AI agents for customer support · Part 5 of 14

RAG for support teams, in plain words

What happens between a customer’s question and the agent’s answer, where the lookup goes wrong, and why a limit written in an article is not a check.

The short version

RAG is how an AI support agent answers from your knowledge. It searches for the few pieces that best match the question, adds them to the conversation, and writes its reply from them. That works well for answers. It doesn’t work for rules: a limit written in an article holds only when the search finds it.

RAG in three words

RAG stands for retrieval-augmented generation: the agent looks things up, then writes. Ada, for example, documents that its agent keeps the three most relevant pieces and writes its reply from them. When nothing matches, it asks the customer to rephrase or hands over.

Customer asks1 Retrieve3 Generate 2 Augment a questionsearch for the best matcheswrite the reply from them add them to the conversation your knowledge, in pieces the few pieces it keeps If nothing matches asks again, or hands over

A customer asks

↓

1 Retrieve

The agent searches your knowledge, split into pieces, for the best matches.

↓

2 Augment

It adds the few pieces it keeps to the conversation.

↓

3 Generate

It writes the reply from those pieces. If nothing matches, it asks again or hands over.

The model never reads your whole knowledge base. It writes from the few pieces the search hands it, so the answer is only as good as those pieces.

Where the lookup goes wrong

When knowledge that is right gives a wrong answer, look first at which pieces the search found. Three things go wrong there.

1 Different words2 Another customer’s answer3 Yesterday’s copy “Can I send it back?”“How long can I return it?”“What’s the delivery fee?” Returns policyReturns in the EU: 30 daysWebsite: delivery €4.95 never matchedfound for a customer in the USas of the last sync searchessearchessearches The fixThe fixThe fix Title articles with the wordscustomers use (part 4). Give the agent the customer’scountry from your systems (part 6). Know when each outsidesource updates.

1 Different words

“Can I send it back?” never matches the article titled Returns policy.

The fix: title articles with the words customers use (part 4).

2 Another customer’s answer

A customer in the US asks how long they can return an item, and the search finds Returns in the EU: 30 days.

The fix: give the agent the customer’s country from your systems (part 6).

3 Yesterday’s copy

The agent reads your website as of its last sync, before this morning’s new delivery fee.

The fix: know when each outside source updates.

Three ways the search hands the agent the wrong piece, as examples. Each fix is in what you write, or in what the agent knows about the customer.

Zendesk, for one, reads an outside source as it was at the last sync, which usually happens every 24 hours. If your tool shows the source of each answer, check it on 20 real questions before launch; part 10 covers testing in full.

Why a rule in an article is not a check

Say your returns article says “refunds up to €30 need no approval”. To the agent, that is one more piece to find and weigh, not a limit. It holds only when the search finds it, and it can’t count what this customer has already received.

“Refunds up to €30 need no approval” In an article As a rule When it appliesHow it is readWhat it countsWho changes it only when the searchfinds that piece as words the model weighsagainst the conversation nothing: it can’t see whatthis customer already got anyone who can editthe help center on every refund,before the tool acts a yes, a no, or a person’sapproval first this customer’s earlier refunds,across every agent a named owner, whoconfirms each change

“Refunds up to €30 need no approval”

In an article

Applies
only when the search finds that piece
Read as
words the model weighs against the conversation
Counts
nothing: it can’t see what this customer already got
Changed by
anyone who can edit the help center

As a rule

Applies
on every refund, before the tool acts
Read as
a yes, a no, or a person’s approval first
Counts
this customer’s earlier refunds, across every agent
Changed by
a named owner, who confirms each change
The same limit, written in an article and set as a rule. In the article it is one more piece to find and weigh. As a rule, it is checked every time.

Intercom says the same about instructions to its own agent: “You can write phrasing like “Don’t use [article],” but Fin may still use it if it’s the best match.” Its answer is a setting: take the article out of the sources Fin may use.

Intercom, “Provide Fin AI Agent with specific guidance”

So keep in the article what the customer needs to know, such as how long a refund takes, and keep the limit as a rule your tools check before they act. Part 8 shows how to write one, and part 3 why the count has to cover every agent.

Next in this series

Part 6: connecting your helpdesk, store and billing. See all 14 parts.

Where Himmel fits

Himmel is the right-hand column: your team confirms each limit in plain words, and before every refund the agent’s tool checks it with Himmel, counted per customer across every agent.

Sources

  1. Ada, “Content generation”, read on 19 October 2026.
  2. Zendesk help, “Connecting knowledge sources to power generative replies in AI agents”, read on 19 October 2026.
  3. Intercom, “Provide Fin AI Agent with specific guidance”, read on 19 October 2026.