Channels — Meta, Google, TikTok, Microsoft, and why they're not interchangeable
Each ad channel has its own audience, format, pricing, and policy regime. The same ad does NOT belong on every channel. Knowing this saves you from a class of expensive mistakes.
The plain-English version
When someone says "we should advertise online," they usually mean a specific thing without realizing it. The two main "online ad worlds" are:
- Search: someone types a query into Google (or Bing). You bid to appear next to specific keywords. The user is actively looking for something. Intent is high.
- Social: someone is scrolling through Facebook, Instagram, TikTok, etc. You bid to interrupt the scroll. The user is not looking for you. Intent is low; you create interest from scratch.
These two require completely different ad copy, completely different visual styles, and have completely different policy regimes for our vertical.
The four channels in scope for V1
The pipeline ships variants to two channels in V1, with two more on the horizon. Each has its own format rules and policy floor.
Meta (Facebook + Instagram)
Format: image, carousel, reel, story. Caption-heavy. Audience: broad — Maya, Jess, some David, some Rachel. Strengths: scale, sophisticated targeting, visual storytelling. Weaknesses: rising CAC, tightening policy, weight-loss vertical under state-AG pressure (Dec 2025 35-AG letter).
Policy floor: LegitScript certification + Meta internal review required for prescription GLP-1. No before/after imagery. No "free trial" or "no commitment" framing. Full detail in platform policies.
Character limits: hook ≤ 40, body ≤ 125, CTA ≤ 20. These come up in copy review constantly. Internalize them.
Google Search Ads (GSA)
Format: Responsive Search Ads (RSAs) — multiple short headlines and descriptions that Google mixes. No images, no video. Just text. Audience: intent-driven — David and Rachel especially. Strengths: high intent, predictable cost per qualified click, durable across vertical regulation shifts. Weaknesses: can't target competitor brand terms; capped by keyword volume.
Policy floor: LegitScript Healthcare Merchant Certification + ad- account-level pre-approval. Cannot bid on competitor brand terms (Wegovy, Ozempic, etc.).
Character limits: headlines ≤ 30, descriptions ≤ 90. These are extremely tight. The copy_polish node enforces them.
TikTok
Format: short vertical video. Algorithm-driven, not targeted. Audience: younger than our ICP; not where Maya/David/Rachel live. Strengths: virality potential, low CPM where allowed. Weaknesses: prescription weight-loss is BANNED outright — no certification will unlock it. Organic content remains an option but isn't a paid channel for our category.
For Eudaven, TikTok is not a paid channel for GLP-1. We mention it in lessons so you know why it's not in the V1 brief matrix.
Microsoft Advertising (Bing)
Format: similar to Google Search Ads. Audience: skews older and more affluent than Google — interesting fit for David and Rachel. Strengths: lower CPC than Google for the same intent. Weaknesses: smaller volume; some Microsoft Audience Network inventory restricted for the vertical even with certification.
V2 expansion target. Not in the brief matrix yet.
What "channel-appropriate copy" actually means
The biggest non-obvious lesson here: copy that works on Meta does not work on Google Search. Here's why:
- Meta copy can be longer-form, can establish context, can build emotional resonance. Visual carries some of the weight. The reader is in scroll mode — copy has to earn the stop.
- Google Search copy is short, dense, specific. The user has already declared intent ("compounded semaglutide telehealth") in the query. Your job is to confirm you have what they typed and to qualify them for the right next step.
The same headline can't do both jobs. That's why the brief always
declares channel_name and why downstream nodes (copy_polish
especially) produce different schemas per channel.
How channel interacts with persona
Channel choice should match where the persona actually is:
| Persona | Best primary channel | Secondary |
|---|---|---|
| Maya | Meta (IG feed + reels) | Google Search |
| David | Google Search | Meta (clinical-toned only) |
| Jess | Meta | Google Search |
| Rachel | Google Search | Meta (consideration only) |
If a brief pairs Rachel with TikTok, something is wrong. (And TikTok would reject it anyway.)
How to recognize the wrong channel
Quick checks:
- Copy mentions Wegovy / Ozempic by brand on Google Search? That will get rejected — competitor brand bidding restriction.
- Long-form clinical copy on TikTok? Wrong channel for both format and policy reasons.
- Single-headline-only copy targeting Google Search? Google needs multiple headlines to compose RSAs. Single headlines underperform.
- Static carousel destined for Instagram Reels? Format mismatch.
Going deeper — official training from each platform
When you want more depth than this lesson, go directly to the platforms' own free training. Each one is the canonical source for how that platform thinks about its own product.
- 🎓 Meta Blueprint — free self-paced courses. Start with "Get started with ads."
- 🎓 Google Skillshop — free Google Ads training. The Search Certification track maps directly to our GSA work.
- 🎓 TikTok Academy — useful for understanding the platform, even though prescription weight-loss advertising is banned for us.
- 🎓 Microsoft Advertising Learning Lab — similar structure to Google Skillshop.
For the full directory of training and policy resources, see Resources.
What to do next
- Read the channel policy summaries in
data/kb/regulatory/platforms/to see the full posture on each platform. - Pick a recent variant and check: did the brief match this channel's format, audience, and policy floor?
- Read Compliance basics next.