# Guided Exercise: Write Your Hypothesis Before You Look at the Answer

This is a paper exercise — commit to a full framework pass before touching the Lab.

## Your task

You're told: "A script that's supposed to write a `ready` marker file isn't creating it, and
exits with a non-zero code." Before running anything, write out, specifically:

1. What's your OBSERVE statement (the precise symptom, not "it's broken")?
2. What EVIDENCE would you gather first, and with what command?
3. What's ONE specific, testable hypothesis (not "something's wrong with it")?

## A worked shape to check yourself against

1. Observe: "Script X exits non-zero and does not create file Y."
2. Evidence: redirect both stdout and stderr to a file and read it —
   `script.sh > log 2>&1; cat log` — the script's own error output is almost always the fastest
   evidence source for a startup failure.
3. Hypothesis (once you've actually read the error): something SPECIFIC the error names —
   e.g. "the script requires a file at path X that doesn't currently exist" — not a vague
   restatement of the symptom.

## Instructor Notes

**Facilitation:** The value here is entirely in getting students to write a hypothesis
SPECIFIC and FALSIFIABLE enough that they could be proven wrong — "something's misconfigured"
fails that bar; "the config file at this exact path is missing" passes it.

**Approximate timing:** 8-10 minutes live discussion; 5 minutes self-paced.