person interviewing for their own pain. Mark which it probably is.
5
Five: your own last comparable job, used as a hypothesis you will test, not as a speech.
- “In my last role I owned X
- I want to check whether that is the hole here.” That sentence is prep. Reciting the last role as if it were this one is not.

Without a posting, the first useful move in the room is to confirm the job.

Thirty seconds: “I prepared as if this role is mainly A, with B as the constraint, for C as the customer or stakeholder. Is that the job, or should I throw that out?” Good interviewers will correct you. That correction is the job description. Write it down. Pivot.
If they cannot describe the job, you are in a fishing process.

Stay specific anyway. Offer two or three ways you have done adjacent work and ask which pain is loudest. You are helping them hire, not performing mystique.
Do not spend the hour proving a role they do not have.

A brilliant answer to the wrong problem is a no.

Do not paste “software engineer” into a question generator and call it prep.

Title-only kits are the generic bank with extra steps.
Do not overfit to the referring friend’s gossip.

Referrals are a door, not a spec. Friends flatten the work into a compliment.
Do not refuse to interview until a perfect JD appears.

Some companies never write one. You can still decide later, with more data, whether the work is real.
Do not pretend you read a posting you never saw.

If they ask “which part of the JD stood out,” say you were not sent one, and name the proxy you used. Honesty here is cheaper than a bluff.

You are done when you have a one-page proxy: eight to twelve atoms, labeled as guesses, plus one opening question that will confirm or kill the guess in the first minutes.

You also sent one ask for a real brief.
If a posting shows up tonight, switch to chapter one.

The proxy was scaffolding. The next chapter is the opener almost every process still uses — with a JD or without — “tell me about yourself,” which is a narrative, not a résumé.

Generate questions from that job description — free preview, $2 for the full kit. No account. Paste a job description.