Citations you can actually check

A list of links at the bottom of an answer is not a citation. It is a bibliography, and nobody reads bibliographies. If a model claims that Node 22 stops receiving security fixes in April 2027, the source for that exact claim should sit next to that exact sentence, and one hover should tell you where it came from.

This post is about how AgentJam does that, and about the small decisions that make citations useful rather than decorative.

Where citations come from

When Web Search or Deep Research is on, the model’s output carries annotations: a URL, a title, and the character range in the answer that the source supports.

{
  "type": "url",
  "title": "Node.js Previous Releases",
  "url": "https://nodejs.org/en/about/previous-releases",
  "start_index": 118,
  "end_index": 119
}

The indices are what make inline placement possible. The client walks the answer line by line, keeps a running character count, and drops a marker at the end of the line that contains the annotation’s range. If two sources support the same sentence, both markers appear together.

Numbering that stays stable

Each distinct URL gets one number for the whole answer, assigned in order of first appearance. If the same source is used in the first paragraph and the last, it is number 1 in both places. Readers build a small mental map of the sources as they go, and stable numbers keep that map intact.

This sounds obvious. It is also the thing most chat products get wrong, because they number occurrences instead of sources.

One hover to verify

A citation marker is a small numbered button. Hovering or clicking it opens a popover with the page title and the full URL, both readable in place. If the title and the claim do not match, you have learned something important without leaving the page. If they do match, the URL is one click away.

Two details keep this honest:

• Markers stay in the sentence. They are never floated to the margin or collected at the end. The claim and its evidence share a line.
• The URL is shown in full. Shortened or masked links hide the one thing a skeptical reader needs, which is the domain.

Streaming and citations together

Annotations arrive with the output stream, not after it. As the answer is written, the running character count is compared against each annotation’s end index, and a marker appears the moment the sentence it supports completes. You never see a finished answer suddenly sprout numbers a second later.

What a citation is not

A citation says “this sentence relies on this page.” It does not say the page is right. A model can cite a wrong source accurately. What inline citations give you is the ability to check quickly, and the habit of checking is what makes an assistant trustworthy over time.

Try it

Turn on Web Search from the tool picker and ask something with a concrete, checkable answer. Watch where the numbers land, hover one, and read the title before you read the answer again.