Article Ecommerce
AI agent for WhatsApp with a product catalog: when to use exact search and when to use RAG
How to connect an AI agent to products, compatible references and stock without making every answer slow or unreliable.
Practical guide
Built to help you decide, prepare and review a concrete part of your agent before customers use it.
When a business sells many products, an agent cannot rely only on a FAQ page. It needs to check catalog data, references, compatibility, stock and conditions before replying.
The key is not putting everything into a huge document. The key is deciding what needs exact search and what should be handled with semantic knowledge.
Not everything should go into RAG
RAG works well for policies, explanations, repeated questions and content that can be phrased in many ways. A catalog with references, compatible vehicles, sizes, variants or SKUs needs structured search.
If a customer asks for an exact reference, the agent should check exact data. If the customer asks “do you have brake pads compatible with my model?”, it needs to combine compatibility search with a clear answer.
What to separate
| Data type | Better approach | Why |
|---|---|---|
| SKU, reference, EAN | Exact search | There is no room for approximation |
| Product name | Text search with typo tolerance | Customers may write it incorrectly |
| Compatibility | Structured query | It depends on brand, model, year or variant |
| FAQs | RAG | The wording changes a lot |
| Policies and shipping | RAG + rules | Conditions need explanation |
This separation makes the agent faster, cheaper and more reliable.
What the customer receives
The customer should not notice the architecture. They should see a useful answer:
- Product found or a close alternative.
- Compatibility explained carefully.
- Price or range if available.
- Stock state if the business publishes it.
- Next step: buy, reserve, leave contact details or talk to the team.
If there is no certainty, the agent should say so. In parts, health, technical products or regulated categories, invented compatibility can be expensive.
Sync: simple and frequent is usually enough
For many businesses, syncing every few hours is enough. If stock changes very quickly, the agent can query live data. The important part is deciding which data needs real time access and which data can live in a prepared copy for the agent.
A good first version is usually:
- Sync products and compatibility data.
- Create exact search for references.
- Add typo-tolerant search for product names.
- Use RAG for questions, policies and commercial explanations.
- Store conversations to find catalog gaps.
That gives the agent a stronger first version and makes it improve with real usage.
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