CalibreDB

Use this skill for all command-line operations on Calibre libraries.

Library path

• Calibre library locations are user-specific. Identify the target library path or Content server URL before running commands.
• Prefer explicit path in every command: --with-library "$CALIBRE_LIBRARY".
• If the user has not provided a library path, ask for it or inspect the local environment for an existing Calibre library before proceeding.
• For machine-readable outputs, use --for-machine or JSON-capable subcommands.

Safety model

Start with read-only operations, then escalate only when needed.

Read-only (safe by default)

• list
• search
• show_metadata
• custom_columns
• list_categories
• check_library
• fts_search
• fts_index status

Mutating (confirm intent for destructive/irreversible)

• Usually safe with clear intent: add, set_metadata, set_custom, add_format, embed_metadata, backup_metadata
• Confirm before destructive actions: remove, remove_format, remove_custom_column, restore_database, fts_index reindex on full library

Core workflow

1. Identify target library and set --with-library.
2. Discover relevant book IDs with search (or list --search).
3. Inspect records with show_metadata or list --for-machine.
4. Apply minimal required mutations.
5. Validate with follow-up list/search/show_metadata.

Quick command patterns

1) List books

export CALIBRE_LIBRARY="/path/to/Calibre Library"
calibredb list --with-library "$CALIBRE_LIBRARY" --fields id,title,authors,formats --limit 20

Machine output:

calibredb list --with-library "$CALIBRE_LIBRARY" --fields id,title,authors,tags,formats --for-machine

2) Search and get IDs

calibredb search --with-library "$CALIBRE_LIBRARY" "title:python"

Use IDs in follow-up commands.

3) Show metadata

calibredb show_metadata --with-library "$CALIBRE_LIBRARY" 123

As OPF:

calibredb show_metadata --with-library "$CALIBRE_LIBRARY" --as-opf 123

4) Update metadata fields

calibredb set_metadata --with-library "$CALIBRE_LIBRARY" 123 \
  --field title:"Example Book" \
  --field tags:"python,reference"

5) Add/export books

calibredb add --with-library "$CALIBRE_LIBRARY" "/path/to/book.epub"
calibredb export --with-library "$CALIBRE_LIBRARY" 123 --to-dir "/tmp/export"

6) Library health check

calibredb check_library --with-library "$CALIBRE_LIBRARY"

Content server usage

To target a running Calibre Content server:

calibredb list --with-library "http://hostname:8080/#library_id" --username <user> --password <pass>

From docs: use special #- library id to list server libraries.

Security note: a literal --password <pass> value is passed as a process argument and may be visible to other users on shared machines via process-listing tools. Prefer --password '<stdin>' with the password piped from a password manager, or --password '<f:/path/to/file>' with a 0600 credential file stored outside the repository. Prefer local or trusted hosts for authenticated Content server commands, and redact credentials from shell history, logs, and task transcripts.

Reference files

• Command matrix + options: references/command-matrix.md
• Safe operational playbooks: references/safe-workflows.md