Use <see> for an inline link and <seealso> for an entry in the generated related-links section. Choose the target attribute by what you are linking to:

Attribute	Target
cref	Symbol that Delphi source analysis can resolve
href	External page
xref	Topic exported by the DocInsight documentation system

Use cref for a symbol in the analyzed Delphi compilation environment:

/// <summary>
///   Creates a new <see cref="IList{T}" /> instance.
/// </summary>
class function CreateList<T>: IList<T>; static;

DocInsight resolves cref by Delphi symbol identity rather than by a generated output path. When the referenced symbol has a published API topic, the generated link points to that topic.

Use href for an external URL:

/// <seealso href="https://docinsight.github.io/mylibrary/">
///   MyLibrary documentation
/// </seealso>

Use xref for an explicit DocInsight cross-reference. The value contains the target Xref namespace and source-owned topic identity. Delphi API topics use the effective namespace assigned to their Delphi project by the source's xref settings:

/// <seealso xref="mylibrary/MyLibrary.Collections/TCollections">
///   TCollections
/// </seealso>

When project.name is mylibrary and the source has no namespace override, mylibrary is the default namespace. The Delphi content name, such as api, does not become part of the Xref. Package local IDs start at the unit. Program and library local IDs also include the Delphi project name; use an exact project namespace override when that would produce a redundant Xref such as mylibrary/mylibrary.tests/.... The override shortens it to mylibrary.tests/....

Markdown topics continue to use their content entry name as the namespace, so an API comment can link to a guide in the same documentation project like this:

/// <summary>
///   See the <see xref="docs/collections">collections guide</see> for usage patterns.
/// </summary>
/// <seealso xref="docs/collections">
///   Collections guide
/// </seealso>

For the Delphi source namespace configuration and project override precedence, see Configure Xref namespaces. For Markdown topic identities, see Add links and cross-references.

Use <img> with a relative src path to include an image in XML documentation. DocInsight resolves the path from the .pas file containing the comment:

/// <remarks>
///   The following diagram shows the collection hierarchy.
///   <img src="./images/collection-hierarchy.png" alt="MyLibrary collection hierarchy" />
/// </remarks>

The src value must be a relative filesystem path. Paths beginning with /, operating-system absolute paths, and URLs are not supported. The resolved image must remain inside the configured Delphi source root; paths and symbolic links that escape it are rejected. For ownership and publishing rules, see Content-local assets.

Use <paramref> and <typeparamref> for parameter and type-parameter names in inline text:

/// <summary>
///   Gets the value at the specified <paramref name="Index" />.
/// </summary>
function GetItem(Index: Integer): T;