Option 1 — Manual prompting
Ask each engine your target query and record the answer. Pros: free, no setup. Cons: slow, inconsistent between sessions, easy to forget, hard to compare over time.
Option 2 — Spreadsheet logging
Same as manual, but logged per query / engine / week. Pros: you build a time series you can actually review. Cons: still labor-intensive, and there's no scoring to compare at a glance.
Option 3 — A dedicated visibility tool
GeoVisor audits across ChatGPT, Perplexity, and Google AI Overviews for a target query + URL, returns a 0–100 GEO score, surfaces competitor gaps, and gives a prioritized fix list. Pros: consistent, repeatable, scalable. Cons: a paid tool (a Free tier with limited scans per month is available; Pro is $39/mo).
Option 4 — Doing nothing
You stay blind to the gap until a customer happens to tell you. Usually the most expensive option, because you can't prioritize what you can't see.
How to choose
If you track fewer than ~5 queries, manual + spreadsheet is a reasonable start. Beyond that, a tool's consistency usually pays for itself in time saved and in catching drift you'd otherwise miss.