---
title: "Citations"
description: "How an answer cites its sources, what a citation contains and how the source field of a resource appears in it."
canonical: "https://lookio.app/docs/guides/citations"
updated: "2026-11-08"
---

# Citations

Every answer comes from passages of your resources, and cites them. In the text, a citation is a number: `[1]`, `[2]`. The numbers follow the order of the answer: the first source it uses is always `[1]`.

![An answer with the sources open: source 1 from the help center article Issue a credit note, with its section path, passage and address, and source 2 from the refund policy](/docs/images/app/chat-sources.webp)

_Open the sources under an answer to read each passage, its path and its address._

## What a citation contains

| Field                     | Meaning                                           |
| ------------------------- | ------------------------------------------------- |
| `n`                       | The number the answer cites it by.                |
| `resource_id` and `title` | The resource the passage comes from.              |
| `text`                    | The passage itself, as indexed.                   |
| `section`                 | The headings above the passage, outermost first.  |
| `page`                    | The page, for PDFs, slides and other paged files. |
| `url`                     | The address, for a web page or a page of a site.  |
| `source`                  | The resource's **Source** field, when it has one. |

In the app:

- Hover over a number to read the passage.
- Click a number to open the source address in a new tab, or the resource when there is no address.
- Open **sources** under the answer to read every passage, with its path (title, headings, page) and its address or source.

## Make citations useful

- **Give long texts real headings.** Section paths come from Markdown headings. With `# Refunds` and `## Digital goods`, a citation gets a path.
- **Fill the Source field.** Set it to the address or reference that a reader must look up, such as "Employee handbook, 2026 edition". It appears with every citation of the resource.
- **Use clear titles.** The title is part of every passage and of every citation.

## How an answer is built

```mermaid title="From a question to a cited answer"
flowchart LR
  Q["Question"] --> S["Search by meaning<br/>and by keywords"]
  S --> B["Best passages<br/>12 (Deep reads more)"]
  B --> M["Model, with the context,<br/>guidelines and last messages"]
  M --> A["Answer"]
  A --> C["Only the passages<br/>the answer cites"]
```

1. Lookio searches the assistant's resources, by meaning and by keywords.
2. It keeps the best passages.
3. It gives them to the model, with the question, the assistant's context and guidelines, and the last messages of the conversation.
4. The model answers only from those passages and cites them.
5. Lookio returns only the passages that the answer cites.

## What to rely on

A citation shows the passage that the answer used, so you can check a claim in seconds. When you pass an answer on, include its citations. When the stakes are high, read the passage.

When the sources do not answer a question, the assistant says so. It does not guess, and the answer has no citation.

## In the API

An answer has `citations` next to `answer`. See [Ask an assistant](/docs/api/assistants/query-assistant) for the fields. A stored conversation returns the citations of every answer. See [Retrieve a conversation](/docs/api/conversations/get-conversation).

> **Note**
>
> Past answers keep the passages they quoted. If you edit or delete a resource later, old conversations still show the passages that the answer used.