One of my favorite Kindle features is X-Ray, which lets you quickly look up characters, places, organizations, and important terms while reading without worrying about spoilers.

Hardcover already has a Characters page for books, which feels like a great foundation for something similar.

Feature Idea:

Expand the existing character system into a community-maintained Book X-Ray.

For each entry (character, location, organization, event, etc.), contributors could add:

Short spoiler-free description
Alternative names or aliases
Relationships with other characters
First appearance (chapter or percentage, when available)
Optional spoiler-tagged information
Links to other related entries

This would make Hardcover a valuable companion while reading, not just after finishing a book.

It would be great if Hardcover exposed an API endpoint for its community-maintained character data.

There is already a Hardcover sync plugin for KOReader, and an endpoint like /books/{id}/characters (or a more general /books/{id}/xray) would allow plugins to provide a Kindle-style X-Ray experience directly inside the reading interface.

Since the data would be maintained by the Hardcover community, improvements would automatically benefit every app and plugin that integrates with it.