Zapier / Make wins when the rules are stable
If the task can be specified as "when X happens, do Y, then Z" with no ambiguity, rules-based wins. It's cheaper, faster, more reliable, and easier to debug.
- Move data between SaaS tools (Stripe → QuickBooks, Calendly → CRM, form → Slack).
- Scheduled tasks (daily report email, weekly CSV pull, monthly invoice generation).
- Notifications based on field changes ("alert when deal stage = Closed-Won").
- Data validation with fixed rules (required fields, format checks, dedup).
AI wins when judgment is required
If the input varies in ways that can't be fully specified up front — natural language, ambiguous categorization, contextual personalization — an LLM in the loop pays for itself.
- Reading and classifying inbound email/SMS (spam, sales, support, partnership).
- Drafting personalized replies that reference customer history.
- Extracting structured data from unstructured documents (invoices, BOLs, receipts).
- Summarizing meeting notes, call transcripts, support tickets.
- Generating content (marketing copy, product descriptions, social posts).
Most production systems combine both
The real-world answer is rarely either/or. A typical reactivation engine looks like:
- Rules-based pull from CRM — "dormant customers, last service > 12 months" — deterministic.
- LLM-based generation of personalized SMS body — reads the customer's service history, drafts a hyper-relevant message.
- Rules-based send via Twilio API — deterministic.
- LLM-based reply handling — reads inbound responses, classifies intent, drafts replies.
- Rules-based handoff to dispatch system — deterministic.
Why hybrid
LLM calls are 10-100x more expensive than rules-based steps. Using an LLM where rules suffice burns money. Using rules where judgment is needed produces bad outputs. The hybrid approach uses the right tool at each step.
What you're actually paying for
Rough cost model:
- Zapier — $30-$800/month depending on task volume. Pay per task, no per-step variable cost.
- Make — typically half of Zapier at equivalent volume. More flexibility, steeper learning curve.
- OpenAI / Anthropic API — $0.001-$0.05 per LLM call depending on model and prompt length. Variable.
- Custom orchestration (Workers, Lambda, Cloud Run) — $5-$50/month for small business volume. Most flexible, most engineer-time to build.
When to skip the SaaS layer entirely
Zapier and Make are great for prototyping but expensive at scale. Once your task volume crosses ~5,000 automations per month, custom-built orchestration on Cloudflare Workers or AWS Lambda becomes cheaper and more reliable. The HG Oil Holdings invoicing assistant is built this way — direct API integration, no Zapier middleware. Lower ongoing cost, faster execution, more control over error handling.
