Sidecar files

Sidecar files are standalone JSON metadata files stored alongside your book files on disk. They provide a portable, human-readable backup of book metadata that can be imported into Trove or used with other tools.

File Format

For a book named MyBook.epub, the sidecar files are:

MyBook.metadata.json containing all metadata
MyBook.cover.jpg (optional) containing the cover image

The JSON file follows this structure:

{
  "version": "1.0",
  "generatedAt": "2026-01-15T10:30:00Z",
  "generatedBy": "trove",
  "metadata": {
    "title": "My Book",
    "authors": ["Author Name"],
    "publisher": "Publisher",
    "publishedDate": "2025-03-15",
    "description": "...",
    "isbn13": "9781234567890",
    "categories": ["Fiction", "Thriller"],
    "language": "en",
    "pageCount": 350
  }
}

Included Fields

Title, subtitle, authors, publisher, published date, description
ISBN-10, ISBN-13, page count, language
Categories, moods, tags
Series name, number, and total count
External identifiers (ASIN, Goodreads ID, Google ID, Hardcover ID, ComicVine ID, and others)
Ratings from each metadata provider (average and count)
Age rating, content rating
Audiobook-specific fields (narrator, abridged)
Comic metadata (for comic books)

Only non-null fields are included in the output.

Settings

Turn sidecars on in Settings › Metadata 1, under Sidecar JSON Files (see Metadata settings):

Setting	What it does
Enable Sidecar JSON	Allows sidecar files at all
Write on Metadata Update	Updates a book's sidecar whenever its details are edited
Write on Initial Scan	Creates sidecars when books are first added to a library
Include Cover Image File	Also saves the cover as `BookName.cover.jpg`

To read metadata back from sidecars during scans, set a library's Metadata source to Sidecar Only, Prefer Sidecar or Prefer Embedded (see Your first library). Sidecars aren't written when DISK_TYPE=NETWORK is set; on a network share with the default setting they're written with the same verified copies as books.

Per-Book Operations

On a book's page, the Sidecar tab shows:

A sync status badge indicating whether the sidecar is in sync, outdated, conflicting, missing, or not applicable
The current sidecar JSON content
Export button to write the sidecar file to disk
Import button to update Trove metadata from an existing sidecar file

Library-Wide Operations

In Settings › Metadata 2 (Library metadata), each library has:

Export Sidecar generates sidecar files for every book in the library
Import Sidecar reads sidecar files from disk and updates Trove metadata for all books that have them