CLN Operator · Reference
?
Question
Unknown · Hypothesis · Open Issue
"What don't we know?"
Operator CLN v2.1 Plain-text · Universal
All operators =Equals .Dot !Bang ?Question →Arrow ~Tilde +Plus -Minus @At
01// ? — Definition

Marks unknowns. Surfaces hypotheses. Tracks open questions.

Cognitive question answered: "What don't we know?"
One line = one semantic unit. The Question operator tells the reader — before they read the content — that this line answers: What don't we know?
02// When to use it

Use ? for anything unverified, uncertain, or requiring investigation. Open questions, hypotheses that haven't been tested, gaps in current understanding.

When NOT to use it:
Don't use ? for rhetorical questions in explanations — use prose for those. ? marks a genuine epistemic gap that needs resolution.
03// Live Examples
Debugging session
?recent deploy? — check git log vs spike onset time
?upstream dependency down? — payment gateway / session svc
?DB pool exhausted? — check connection wait times
?traffic spike beyond capacity? — compare req/s to ceiling
Research gaps
?long-term culture impact — unknown — 47 studies, none > 3yr
?individual tolerance variability — not fully modelled
?short sleeper phenotype — rare variant — ADRB1 / DEC2
Product planning
?does our ICP actually use CLI? — assumption — not validated
?what triggers upgrade to team plan? — no data yet
?competitor roadmap after Series B? — unknown
04// Operator Pairs

Operators don't work in isolation — they form semantic pairs that together convey full cognitive structure:

!! = known risk · ? = suspected but unconfirmed risk
.? marks what to investigate · . is the investigation step itself
→? is the open question · → is the answer when found