Build the index

The index lets the assistant find the right paragraph by meaning, even when the visitor uses different words from your document. You build it by clicking Build the index at the top of Answer Desk > Knowledge.

What is the index?

Each document is split into chunks (short pieces of text). The index provider turns each chunk into a list of numbers that describes its meaning (these are called embeddings or vectors). When a visitor asks something, the question is turned into numbers the same way and compared with your chunks. Everything is stored in your own WordPress database: no extra service is needed.

Build it

1. Go to Answer Desk > Knowledge.
2. The box at the top shows the count of chunks indexed and how many are still to index, with an estimated cost in dollars.
3. Click Build the index. It runs in batches with a progress bar; you can watch it without the page freezing.
4. When it finishes, the box says The index is complete. Every document is searchable by meaning.

The cost is usually a few cents for a whole site. The estimate is an order of magnitude; the real bill comes from your provider.

When to build it again

• After you upload or import new documents.
• After you edit an imported page: its text is refreshed automatically, but its new chunks need indexing.
• After you change the index provider or index model (see below).

You do not have to remember this. When documents or imported pages change after the index was built, Answer Desk marks the index as out of date: a notice appears at the top of the admin screens (Answer Desk: the index is out of date.) with a Build the index link, and on Start here the Build the index step loses its tick. Both go away when the index is complete again. The plugin does not rebuild the index by itself, because each build is a paid request to your provider.

Who builds the index

On Answer Desk > AI provider, the Who builds the index card has two settings:

• Index provider: by default The same one that answers, when it can. ChatGPT, Gemini and Mistral can. Claude and OpenRouter cannot, so choose Voyage AI, ChatGPT, Gemini or Mistral here (with its key saved in the Keys card).
• Index model: the recommended model is listed first. Leave it unless you know why you want another.

Without an index

If no index provider is set, the assistant still works by matching words instead of meaning, and the Knowledge screen says so. It will miss questions asked in different words, so building the index is strongly recommended.

Very large archives

The search runs inside WordPress. On a very large index (many thousands of chunks), the server may not be able to search all of it in time. When this happens the plugin says so in the Try it results instead of slowing down silently. Remove documents the assistant does not need, or split very long ones.