Sources checked
Orbital Notes, standard property, range 2026-09-01 to 2026-09-30. Sources kept exactly as pasted. "Named assistant" means one of the five you listed (ChatGPT, Perplexity, Gemini, Copilot, Claude) matched to its source as it appears in your list.
| Source | Session source | Sessions | Named assistant | Matches my regex | Matches Google example regex |
|---|---|---|---|---|---|
| S1 | 18,400 | no | no | no | |
| S2 | chatgpt.com | 640 | yes | yes | yes |
| S3 | perplexity.ai | 210 | yes | yes | yes |
| S4 | gemini.google.com | 95 | yes | yes | yes |
| S5 | copilot.microsoft.com | 40 | yes | yes | yes |
| S6 | claude.ai | 30 | yes | yes | yes |
| S7 | github.com | 520 | no | no | no |
| S8 | mail.google.com | 160 | no | no | yes |
| S9 | news.ycombinator.com | 300 | no | no | no |
| S10 | openai.com | 12 | no | no | yes |
| S11 | (direct) | 4,100 | no | no | no |
Regex and test
Proposed condition for a channel named AI Assistants: session source matches regex
^(chatgpt\.com|perplexity\.ai|gemini\.google\.com|copilot\.microsoft\.com|claude\.ai)$
Tested by script against all 11 pasted sources (Python re.search; GA4's own regex engine may differ, so recheck in the channel editor preview if it shows one).
| Check | My regex | Google help page example regex |
|---|---|---|
| False positives (match, not a named assistant) | 0 | 2 |
| Named assistants missed | 0 | 0 |
Google example false positives: mail.google.com, openai.com. The example starts with '^.*ai', which matches any source containing the letters 'ai', for example mail.google.com. That is why I wrote an exact list instead. openai.com (S10) is not matched by mine because it is not one of the five you named (question 2).
Sessions that would move
Rule: sessions moving = sum of sessions for sources my regex matches; share = that sum / all pasted sessions.
| Item | Sessions | Share of all pasted sessions |
|---|---|---|
| Matched by my regex | 1,015 | 4.14% |
| Matched by Google example regex | 1,187 | 4.84% |
| All pasted sessions | 24,507 | 100.00% |
This only counts sources that pass a referrer. It cannot show AI assistant visits that arrive without one.
Channel order
Google's custom channel group help says to reorder so the new channel "appears above “Referrals”", because traffic goes to the first channel it matches. Whether to place AI Assistants above Organic Search too is your call: Google's default channel group puts clicks from "Google’s AI Overviews and AI Mode" in Organic Search, and none of the five sources in your list is 'google', so my regex would not take any Organic Search traffic either way.
Setup steps (held)
- Admin, under Data display, click Channel groups.
- Click Create new channel group (it starts as a copy of the default group). You have 1 custom group; standard properties allow 2 in addition to the predefined group, so this fits.
- Add channel 'AI Assistants' with the condition above.
- Click Reorder, drag AI Assistants above Referral, Apply.
- Save group. HELD until you approve.
- Making it the primary channel group: not proposed; you did not ask for it. Custom channel groups can be applied to reports retroactively, per Google's help page.
Questions for you
- Do you want AI Assistants above Organic Search as well, or only above Referral?
- Should openai.com (12 sessions) count as an AI assistant source?
Needs your decision
- Approve saving the channel group (HELD).